Engineering the electronic band structure of material systems enables the unprecedented exploration of new physical properties that are absent in natural or as-synthetic materials. Half metallicity, ...an intriguing physical property arising from the metallic nature of electrons with singular spin polarization and insulating for oppositely polarized electrons, holds a great potential for a 100% spin-polarized current for high-efficiency spintronics. Conventionally synthesized thin films hardly sustain half metallicity inherited from their 3D counterparts. A fundamental challenge, in systems of reduced dimensions, is the almost inevitable spin-mixed edge or surface states in proximity to the Fermi level. Here, we predict electric field-induced half metallicity in bilayer A-type antiferromagnetic van der Waals crystals (i.e., intralayer ferromagnetism and interlayer antiferromagnetism), by employing density functional theory calculations on vanadium diselenide. Electric fields lift energy levels of the constituent layers in opposite directions, leading to the gradual closure of the gap of singular spin-polarized states and the opening of the gap of the others. We show that a vertical electrical field is a generic and effective way to achieve half metallicity in A-type antiferromagnetic bilayers and realize the spin field effect transistor. The electric field-induced half metallicity represents an appealing route to realize 2D half metals and opens opportunities for nanoscale highly efficient antiferromagnetic spintronics for information processing and storage.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
2D polarization materials have emerged as promising candidates for meeting the demands of device miniaturization, attributed to their unique electronic configurations and transport characteristics. ...Although the existing inherent and sliding mechanisms are increasingly investigated in recent years, strategies for inducing 2D polarization with innovative mechanisms remain rare. This study introduces a novel 2D Janus state by modulating the puckered structure. Combining scanning probe microscopy, transmission electron microscopy, and density functional theory calculations, this work realizes force‐triggered out‐of‐plane and in‐plane dipoles with distorted smaller warping in GeSe. The Janus state is preserved after removing the external mechanical perturbation, which could be switched by modulating the sliding direction. This work offers a versatile method to break the space inversion symmetry in a 2D system to trigger polarization in the atomic scale, which may open an innovative insight into configuring novel 2D polarization materials.
2D polarization materials are promising for miniaturized devices due to their unique properties. However, strategies for creating 2D polarization through new mechanisms are rare. This work introduces a 2D Janus structure with both vertical and planar polarization, achieved by applying force with a nanoprobe. This technique breaks symmetry at the atomic level, inducing polarization and paving the way for new 2D polarization materials' development and design.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Percutaneous vertebroplasty (PVP) is now well accepted in the treatment of painful osteopathic vertebral compression fractures (OVCF), providing early pain relief and strengthening of the bone of the ...vertebrae. However, some patients still experienced severe back pain after PVP.
To analyze the possible reason for unsatisfactory back pain relief (UBPR) after PVP at early stage.
Retrospective analysis.
Hong-Hui Hospital in Xi'an.
Between March 2013 and January 2015, a total of 1,316 patients with OVCF were treated by PVP at our Hospital. Demographics, clinical data, and surgical data were collected to analyze the factors associated with UBPR after PVP.
Sixty cases complained of UBPR, and the prevalence was 4.6%. Univariate analyses showed that preoperative bone mineral density (BMD), number of fractures, cement distribution and volume injected per level, lumbodorsal fascia contusion, and depression were associated with UBPR after PVP (P < 0.001). Multivariate analysis revealed that preoperative BMD (odds ratio OR, 3.577; P = 0.029), lumbodorsal fascia contusion (OR, 3.805; P = 0.002), number of fractures (OR, 3.440; P < 0.001), cement volume injected per level (OR, 0.079; P < 0.001), cement distribution (OR, 3.009; P = 0.013), and depression (OR, 3.426; P = 0.028) were independently associated with UBPR after PVP at the early postoperative stage.
A further prospective controlled study is needed to explore the association between the different degrees of the aforementioned factors and UBPR after PVP.
Preoperative low BMD, lumbodorsal fascial injury, multiple segment PVP, insufficient cement injected volume, unsatisfactory cement distribution, and depression were strong risk factors associated with UBPR after PVP in patients with OVCF.
Unsatisfactory back pain relief, residual back pain, percutaneous vertebroplasty.
