High-Performance WS2 MOSFETs with Bilayer WS2 Contacts.

WS2 is a promising transition-metal dichalcogenide (TMDC) for use as a channel material in extreme-scaled metal-oxide-semiconductor field-effect transistors (MOSFETs) due to its monolayer thickness, high carrier mobility, and its potential for symmetric n-type and p-type MOSFET performance. However, the formation of stable, low-barrier-height contacts to monolayer TMDCs continues to be a challenge. This study introduces an innovative approach to realize high-performance WS2 MOSFETs by utilizing bilayer WS2 (2L-WS2) in the contact region grown through a two-step chemical vapor deposition process. The 2L-WS2 devices demonstrate a high I ON/I OFF ratio of 108 and a saturated drain current, I D(SAT), of 280 µA/µm (386 µA/µm) at room temperature (78 K), even while still using conventional metal (Pd or Ni) contacts. Devices featuring a 1L-WS2 channel and 2L-WS2 in the contact regions were also fabricated, and they exhibited performance comparable to that of 2L-WS2 devices. The devices also exhibit good stability with nearly identical performance after storage over a 13 month period. The study highlights the benefits of a hybrid channel thickness approach for TMDC transistors.

Correction to Nb Doping and Alloying of 2D WS2 by Atomic Layer Deposition for 2D Transition Metal Dichalcogenide Transistors and HER Electrocatalysts.

[This corrects the article DOI: 10.1021/acsanm.4c00094.].

Comparison of systematic and combined biopsy for the detection of prostate cancer.

ABSTRACT: Systematic prostate biopsy has limitations, such as overdiagnosis of clinically insignificant prostate cancer and underdiagnosis of clinically significant prostate cancer. Magnetic resonance imaging (MRI)-guided biopsy, a promising alternative, might improve diagnostic accuracy. To compare the cancer detection rates of systematic biopsy and combined biopsy (systematic biopsy plus MRI-targeted biopsy) in Asian men, we conducted a retrospective cohort study of men who underwent either systematic biopsy or combined biopsy at two medical centers (Queen Mary Hospital and Tung Wah Hospital, Hong Kong, China) from July 2015 to December 2022. Descriptive statistics were calculated, and univariate and multivariate logistic regression analyses were performed. The primary and secondary outcomes were prostate cancer and clinically significant prostate cancer. A total of 1391 participants were enrolled. The overall prostate cancer detection rates did not significantly differ between the two groups (36.3% vs 36.6%, odds ratio [OR] = 1.01, 95% confidence interval [CI]: 0.81-1.26, P = 0.92). However, combined biopsy showed a significant advantage in detecting clinically significant prostate cancer (Gleason score ≥ 3+4) in patients with a total serum prostate-specific antigen (tPSA) concentration of 2-10 ng ml -1 (systematic vs combined: 11.9% vs 17.5%, OR = 1.58, 95% CI: 1.08-2.31, P = 0.02). Specifically, in the transperineal biopsy subgroup, combined biopsy significantly outperformed systematic biopsy in the detection of clinically significant prostate cancer (systematic vs combined: 12.6% vs 24.0%, OR = 2.19, 95% CI: 1.21-3.97, P = 0.01). These findings suggest that in patients with a tPSA concentration of 2-10 ng ml -1 , MRI-targeted biopsy may be of greater predictive value than systematic biopsy in the detection of clinically significant prostate cancer.

FoxO3 Regulates Mouse Bone Mesenchymal Stem Cell Fate and Bone-Fat Balance During Skeletal Aging.

Age-related osteoporosis is characterized by an imbalance between osteogenic and adipogenic differentiation in bone mesenchymal stem cells (BMSCs). Forkhead box O 3 (FoxO3) transcription factor is involved in lifespan and cell differentiation. In this study, we explore whether FoxO3 regulates age-related bone loss and marrow fat accumulation. The expression levels of FoxO3 in BMSCs during aging were detected in vivo and in vitro. To explore the role of FoxO3 in osteogenic and adipogenic differentiation, primary BMSCs were isolated from young and aged mice. FoxO3 expression was modulated by adenoviral vector transfection. The role of FoxO3 in bone-fat balance was evaluated by alizarin red S staining, oil red O staining, quantitative reverse transcription-polymerase chain reaction, Western blot, and histological analysis. Age-related bone loss and fat deposit are associated with downregulation of FoxO3. Overexpression of FoxO3 alleviated age-related bone loss and marrow fat accumulation in aged mice. Mechanistically, FoxO3 reduced adipogenesis and enhanced osteogenesis of BMSCs via downregulation of PPAR-γ and Notch signaling, respectively. In conclusion, FoxO3 is an essential factor controlling the fate of BMSCs and is a potential target for the prevention of age-related osteoporosis.

