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1.
Nature ; 603(7900): 284-289, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35236981

RESUMO

Homo sapiens was present in northern Asia by around 40,000 years ago, having replaced archaic populations across Eurasia after episodes of earlier population expansions and interbreeding1-4. Cultural adaptations of the last Neanderthals, the Denisovans and the incoming populations of H. sapiens into Asia remain unknown1,5-7. Here we describe Xiamabei, a well-preserved, approximately 40,000-year-old archaeological site in northern China, which includes the earliest known ochre-processing feature in east Asia, a distinctive miniaturized lithic assemblage with bladelet-like tools bearing traces of hafting, and a bone tool. The cultural assembly of traits at Xiamabei is unique for Eastern Asia and does not correspond with those found at other archaeological site assemblages inhabited by archaic populations or those generally associated with the expansion of H. sapiens, such as the Initial Upper Palaeolithic8-10. The record of northern Asia supports a process of technological innovations and cultural diversification emerging in a period of hominin hybridization and admixture2,3,6,11.


Assuntos
Arqueologia , Hominidae , Comportamento de Utilização de Ferramentas , Animais , Osso e Ossos , China , História Antiga , Humanos , Homem de Neandertal
2.
Phys Chem Chem Phys ; 26(16): 12594-12599, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38596870

RESUMO

We report the spin reorientation transition (SRT) and the low field controllable continuous spin switching (SSW) of the Tm0.75Yb0.25FeO3 (TYFO) single crystal in this study. The SRT, characterized by the transition from Γ2(Fx, Cy, Gz)-Γ4(Gx, Ay, Fz), occurs within the temperature range of 20-27 K. Under an external magnetic field of 50 Oe, the SSW occurs along the c-axis at approximately 98 K due to the reversal of Tm3+ magnetic moment induced by the magnetic coupling change between Tm3+ and Fe3+, transitioning from a parallel to an antiparallel alignment. Notably, a continuous SSW is observed along the a-axis at low temperatures, which has not been previously reported in rare earth orthoferrites. This unique behavior can be easily manipulated by low magnetic fields within the temperature range of 2-20 K. Both the spin reorientation transition and spin switching phenomena in the TYFO single crystal arise from interactions between rare earth ions and iron ions and can be effectively regulated by applied low magnetic fields, making it a promising material for low-field spin devices.

3.
Nano Lett ; 22(17): 7151-7157, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-35980177

RESUMO

Flux quantization has been widely regarded as the hallmark of the macroscopic quantum state of superconductivity. However, practical design of superconductor devices exploiting finite size confinement effects may induce exotic phenomena, including nonquantized vortices. In our research, the magnetic flux of vortices has been studied in a series of superconducting strips as a function of the strip width and the penetration depth. In both circumstances, the observation using scanning Hall probe microscope (SHPM) displays a controlled evolution from singly quantized vortices to nonquantized ones. It is also found that the magnetic flux is immune to the flowing supercurrent. The simulations based on Ginzburg-Landau theory agree well with experimental results. The observed behavior of the vortex flux may open new perspectives for fundamental research and applications based on vortex matter, such as vortex-memory devices and magnetic field traps for ultracold atoms.

4.
Protein Expr Purif ; 189: 105988, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34634480

RESUMO

DNA 5-methylcytosine modification plays an important role in the regulation of a variety of biological functions in both prokaryotic and eukaryotic organisms. Previous studies show that DNA Cytosine-5-methylation is predominantly associated with restriction-modification system in bacteria. IPF4390 is deduced to be a putative type II DNA Cytosine-5 methyltransferase from a fresh water cyanobacterium, Microcystis aeruginosa. Both its substrate sequence specificity and catalytic mechanism need to be revealed. In this study, the cloning, expression, purification, DNA binding assays and crystallization of IPF4390 are reported. Results of DNA binding assays demonstrate that IPF4390 can specifically recognize and bind two double-stranded DNAs containing GGNCC (N = A, T, C or G) sequences (HgiBI: 5'-ATAAGGACCAATA-3'; TdeIII: 5'-ATAAGGGCCAATA-3'). Therefore, IPF4390 is probably capable of blocking endonuclease cleavage once restriction sites containing these sequences. Moreover, the crystal of IPF4390 in the presence of TdeIII was obtained, and its X-ray diffraction data were collected and scaled to a maximum resolution of 2.46 Å.


