Au-Pd separation enhances bimetallic catalysis of alcohol oxidation.

In oxidation reactions catalysed by supported metal nanoparticles with oxygen as the terminal oxidant, the rate of the oxygen reduction can be a limiting factor. This is exemplified by the oxidative dehydrogenation of alcohols, an important class of reactions with modern commercial applications1-3. Supported gold nanoparticles are highly active for the dehydrogenation of the alcohol to an aldehyde4 but are less effective for oxygen reduction5,6. By contrast, supported palladium nanoparticles offer high efficacy for oxygen reduction5,6. This imbalance can be overcome by alloying gold with palladium, which gives enhanced activity to both reactions7,8,9; however, the electrochemical potential of the alloy is a compromise between that of the two metals, meaning that although the oxygen reduction can be improved in the alloy, the dehydrogenation activity is often limited. Here we show that by separating the gold and palladium components in bimetallic carbon-supported catalysts, we can almost double the reaction rate compared with that achieved with the corresponding alloy catalyst. We demonstrate this using physical mixtures of carbon-supported monometallic gold and palladium catalysts and a bimetallic catalyst comprising separated gold and palladium regions. Furthermore, we demonstrate electrochemically that this enhancement is attributable to the coupling of separate redox processes occurring at isolated gold and palladium sites. The discovery of this catalytic effect-a cooperative redox enhancement-offers an approach to the design of multicomponent heterogeneous catalysts.

Layer-By-Layer Designed Spark-Type AuCuPt Alloy with Robust Broadband Absorption to Enhance Sensitivity in Flexible Detection of Estriol by a Lateral Flow Immunoassay.

Excessive intake of estrogen poses significant health risks to the human body; hence, there is a necessity to develop rapid detection methods to monitor its levels of addition. Gold nanoparticles (AuNPs), commonly utilized as colorimetric signal labels, find extensive application in lateral flow immunoassay (LFIA). However, the detection sensitivity of traditional AuNPs-LFIA is typically constrained by low molar extinction coefficients and reliance on a single signal. Herein, in this work, unique spark-type AuCuPt nanoflowers modified with tannic acid (AuCuPt@TA) were precisely designed by reasonable layer-by-layer element composition and green modification. The obtained AuCuPt displays robust broadband absorption spanning the visible to near-infrared spectrum, showcasing a notable molar extinction coefficient of 2.38 × 1012 M-1 cm-1 and a photothermal conversion efficiency of 48.5%. Based on this, selecting estriol (E3) as a model analyte, colorimetric/photothermal dual-signal LFIA (CLFIA and PLFIA) was developed. Limits of detection (LOD) of the CLFIA and PLFIA were achieved at 0.033 ng mL-1 and 0.021 ng mL-1, respectively, which represent a 9.3- and 14.6-fold improvement compared to the visual LOD of AuNPs-LFIA. Moreover, the application feasibility of the immunoassay was further evaluated in the milk and pork with satisfactory recoveries ranging from 86.21% to 117.91%. Thus, this work has enhanced the performance of LFIA for E3 detection and exhibited enormous potential for other sensing platform construction.

Construct a Magnetic Pt/Ru Alloy Peroxidase Mimic As a Reusable and Cost-Effective "Signal-Off" Sensing Platform for Sensitive and Wide-Linear-Range Assay.