Nb Doping and Alloying of 2D WS2 by Atomic Layer Deposition for 2D Transition Metal Dichalcogenide Transistors and HER Electrocatalysts.

We utilize plasma-enhanced atomic layer deposition to synthesize two-dimensional Nb-doped WS2 and NbxW1-xSy alloys to expand the range of properties and improve the performance of 2D transition metal dichalcogenides for electronics and catalysis. Using a supercycle deposition process, films are prepared with compositions spanning the range from WS2 to NbS3. While the W-rich films form crystalline disulfides, the Nb-rich films form amorphous trisulfides. Through tuning the composition of the films, the electrical resistivity is reduced by 4 orders of magnitude compared to pure ALD-grown WS2. To produce Nb-doped WS2 films, we developed a separate ABC-type supercycle process in which a W precursor pulse precedes the Nb precursor pulse, thereby reducing the minimum Nb content of the film by a factor of 3 while maintaining a uniform distribution of the Nb dopant. Initial results are presented on the electrical and electrocatalytic performances of the films. Promisingly, the NbxW1-xSy films of 10 nm thickness and composition x ≈ 0.08 are p-type semiconductors and have a low contact resistivity of (8 ± 1) × 102 Ω cm to Pd/Au contacts, demonstrating their potential use in contact engineering of 2D TMD transistors.

Is La3Ni2O6.5 a Bulk Superconducting Nickelate?

Superconducting states onsetting at moderately high temperatures have been observed in epitaxially stabilized RENiO2-based thin films. However, recently, it has also been reported that superconductivity at high temperatures is observed in bulk La3Ni2O7-δ at high pressure, opening further possibilities for study. Here we report the reduction profile of La3Ni2O7 in a stream of 5% H2/Ar gas and the isolation of the metastable intermediate phase La3Ni2O6.45, which is based on Ni2+. Although this reduced phase does not superconduct at ambient or high pressures, it offers insights into the Ni-327 system and encourages future study of nickelates as a function of oxygen content.

Stuffed Rare-Earth Garnets.

We report the synthesis and magnetic characterization of stuffed rare-earth gallium garnets, RE3+xGa5-xO12 (RE = Lu, Yb, Er, Dy, Gd), for x up to 0.5. The excess rare-earth ions partly fill the octahedral sites normally fully occupied by Ga3+, forming disordered pairs of corner-shared face-sharing magnetic tetrahedra. The Curie-Weiss constants and observed effective moments per rare-earth are smaller than are seen for the unstuffed gallium garnets. No significant change in the field-dependent magnetization is observed but missing entropy is seen when integrating the heat capacity down to 0.5 K.

Erbium-Excess Gallium Garnets.

A series of garnets of formula Er3+xGa5-xO12 are described, for which we report the crystal structures for both polycrystalline and single-crystal samples. The x limit in the garnet phase is between 0.5 and 0.6 under our conditions, with the Er fully occupying the dodecahedral (24c) garnet site plus some of the octahedral site (16a) in place of the Ga normally present. Long-range antiferromagnetic order with spin-ice-like frustration is suggested by the transition temperature (TN ≈ 0.8 K) being lower than the Curie-Weiss theta. The magnetic ordering temperature does not depend on the Er excess, but there is increasing residual entropy as the Er excess is increased, highlighting the potential for unusual magnetic behavior in this system. The field-dependent magnetic entropy trend is consistent with the reported behavior for frustrated triangular magnetic systems: an increasing transition temperature with a broader hump as the applied field increases [Xing, J.; Phys. Rev. Mater. 2019, 3(11), 114413;Filippi, J.; Solid State Commun. 1977, 23(9), 613-616; Bloxsom, J. A. Thermal and Magnetic Studies of Spin Ice Compounds. University College London, 2016].

Electron doping of a double-perovskite flat-band system.