Assuntos
Proteínas de Bactérias/metabolismo , Citosina/metabolismo , DNA (Citosina-5-)-Metiltransferases/metabolismo , DNA Bacteriano/metabolismo , Microcystis/enzimologia , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Clonagem Molecular , Cristalização , Cristalografia por Raios X , DNA (Citosina-5-)-Metiltransferases/química , DNA (Citosina-5-)-Metiltransferases/genética , Metilação de DNA , DNA Bacteriano/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Cinética , Microcystis/química , Plasmídeos/química , Plasmídeos/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
5.
Phys Chem Chem Phys ; 24(2): 735-742, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34935008

RESUMO

The magnetic behavior of a rare-earth orthoferrite ErFeO3 single crystal can be controlled by low magnetic fields from a few to hundreds of Oe. Here we investigated a high-quality ErFeO3 single crystal in the temperature range of 5-120 K, with two types of spin switching in the field-cooled-cooling (FCC) and field-cooled-warming (FCW) processes below the temperature of the spin reorientation (SR) transition from Γ4 to Γ2 at 98-88 K. The magnitude of the applied magnetic fields can regulate two types of spin switching along the a-axis of the ErFeO3 single crystal but does not affect the type and temperature range of the SR transition. An interesting "multi-step" type-II spin switching is observed in FCW under low magnetic fields (H < 18 Oe) just below the SR transition temperature, which is associated with the interaction and the change of magnetic configurations from rare-earth and iron magnetic sublattices. When the magnetic field is lower than 15 Oe, the type-II spin switching in the FCW process gradually changes to a continuous magnetic transition along the a-axis of the ErFeO3 single crystal. As the magnetic field is reduced to less than 17 Oe, the type-I spin switching in the FCW process also transforms into a continuous magnetic transition. Understanding the magnetic reversal effects will help us explore the potential applications of these magnetic materials for future information devices.

6.
J Hum Evol ; 151: 102924, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33418452

RESUMO

The rarity and poor preservation of hominin fossils from the East Asian Early Pleistocene hamper our understanding of their taxonomy and possible phylogenetic relationship with other members of the genus Homo. In the 1970s, four isolated hominin teeth were recovered from the Meipu site, southern China, which biostratigraphic analysis placed in the late Early Pleistocene. Early reports assigned the teeth to late Homo erectus. Since then, the teeth have not been re-evaluated, nor has reliable dating been performed at the Meipu site. Here, biostratigraphic and paleomagnetic dating allow for a more precise chronological constraint of the Meipu hominins in the late Early Pleistocene, between 780 ka and 990 ka, making them one of the few known hominins for this time in mainland Asia. The comparison of the morphology of the Meipu teeth with other members of the genus Homo reveals that the Meipu teeth preserve traits such as moderate shoveling of the I1, the square crown contour of M1, and a buccolingually wider lingual cusp in P4 that make them closer to early Homo specimens from Africa and Homo ergaster from Dmanisi (Georgia). In addition, the Meipu teeth exhibit features that are more typical for late mainland East Asian H. erectus, such as the moderately convex I1 labial surface and a pronouncedly convex I2 labial surface. In these features, the Meipu hominins are morphologically intermediate between African/Dmanisi early Homo and East Asian Middle Pleistocene hominins. This study contributes to a better understanding of the morphologies and the taxonomic status of East Asian Early Pleistocene hominins, a time period for which the hominin evidence with secure stratigraphic context is scarce.