"Signal-off" nanozyme sensing platforms are usually employed to detect analytes (e.g., ascorbic acid (AA) and alkaline phosphatase (ALP)), which are mostly based on oxidase (OXD) nanozymes. However, their drawbacks, like dissolved oxygen-dependent catalysis capability, relatively low enzyme activity, limited amount, and kind, may not favor sensing platforms' optimization. Meanwhile, with the need for sustainable development, a reusable "signal-off" sensing platform is essential for cutting down the cost of the assay, but it is rarely developed in previous studies. Magnetic peroxidase (POD) nanozymes potentially make up the deficiencies and become reusable and better "signal-off" sensing platforms. As a proof of concept, we first construct Fe3O4@polydopamine-supported Pt/Ru alloy nanoparticles (IOP@Pt/Ru) without stabilizers. IOP@Pt/Ru shows high POD activity with Vmax of 83.24 × 10-8 M·s-1 for 3,3',5,5'-Tetramethylbenzidine (TMB) oxidation. Meanwhile, its oxidation rate for TMB is slower than the reduction of oxidized TMB by reducers, favorable for a more significant detection signal. On the other hand, IOP@Pt/Ru possesses great magnet-responsive capability, making itself be recycled and reused for at least 15-round catalysis. When applying IOP@Pt/Ru for AA (ALP) detection, it performs better detectable adaptability, with a linear range of 0.01-0.2 mM (0.1-100 U/L) and a limit of detection of 0.01 mM (0.05 U/L), superior to most of OXD nanozyme-based ALP sensing platform. Finally, IOP@Pt/Ru's reusable assay was demonstrated in real blood samples for ALP assay, which has never been explored in previous studies. Overall, this study develops a reusable "signal-off" nanozyme sensing platform with superior assay capabilities than traditional OXD nanozymes, paves a new way to optimize nanozyme-based "signal-off" sensing platforms, and provides an idea for constructing inexpensive and sustainable sensing platforms.

A Pt1Pd Single-Atom Alloy Nanozyme with Boosted Enzyme-Like Activity for Efficient Photo-Mediated Tumor Therapy.

Single-atom nanozymes (SAzymes) are emerging natural enzyme mimics and have attracted much attention in the biomedical field. SAzymes with Metal─Nx sites designed on carbon matrixes are currently the mainstream in research. It is of great significance to further expand the types of SAzymes to enrich the nanozyme library. Single-atom alloys (SAAs) are a material in which single-atom metal sites are dispersed onto another active metal matrix, and currently, there is limited research on their enzyme-like catalytic performance. In this work, a biodegradable Pt1Pd SAA is fabricated via a simple galvanic replacement strategy, and for the first time reveals its intrinsic enzyme-like catalytic performance including catalase-, oxidase-, and peroxidase-like activities, as well as its photodynamic effect. Experimental characterizations demonstrate that the introduction of single-atom Pt sites contributes to enhancing the affinity of Pt1Pd single-atom alloy nanozyme (SAAzyme) toward substrates, thus exhibiting boosted catalytic efficiency. In vitro and in vivo experiments demonstrate that Pt1Pd SAAzyme exhibits a photo-controlled therapeutic effect, with a tumor inhibition rate of up to 100%. This work provides vital guidance for opening the research direction of SAAs in enzyme-like catalysis.

3D printed microfluidic valve on PCB for flow control applications using liquid metal.

Direct 3D printing of active microfluidic elements on PCB substrates enables high-speed fabrication of stand-alone microdevices for a variety of health and energy applications. Microvalves are key components of microfluidic devices and liquid metal (LM) microvalves exhibit promising flow control in microsystems integrated with PCBs. In this paper, we demonstrate LM microvalves directly 3D printed on PCB using advanced digital light processing (DLP). Electrodes on PCB are coated by carbon ink to prevent alloying between gallium-based LM plug and copper electrodes. We used DLP 3D printers with in-house developed acrylic-based resins, Isobornyl Acrylate, and Diurethane Dimethacrylate (DUDMA) and functionalized PCB surface with acrylic-based resin for strong bonding. Valving seats are printed in a 3D caterpillar geometry with chamber diameter of 700 µm. We successfully printed channels and nozzles down to 90 µm. Aiming for microvalves for low-power applications, we applied square-wave voltage of 2 Vpp at a range of frequencies between 5 to 35 Hz. The results show precise control of the bistable valving mechanism based on electrochemical actuation of LMs.

Bimetallic Gold/Silver and Bioactive Camptothecin Hybrid Nanoparticles for Eradication of Cancer Stem Cells in a Combination Manner.