Electronic structure calculations indicate that the Sr2FeSbO6 double perovskite has a flat-band set just above the Fermi level that includes contributions from ordinary subbands with weak kinetic electron hopping plus a flat subband that can be attributed to the lattice geometry and orbital interference. To place the Fermi energy in that flat band, electron-doped samples with formulas Sr2-xLaxFeSbO6 (0 ≤ x ≤ 0.3) were synthesized, and their magnetism and ambient temperature crystal structures were determined by high-resolution synchrotron X-ray powder diffraction. All materials appear to display an antiferromagnetic-like maximum in the magnetic susceptibility, but the dominant spin coupling evolves from antiferromagnetic to ferromagnetic on electron doping. Which of the three subbands or combinations is responsible for the behavior has not been determined.

LncRNA SNHG1 promotes renal cell carcinoma progression through regulation of HMGA2 via sponging miR-103a.

BACKGROUND: Long noncoding RNAs (LncRNAs) plays a vital role in tumorigenesis and development. The molecular mechanism of SNHG1 in renal cell carcinoma (RCC) has not been illustrated. The aim of this research was to explore the expression and function of LncRNA SNHG1 in RCC. MATERIAL AND METHODS: The expression of SNHG1 in clinical tissues and RCC cell lines was detected. Luciferase reporter assay was performed to verify the correlation between SNHG1, miR-103a, and HMGA2. CCK-8 assay was performed to examine cell viability. Cell apoptosis was analyzed using flow cytometry. Cell invasion capacity was determined by Transwell assays. The protein level of HMGA2 was analyzed by Western blotting. RESULTS: The expression of SNHG1 markedly increased in RCC tissues and cell lines. Subsequent studies identified SNHG1 as a miRNA sponge for miR-103a. In addition, SNHG1 knockdown and miR-103a overexpression significantly inhibited progression of RCC. miR-103a also regulated HMGA2 levels. CONCLUSION: Our findings showed that SNHG1 was upregulated in RCC cells and tissues. SNHG1 promoted the malignant characteristics of RCC cells. Its regulatory effect may be regulation of HMGA2 by sponging miR-103a. Therefore, Our study facilitates the understanding of SNHG1 function in RCC.

Ferromagnetic Double Perovskite Semiconductors with Tunable Properties.

The authors successfully dope the magnetically silent double perovskite semiconductor Sr2 GaSbO6  to induce ferromagnetism and tune its bandgap, with Ga3+ partially substituted by the magnetic trivalent cation Mn3+ , in a rigid cation ordering with Sb5+ . The new ferromagnetic semiconducting Sr2 Ga1- x Mnx SbO6  double perovskite, which crystallizes in tetragonal symmetry (space group I4/m) and has tunable ferromagnetic ordering temperature and bandgap, suggests that magnetic ion doping of double perovskites is a productive avenue toward obtaining materials for application in next-generation oxide-based spintronic devices.

Hole and Electron Doping of Topochemically Reduced Ni(I)/Ru(II) Insulating Ferromagnetic Oxides.

LaxSr2-xNiRuO6, LaxSr4-xNiRuO8, and LaxSr3-xNiRuO7 are, respectively, the n = ∞, 1, and 2 members of the (Lax/2Sr1-(x/2))nSr(Ni0.5Ru0.5)nO3n+1 compositional series. Reaction with CaH2, in the case of the LaxSr2-xNiRuO6 perovskite phases, or Zr oxygen getters in the case of the LaxSr4-xNiRuO8 and LaxSr3-xNiRuO7 Ruddlesden-Popper phases, yields the corresponding topochemically reduced (Lax/2Sr1-(x/2))nSr(Ni0.5Ru0.5)nO3n-1 compounds (LaxSr2-xNiRuO4, LaxSr4-xNiRuO6, and LaxSr3-xNiRuO5), which contain Ni and Ru cations in square-planar coordination sites. The x = 1 members of each series (LaSrNiRuO4, LaSr3NiRuO6, and LaSr2NiRuO5) exhibit insulating ferromagnetic behavior at low temperature, attributable to exchange couplings between the Ni1+ and Ru2+ centers they contain. Increasing the La3+ concentration (x > 1) leads to a reduction of some of the Ru2+ centers to Ru1+ centers and a suppression of the ferromagnetic state (lower Tc, reduced saturated ferromagnet moment). In contrast, increasing the Sr2+ concentration (x < 1) oxidizes some of the Ru2+ centers to Ru3+ centers and enhances the ferromagnetic coupling (increased Tc, increased saturated ferromagnet moment) for the n = ∞ and n = 2 samples but appears to have no influence on the magnetic ordering temperature of the n = 1 samples. The magnetic couplings and influence of doping are discussed on the basis of superexchange and direct exchange couplings between the square-planar Ni and Ru centers.