Assuntos
Fósseis/anatomia & histologia , Hominidae/anatomia & histologia , Dente/anatomia & histologia , Animais , China , Microtomografia por Raio-X
7.
Phys Chem Chem Phys ; 21(46): 25826-25837, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31729504

RESUMO

The Z-type hexaferrites Ba3(Zn1-xCox)2Fe24O41 (x = 0.2, 0.4, 0.6, 0.8, defined as Z1-Z4) were synthesized by a sol-gel method. With increasing cobalt concentration, the origin of magnetoelectric (ME) coupling and the effects of crystal parameters, occupation of ions, and magnetocrystalline anisotropy (MCA) on ME current were studied systematically. The mechanism of magnetic phase transition, revealing the evolution of the magnetic order in the temperature range of 10-400 K, was discussed in detail. Our results suggest that the ferroelectricity of Z1-Z4 originates from both inverse Dzyaloshinskii Moriya (DM) interaction and p-d hybridization mechanism. In particular the ME coupling property is only dominated by p-d hybridization with spin-orbit coupling. This study provides an effective way to improve the ME coupling property of hexaferrites, which have potential applications in the design of new electronic devices.

8.
J Hum Evol ; 114: 76-84, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29447762

RESUMO

The dispersal of Neanderthals and their genetic and cultural interactions with anatomically modern humans and other hominin populations in Eurasia are critical issues in human evolution research. Neither Neanderthal fossils nor typical Mousterian assemblages have been reported in East Asia to date. Here we report on artifact assemblages comparable to western Eurasian Middle Paleolithic (Mousterian) at Jinsitai, a cave site in North China. The lithic industry at Jinsitai appeared at least 47-42 ka and persisted until around 40-37 ka. These findings expand the geographic range of the Mousterian-like industries at least 2000 km further to the east than what has been previously recognized. This discovery supplies a missing part of the picture of Middle Paleolithic distribution in Eurasia and also demonstrates the makers' capacity to adapt to diverse geographic regions and habitats of Eurasia.


Assuntos
Arqueologia , Homem de Neandertal , Tecnologia , Animais , Cavernas , China , Humanos
9.
Nano Lett ; 17(8): 5003-5007, 2017 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-28693319

RESUMO

Quantized vortices, as topological defects, play an important role in both physics and technological applications of superconductors. Normally, the nucleation of vortices requires the presence of a high magnetic field or current density, which allow the vortices to enter from the sample boundaries. At the same time, the controllable generation of individual vortices inside a superconductor is still challenging. Here, we report the controllable creation of single quantum vortices and antivortices at any desirable position inside a superconductor. We exploit the local heating effect of a scanning tunneling microscope (STM) tip: superconductivity is locally suppressed by the tip and vortex-antivortex pairs are generated when supercurrent flows around the hot spot. The experimental results are well-explained by theoretical simulations within the Ginzburg-Landau approach.

11.
Glob Chang Biol ; 20(5): 1461-72, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24123607

RESUMO

During the late Miocene, a dramatic global expansion of C4 plant distribution occurred with broad spatial and temporal variations. Although the event is well documented, whether subsequent expansions were caused by a decreased atmospheric CO2 concentration or climate change is a contentious issue. In this study, we used an improved inverse vegetation modeling approach that accounts for the physiological responses of C3 and C4 plants to quantitatively reconstruct the paleoclimate in the Siwalik of Nepal based on pollen and carbon isotope data. We also studied the sensitivity of the C3 and C4 plants to changes in the climate and the atmospheric CO2 concentration. We suggest that the expansion of the C4 plant distribution during the late Miocene may have been primarily triggered by regional aridification and temperature increases. The expansion was unlikely caused by reduced CO2 levels alone. Our findings suggest that this abrupt ecological shift mainly resulted from climate changes related to the decreased elevation of the Himalayan foreland.