Combination therapy with pegylated interferon (PEG‐IFN) and nucleos(t)ide analogues (NAs) can enhance hepatitis B surface antigen (HBsAg) clearance. However, the specific treatment strategy and the ...patients who would benefit the most are unclear. Therefore, we assessed the HBsAg loss rate of add‐on PEG‐IFN and explored the factors associated with HBsAg loss in chronic hepatitis B (CHB) patients. This was a real‐world cohort study of adults with CHB. Hepatitis B e antigen (HBeAg)‐negative NAs‐treated patients with baseline HBsAg ≤1500 IU/ml and HBV DNA < the lower limit of detection, or 100 IU/ml, received 48 weeks of add‐on PEG‐IFN. The primary outcome of the study was the rate of HBsAg loss at 48 weeks of combination treatment. Using multivariable logistic regression analysis, we determined factors associated with HBsAg loss. HBsAg loss in 2579 patients (mean age: 41.2 years; 80.9% male) was 36.7% (947 patients) at 48 weeks. HBsAg loss was highest in patients from south‐central and southwestern China (40.0%). Factors independently associated with HBsAg loss included: increasing age (odds ratio = 0.961); being male (0.543); baseline HBsAg level (0.216); HBsAg decrease at 12 weeks (between 0.5 and 1.0 log10 IU/ml 2.405 and >1.0 log10 IU/ml 7.370); alanine aminotransferase (ALT) increase at 12 weeks (1.365); haemoglobin (HGB) decrease at 12 weeks (1.558). There was no difference in the primary outcomes associated with the combination regimen. In conclusion, HBsAg loss by combination therapy was higher in patients from southern China than those from the north. An increased chance of HBsAg loss was associated with baseline characteristics and dynamic changes in clinical indicators.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
Photodetectors based on reduced graphene oxide (rGO) have attracted much attention owing to their simple and low‐cost fabrication process. However, the aggregation and defects of rGO flakes still ...limit the performance of rGO photodetectors. Controlling the composition of rGO has become a vital factor for its prospective applications. For example, the interconnection between rGO and polymers for modified morphologies of rGO films leads to an enhanced performance of devices. In this work, a practical approach to engineer surface uniformity and enhance the performance of a photodetector by modifying the rGO film with hydrophilic polymers poly(vinyl alcohol) (PVA) is reported. Compared with the rGO photodetector, the on/off ratio for the PVA/rGO photodetector shows 3.5 times improvement, and the detectivity shows 53% enhancement even when the photodetector is operated at a low bias of 0.3 V. This study provides an effective route to realize PVA/rGO photodetectors with a low‐power operation which shows promising opportunities for the future development of green systems.
A practical approach to enhance the performance of a reduced graphene oxide (rGO) photodetector by modifying the rGO film with poly(vinyl alcohol) (PVA) is reported. Compared with the rGO photodetector, the on/off ratio for the PVA/rGO photodetector shows 3.5 times improvement, and the detectivity shows 53% enhancement at a low operating bias of 0.3 V.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
In this paper, the facile synthesis of hybrid Fe3O4 magnetic nanoparticles carrying helical poly(phenyl isocyanide) (PPI) arms via both “grafting from” and “grafting onto” strategies is reported. ...First, alkyne‐Pd(II) catalysts are anchored onto the surface of the Fe3O4 magnetic nanoparticle, which promote the polymerization of enantiopure phenyl isocyanide, affording the expected hybrid magnetic nanoparticle with Fe3O4 in core and helical PPI as arms. The nanoparticle also exhibits highly optical activity due to the excess of one‐handed helicity of the PPI arms. Moreover, the hybrid magnetic nanoparticle can be alternatively synthesized via “grafting onto” strategy. A triethoxysilanyl‐terminated single handed helical PPI bearing l‐alanine ester pendants is prepared and grafted onto the surface of Fe3O4 nanoparticle. The generated hybrid magnetic nanoparticles show both magnetic character and optical activity. Taking advantage of these properties, they can be used in enantioselective crystallization of racemic threonine. The enantiomeric excess (ee) of the induced crystals is up to 93%. Moreover, the nanoparticles can be facilely recovered and recycle used for at least four times in enantioselective crystallization without significantly loss of its enantioselectivity.