[Advances on treatment of periprosthetic infection and antibiotic delivery system after total hip arthroplasty].

Periprosthetic infection after hip replacement is a clinical catastrophic disease, which often leads to the failure of the prosthesis. It needs the combination of systemic antibiotics to cure the infection, which brings huge burden to doctors and patients. There are strict indications for debridement and one-stage revision of the prosthesis, and few cases meet the requirements. The second revision is still the gold standard for the treatment of periprosthetic infection. It is suitable for all infection conditions and has a high success rate. On the second phase of renovation, the antibiotic sustained release system plays a key role, and the carrier of antibiotic sustained-release system is the focus of current research, including classic bone cement and absorbable biomaterials. Bone cement has strong mechanical strength, but the antibiotic release shows a sharp decline trend; the absorbable biomaterials can continuously release antibiotics with high concentration, but the mechanical strength is poor, so it could not use alone. The combination of bone cement and absorbable biomaterials will be an ideal antibiotic carrier. PMMA is the most commonly used antibiotic carrier, but the antibiotic release concentration is decreased sharply after 24 hours. It will be difficult to control the infection and increase the risk of bacterial resistance if it is lower than the minimum inhibitory concentration. The biodegradable materials can release antibiotics completely, with long release time and high concentration, but low mechanical strength. Antibiotic spacer plays an important role in the control of infection. In the future, how to further extend the antibiotic release time of antibiotic sustained-release system, increase the amount of antibiotic release and maintain the mechanical strength of the material will be studied.

Evidence of Paracrystalline Cation Order in the Ruddlesden-Popper Phase LaSr3NiRuO8 through Neutron Total Scattering Techniques.

Cation ordering in perovskite-derived phases can lead to a wealth of tunable physical properties. Ordering is typically driven by a large difference between the cation size and charge, but many Ruddlesden-Popper phases An+1BnO3n+1 appear to lack such B-site ordering, even when these differences are present. One such example is the "double" Ruddlesden-Popper n = 1 composition LaSr3NiRuO8. In this material, a lack of B-site ordering is observed through traditional crystallographic techniques, but antiferromagnetic ordering in the magnetism data suggests that B-site cation ordering is indeed present. Neutron total scattering, particularly analysis of the neutron pair distribution function, reveals that the structure is locally B-site-ordered below 6 Å but becomes slightly disordered in the midrange structure around 12 Å. This provides evidence for paracrystalline order in this material: cation ordering within a single perovskite sheet that lacks perfect registry within the three-dimensional stack of sheets. This work highlights the importance of employing a structural technique that can probe both the local and midrange order in addition to the crystallographic structure and provides a structural origin to the observed magnetic properties of LaSr3NiRuO8. Further, it is proposed that paracrystalline order is likely to be common among these layered-type oxides.

Hole and Electron Doping of the 4d Transition-Metal Oxyhydride LaSr3 NiRuO4 H4.

Hole or electron doping of phases prepared by topochemical reactions (e.g. anion deintercalation or anion-exchange) is extremely challenging as these low-temperature conversion reactions are typically very sensitive to the electron counts of precursor phases. Herein we report the successful hole and electron doping of the transition-metal oxyhydride LaSr3 NiRuO4 H4 by first preparing precursors in the range Lax Sr4-x NiRuO8 0.5

Advances on treatment of periprosthetic infection and antibiotic delivery system after total hip arthroplasty / 中国骨伤