Assuntos
Biodiversidade , Dióxido de Carbono/análise , Mudança Climática , Ecossistema , Modelos Biológicos , Plantas , Atmosfera/análise , Carbono/metabolismo , Nepal , Paleontologia , Plantas/metabolismo , Estações do Ano
12.
Hypertens Res ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769134

RESUMO

To investigate the effect of rosuvastatin on gait and balance disorder progression and elucidate the role of cerebrovascular reactivity (CVR) on this effect. From April 2008 to November 2010, 943 hypertensive patients aged ≥60 years were enrolled from the Shandong area of China. Patients were randomized into rosuvastatin and placebo groups. Gait, balance, CVR, fall and stroke were assessed. During an average 72 months of follow-up, the decreasing trends for step length, step speed, and Berg balance scale scores and the increasing trends for step width and chair rising test were slower in the rosuvastatin group when compared to the placebo group. The hazard ratio of incident balance impairment and falls was 0.542 [95% confidence interval (CI) 0.442-0.663] and 0.532 (95% CI 0.408-0.694), respectively, in the rosuvastatin group compared with placebo group. For CVR progression, the cerebrovascular reserve capacity and breath-holding index were increased and the pulsatility index decreased in the rosuvastatin group, while the cerebrovascular reserve capacity and breath-holding index were decreased, and pulsatility index increased in the placebo group. The changes in gait stability and balance function were independently associated with the changes in the CVR. The odds risks of balance impairment and falls were 2.178 (95% CI: 1.491-3.181) and 3.227 (95% CI: 1.634-6.373), respectively, in the patients with CVR impairment and patients without CVR impairment. Rosuvastatin ameliorated gait and balance disorder progression in older patients with hypertension. This effect might result from the improvement in the CVR. This double-blind clinical trial recruited 943 hypertensive patients aged ≥60 years who were randomly administered rosuvastatin and placebo interventions. The data indicates that rosuvastatin significantly ameliorated the progressions of gait and balance disorders in older hypertensive patients. The cerebrovascular reactivity might play an important mediating role in this amelioration.

13.
Sci Adv ; 10(20): eadm7694, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38748795

RESUMO

Past intervals of warming provide the unique opportunity to observe how the East Asia monsoon precipitation response happened in a warming world. However, the available evaluations are primarily limited to the last glacial-to-interglacial warming, which has fundamental differences from the current interglacial warming, particularly in changes in ice volume. Comparative paleoclimate studies of earlier warm interglacial periods can provide more realistic analogs. Here, we present high-resolution quantitative reconstructions of temperature and precipitation from north-central China over the past 800 thousand years. We found that the average precipitation increase, estimated by the interglacial data, was only around one-half of that estimated for the glacial-to-interglacial data, which is attributed to the amplification of climate change by ice volume variations. Analysis of the interglacial data suggests an increase in monsoon precipitation of ~100 mm for a warming level of 2°C on the Chinese Loess Plateau.

14.
Nat Commun ; 15(1): 3611, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38684677

RESUMO

The emergence of Homo sapiens in Eastern Asia is a topic of significant research interest. However, well-preserved human fossils in secure, dateable contexts in this region are extremely rare, and often the subject of intense debate owing to stratigraphic and geochronological problems. Tongtianyan cave, in Liujiang District of Liuzhou City, southern China is one of the most important fossils finds of H. sapiens, though its age has been debated, with chronometric dates ranging from the late Middle Pleistocene to the early Late Pleistocene. Here we provide new age estimates and revised provenience information for the Liujiang human fossils, which represent one of the most complete fossil skeletons of H. sapiens in China. U-series dating on the human fossils and radiocarbon and optically stimulated luminescence dating on the fossil-bearing sediments provided ages ranging from ~33,000 to 23,000 years ago (ka). The revised age estimates correspond with the dates of other human fossils in northern China, at Tianyuan Cave (~40.8-38.1 ka) and Zhoukoudian Upper Cave (39.0-36.3 ka), indicating the geographically widespread presence of H. sapiens across Eastern Asia in the Late Pleistocene, which is significant for better understanding human dispersals and adaptations in the region.