Optically active and magnetic nanoparticles carrying Fe3O4 core and helical poly(phenyl isocyanide) arms are prepared via both “grafting from” and “grafting onto” strategies. This nanoparticle shows good performance in enantioselective crystallization and the enantiomeric excess of the induced crystal is up to 93%. Moreover, the nanoparticles can be readily recovered and recycled with the assistance of an external magnet.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
•Computational approaches improve the machining precision of 5-axis flank milling of spiral bevel gears.•A geometric method approximates the contact path of a gear pair without conducting tooth ...contact analysis (TCA).•An optimization scheme generates tool paths that induce minimal geometrical errors on the finished surface.•Three measures of the meshing performance are cross-compared on different gear pairs to verify their effectiveness.
Spiral bevel gears are a critical component in mechanical systems that offers high power transmission efficiency between nonparallel axes. The current gear manufacturing, which normally requires specialized machines and cutting tools specific to one gear type, offers limited production flexibility. An effective alternative is to utilize 5-axis computer numerical control milling on general-purpose machine tools. This paper aims to improve the machining precision in the flank milling of spiral bevel gears, particularly the tooth surfaces, using computational approaches. First, a geometric method was developed to approximate the contact path of a gear pair without solving the complex equations in tooth contact analysis. A quantitative measure was introduced to evaluate the contact path deviation from the center curve of the tooth surface. Second, we proposed an optimization scheme for generating tool paths that induce minimal geometrical errors on the finished surface. It employs a metaheuristics-based search algorithm with the errors as an objective in tool path planning. Test results on real gears verified the effectiveness of the proposed scheme. Three measures of the meshing performance, namely the average sampling error, the contact path deviation, and the transmission error, were cross-compared on different gear pairs to examine whether they consistently distinguish the performance rank. This work provides feasible solutions for controlling machining errors in 5-axis flank milling of complex gears.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Erinacine A, derived from the mycelia of Hericium erinaceus, has attracted much attention due to its neuroprotective properties. However, very few studies have been conducted on the bioavailability, ...tissue distribution, and protein binding of erinacine A. This study aimed to investigate the bioavailability, tissue distribution, and protein binding of erinacine A in Sprague-Dawley rats. After oral administration (po) and intravenous administration (iv) of 2.381 g/kg BW of the H. erinaceus mycelia extract (equivalent to 50 mg/kg BW of erinacine A) and 5 mg/kg BW of erinacine A, respectively, the absolute bioavailability of erinacine A was estimated as 24.39%. Erinacine A was detected in brain at 1 h after oral dosing and reached the peak at 8 h. Protein binding assay showed unbound erinacine A fractions in brain to blood ratio is close to unity, supporting passive diffusion as the dominating transport. Feces was the major route for the elimination of erinacine A. This study is the first to show that erinacine A can penetrate the blood-brain barrier of rats by the means of passive diffusion and thus support the development of H. erinaceus mycelia for the improvement of neurohealth.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
An intramedullary mass Yang, Jun-Song; Chu, Lei; Yan, Liang ...
BMJ (Online),
09/2021, Volume:
374
Journal Article
Peer reviewed
Gadolinium enhanced MRI of the thoracic spine (sagittal plane) showing a “target” sign—a ring enhancing intramedullary lesion with a clear border measuring 0.8 cm×3.0 cm×0.8 cm (red arrows) and ...central hypointensity (black arrow) Questions 1. Evidence from some case reports suggests that conventional anti-tuberculosis therapy can enable complete recovery.25 However, other reports show that early surgical decompression is more effective in patients with spinal cord compression, worsening neurological function, or lesion enlargement despite standard drug treatment.6789 Learning point Consider intraspinal tuberculosis in patients with a history of tuberculosis infection and neurological symptoms. ...details of The BMJ policy on financial interests are here: https://www.bmj.com/about-bmj/resources-authors/forms-policies-and-checklists/declaration-competing-interests Provenance and peer review: not commissioned; externally peer reviewed. 1 du Plessis J Andronikou S Theron S Wieselthaler N Hayes M. Unusual forms of spinal tuberculosis.