Periprosthetic infection after hip replacement is a clinical catastrophic disease, which often leads to the failure of the prosthesis. It needs the combination of systemic antibiotics to cure the infection, which brings huge burden to doctors and patients. There are strict indications for debridement and one-stage revision of the prosthesis, and few cases meet the requirements. The second revision is still the gold standard for the treatment of periprosthetic infection. It is suitable for all infection conditions and has a high success rate. On the second phase of renovation, the antibiotic sustained release system plays a key role, and the carrier of antibiotic sustained-release system is the focus of current research, including classic bone cement and absorbable biomaterials. Bone cement has strong mechanical strength, but the antibiotic release shows a sharp decline trend; the absorbable biomaterials can continuously release antibiotics with high concentration, but the mechanical strength is poor, so it could not use alone. The combination of bone cement and absorbable biomaterials will be an ideal antibiotic carrier. PMMA is the most commonly used antibiotic carrier, but the antibiotic release concentration is decreased sharply after 24 hours. It will be difficult to control the infection and increase the risk of bacterial resistance if it is lower than the minimum inhibitory concentration. The biodegradable materials can release antibiotics completely, with long release time and high concentration, but low mechanical strength. Antibiotic spacer plays an important role in the control of infection. In the future, how to further extend the antibiotic release time of antibiotic sustained-release system, increase the amount of antibiotic release and maintain the mechanical strength of the material will be studied.

Exsolution of SrO during the Topochemical Conversion of LaSr3CoRuO8 to the Oxyhydride LaSr3CoRuO4H4.

 Reaction of the n = 1 Ruddlesden-Popper oxide LaSr3CoRuO8 with CaH2 yields the oxyhydride phase LaSr3CoRuO4H4 via a topochemical anion exchange. Close inspection of the X-ray and neutron powder diffraction data in combination with HAADF-STEM images reveals that the nanoparticles of SrO are exsolved from the system during the reaction, with the change in cation stoichiometry accommodated by the inclusion of n > 1 (Co/Ru)nOn+1H2n "perovskite" layers into the Ruddlesden-Popper stacking sequence. This novel pseudotopochemical process offers a new route for the formation of n > 1 Ruddlesden-Popper structured materials. Magnetization data are consistent with a LaSr3Co+Ru2+O4H4 (Co+, d8, S = 1; Ru2+, d6, S = 0) oxidation/spin state combination. Neutron diffraction and µ+SR data show no evidence for long-range magnetic order down to 2 K, suggesting the diamagnetic Ru2+ centers impede the Co-Co magnetic-exchange interactions.

MoTe2 Lateral Homojunction Field-Effect Transistors Fabricated using Flux-Controlled Phase Engineering.

The coexistence of metallic and semiconducting polymorphs in transition-metal dichalcogenides (TMDCs) can be utilized to solve the large contact resistance issue in TMDC-based field effect transistors (FETs). A semiconducting hexagonal (2H) molybdenum ditelluride (MoTe2) phase, metallic monoclinic (1T') MoTe2 phase, and their lateral homojunctions can be selectively synthesized in situ by chemical vapor deposition due to the small free energy difference between the two phases. Here, we have investigated, in detail, the structural and electrical properties of in situ-grown lateral 2H/1T' MoTe2 homojunctions grown using flux-controlled phase engineering. Using atomic-resolution plan-view and cross-sectional transmission electron microscopy analyses, we show that the round regions of near-single-crystalline 2H-MoTe2 grow out of a polycrystalline 1T'-MoTe2 matrix. We further demonstrate the operation of MoTe2 FETs made on these in situ-grown lateral homojunctions with 1T' contacts. The use of a 1T' phase as electrodes in MoTe2 FETs effectively improves the device performance by substantially decreasing the contact resistance. The contact resistance of 1T' electrodes extracted from transfer length method measurements is 470 ± 30 Ω·µm. Temperature- and gate-voltage-dependent transport characteristics reveal a flat-band barrier height of ∼30 ± 10 meV at the lateral 2H/1T' interface that is several times smaller and shows a stronger gate modulation, compared to the metal/2H Schottky barrier height. The information learned from this analysis will be critical to understanding the properties of MoTe2 homojunction FETs for use in memory and logic circuity applications.

Rhodium-containing oxide-hydrides: covalently stabilized mixed-anion solids.

The first rhodium-containing oxide-hydride phases, LaSrCo0.5Rh0.5O3H and La0.5Sr1.5Mn0.5Rh0.5O3H, have been prepared via topochemical anion exchange. This clearly demonstrates the ability of rhodium, a late 4d transition metal, to kinetically stabilize oxide-hydride lattices, reinforcing the paradigm of covalent stabilization of transition-metal oxide-hydride phases.