Assuntos
Fósseis , Datação Radiométrica , Humanos , China , Cavernas , Esqueleto , História Antiga , Sedimentos Geológicos
15.
Front Immunol ; 14: 1324516, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38250078

RESUMO

RNF5 is an E3 ubiquitin ligase involved in various physiological processes such as protein localization and cancer progression. Recent studies have shown that RNF5 significantly inhibits antiviral innate immunity by promoting the ubiquitination and degradation of STING and MAVS, which are essential adaptor proteins, as well as their downstream signal IRF3. The abundance of RNF5 is delicately regulated by both host factors and viruses. Host factors have been found to restrict RNF5-mediated ubiquitination, maintaining the stability of STING or MAVS through distinct mechanisms. Meanwhile, viruses have developed ingenious strategies to hijack RNF5 to ubiquitinate and degrade immune proteins. Moreover, recent studies have revealed the multifaceted roles of RNF5 in the life cycle of various viruses, including SARS-CoV-2 and KSHV. Based on these emerging discoveries, RNF5 represents a novel means of modulating antiviral immunity. In this review, we summarize the latest research on the roles of RNF5 in antiviral immunity and virus life cycle. This comprehensive understanding could offer valuable insights into exploring potential therapeutic applications focused on targeting RNF5 during viral infections.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Imunidade Inata , Ubiquitina-Proteína Ligases , Viroses , Transporte Proteico , Viroses/imunologia , Ubiquitina-Proteína Ligases/imunologia
16.
ACS Nano ; 16(12): 21208-21215, 2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36453842

RESUMO

The precise organization and orientation of anisotropic nanoparticles (NPs) on substrates over a large area is key to the application of NP assemblies in functional optical, electronic, and magnetic devices, but achieving such high-precision NP assembly still remains challenging. Here, we demonstrate the site-selective assembly of magnetic nanoellipsoids into large-area precisely positioned, orientationally controlled arrays via a combination of chemical patterning and magnetic manipulation. Magnetic ellipsoidal NPs are selectively positioned on predetermined chemical patterns with high fidelity through electrostatic interactions and aligned uniformly in line with an applied magnetic field. The position, orientation, and interparticle spacing of the ellipsoids can be precisely tuned by controlling the chemical patterns and magnetic field. This approach is simple to implement and can generate centimeter-scale arrays in high yield (up to 99%). The arrays exhibit collective magnetic responses that are dependent on the orientation of the ellipsoids. This work offers a tool for the fabrication of precisely engineered arrays of anisotropic NPs for applications such as metasurface and artificial spin ice.

17.
Biosensors (Basel) ; 11(10)2021 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-34677355

RESUMO

In this study, we designed and manufactured a series of different microstructure topographical cues for inducing neuronal differentiation of cells in vitro, with different topography, sizes, and structural complexities. We cultured PC12 cells in these microstructure cues and then induced neural differentiation using nerve growth factor (NGF). The pheochromocytoma cell line PC12 is a validated neuronal cell model that is widely used to study neuronal differentiation. Relevant markers of neural differentiation and cytoskeletal F-actin were characterized. Cellular immunofluorescence detection and axon length analysis showed that the differentiation of PC12 cells was significantly different under different isotropic and anisotropic topographic cues. The expression differences of the growth cone marker growth-associated protein 43 (GAP-43) and sympathetic nerve marker tyrosine hydroxylase (TH) genes were also studied in different topographic cues. Our results revealed that the physical environment has an important influence on the differentiation of neuronal cells, and 3D constraints could be used to guide axon extension. In addition, the neurotoxin 6-hydroxydopamine (6-OHDA) was used to detect the differentiation and injury of PC12 cells under different topographic cues. Finally, we discussed the feasibility of combining the topographic cues and the microfluidic chip for neural differentiation research.


Assuntos
Diferenciação Celular , Sinais (Psicologia) , Neurônios , Animais , Células PC12 , Ratos
18.
Innovation (Camb) ; 2(3): 100130, 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34557770

RESUMO

It has recently become clear that several human lineages coexisted with Homo sapiens during the late Middle and Late Pleistocene. Here, we report an archaic human fossil that throws new light on debates concerning the diversification of the Homo genus and the origin of H. sapiens. The fossil was recovered in Harbin city in northeastern China, with a minimum uranium-series age of 146 ka. This cranium is one of the best preserved Middle Pleistocene human fossils. Its massive size, with a large cranial capacity (∼1,420 mL) falling in the range of modern humans, is combined with a mosaic of primitive and derived characters. It differs from all the other named Homo species by presenting a combination of features, such as long and low cranial vault, a wide and low face, large and almost square orbits, gently curved but massively developed supraorbital torus, flat and low cheekbones with a shallow canine fossa, and a shallow palate with thick alveolar bone supporting very large molars. The excellent preservation of the Harbin cranium advances our understanding of several less-complete late Middle Pleistocene fossils from China, which have been interpreted as local evolutionary intermediates between the earlier species Homo erectus and later H. sapiens. Phylogenetic analyses based on parsimony criteria and Bayesian tip-dating suggest that the Harbin cranium and some other Middle Pleistocene human fossils from China, such as those from Dali and Xiahe, form a third East Asian lineage, which is a part of the sister group of the H. sapiens lineage. Our analyses of such morphologically distinctive archaic human lineages from Asia, Europe, and Africa suggest that the diversification of the Homo genus may have had a much deeper timescale than previously presumed. Sympatric isolation of small populations combined with stochastic long-distance dispersals is the best fitting biogeographical model for interpreting the evolution of the Homo genus.

19.
Innovation (Camb) ; 2(3): 100131, 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34557771

RESUMO

As one of the most complete archaic human fossils, the Harbin cranium provides critical evidence for studying the diversification of the Homo genus and the origin of Homo sapiens. However, the unsystematic recovery of this cranium and a long and confused history since the discovery impede its accurate dating. Here, we carried out a series of geochemical analyses, including non-destructive X-ray fluorescence (XRF), rare earth elements (REE), and the Sr isotopes, to test the reported provenance of the Harbin cranium and get better stratigraphic constraints. The results show that the Harbin cranium has very similar XRF element distribution patterns, REE concentration patterns, and Sr isotopic compositions to those of the Middle Pleistocene-Holocene mammalian and human fossils recently recovered from the Harbin area. The sediments adhered in the nasal cavity of the Harbin cranium have a 87Sr/86Sr ratio of 0.711898, falling in the variation range measured in a core drilled near the Dongjiang Bridge, where the cranium was discovered during its reconstruction. The regional stratigraphic correlations indicate that the Harbin cranium was probably from the upper part of the Upper Huangshan Formation of the Harbin area, which has an optically stimulated luminescence dating constraint between 138 and 309 ka. U-series disequilibrium dating (n = 10) directly on the cranium suggests that the cranium is older than 146 ka. The multiple lines of evidence from our experiments consistently support the theory that the Harbin cranium is from the late Middle Pleistocene of the Harbin area. Our study also shows that geochemical approaches can provide reliable evidence for locating and dating unsystematically recovered human fossils, and potentially can be applied to other human fossils without clear provenance and stratigraphy records.

20.
ACS Appl Mater Interfaces ; 13(35): 42138-42145, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34432434

RESUMO

By preparing a series of high-quality Fe1.1Se0.8Te0.2 films on the CaF2 substrate via pulsed laser deposition, we reveal the evolution of the structure as well as the superconductivity with the film thickness. We have found that there exists a threshold thickness above which the critical temperature Tc reaches its optimal value of 23.18 K with large activation energy, promising for high-field technological applications. Most importantly, the thick films have been found in a metastable state due to the fragile balance between the increased strain energy and the large compressive stress. Once the balance is broken by an external perturbation, a unique structure avalanche happens with a large part of the film exfoliated from the substrate and curves out. The exfoliated part of the film remains a single phase, with its lattice parameter and Tc recovering the bulk values. Our results clearly demonstrate the close relation between the compressive stress of the film/substrate interface and the high critical temperature observed in FeSeTe films. Moreover, this also provides an efficient way to fabricate free-standing single-phase FeSeTe crystals in the phase-separation regime.

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