The defeat of cancer is still a challenge due to the existence of cancer stem cells (CSCs) because they resist conventional chemotherapy via multifactor regulated mechanisms. Consequently, one-dimensional action toward CSCs cannot work. Herein, we used rationally designed hybrid nanoparticles as a combined cancer therapy, hoping to form a multidimensional control network. In this paper, gold/silver alloy nanoparticle decorated camptothecin nanocrystals were formulated according to complementary anti-CSC mechanisms from gold, silver, and organic drug. This smart drug formulation could combine chemotherapy and thermotherapy, target different tumor sites, and demonstrate versatile toxicity profiles from each component. Major results indicated that this nanosystem demonstrated indiscriminately effective cytotoxic/proapoptotic/necrotic activity against bulk MCF-7 cells and their CSC subpopulation, in particular under laser ablation. Moreover, this nanosystem displayed enhanced antineoplastic activity against CSC spheroids, resulting in a significant reduction in their number and size, that is, their self-renewal capacity. All the results indicated that CSCs upon treatment of these new hybrid nanoparticles underwent reduced stemness and conversion from the original quiescent state and recovered their sensitivity toward chemotherapy. The relevant anticancer mechanism was ascribed to NIR-pH dual responsive drug release, synergistic/combined thermo-chemotherapy of organic drug and inorganic alloy nanoparticles, enhanced cellular uptake mediated by alloy nanoparticles, and Ag+-induced biomembrane damage. This thermo-chemotherapy platform provides a new combinatorial strategy for inorganic and organic agents in the complete elimination of CSCs.

Alloyed Trimetallic Nanocomposite as an Efficient and Recyclable Solid Matrix for Ideonella sakaiensis Lipase Immobilization.

In this work, a trimetallic (Ni/Co/Zn) organic framework (tMOF), synthesized by a solvothermal method, was calcinated at 400 and 600 °C and the final products were used as a support for lipase immobilization. The material annealed at 400 °C (Ni-Co-Zn@400) had an improved surface area (66.01 m2/g) and pore volume (0.194 cm3/g), which showed the highest enzyme loading capacity (301 mg/g) with a specific activity of 0.196 U/mg, and could protect the enzyme against thermal denaturation at 65 °C. The optimal pH and temperature for the lipase were 8.0 and 45 °C but could tolerate pH levels 7.0-8.0 and temperatures 40-60 °C. Moreover, the immobilized enzyme (Ni-Co-Zn@Lipase, Ni-Co-Zn@400@Lipase, or Ni-Co-Zn@600@Lipase) could be recovered and reused for over seven cycles maintaining 80, 90, and 11% of its original activity and maintained a residual activity >90% after 40 storage days. The remarkable thermostability and storage stability of the immobilized lipase suggest that the rigid structure of the support acted as a protective shield against denaturation, while the improved pH tolerance toward the alkaline range indicates a shift in the ionization state attributed to unequal partitioning of hydroxyl and hydrogen ions within the microenvironment of the active site, suggesting that acidic residues may have been involved in forming an enzyme-support bond. The high enzyme loading capacity, specific activity, encouraging stability, and high recoverability of the tMOF@Lipase indicate that a multimetallic MOF could be a better platform for efficient enzyme immobilization.

Prospective evaluation of ultrasound features of magnesium-based bioabsorbable screw resorption in pediatric fractures.

OBJECTIVE: Bioabsorbable magnesium-based alloy screws release gas upon resorption. The resulting findings in the adjacent soft tissues and joints may mimic infection. The aim of the study was to evaluate the ultrasound (US) findings in soft tissues and joints during screw resorption. METHODS: Prospectively acquired US studies from pediatric patients treated with magnesium screws were evaluated for screw head visibility, posterior acoustic shadowing, twinkling artifact, foreign body granuloma, gas (soft tissue, intra-articular), alterations of the skin and subcutaneous fat, perifascial fluid, localized fluid collections, hypervascularization, and joint effusion. RESULTS: Sixty-six US studies of 28 pediatric patients (nfemale = 9, nmale = 19) were included. The mean age of the patients at the time of surgery was 10.84 years; the mean time between surgery and ultrasound was 128.3 days (range = 6-468 days). The screw head and posterior acoustic shadowing were visible in 100% of the studies, twinkling artifact in 6.1%, foreign body granuloma in 92.4%, gas locules in soft tissue in 100% and intra-articular in 18.2%, hyperechogenicity of the subcutaneous fat in 90.9%, cobblestoning of the subcutaneous fat in 24.2%, loss of normal differentiation between the epidermis/dermis and the subcutaneous fat in 57.6%, localized fluid collection in 9.9%, perifascial fluid in 12.1%, hypervascularization in 27.3%, and joint effusion in 18.2%. CONCLUSION: US findings in pediatric patients treated with magnesium screws strongly resemble infection, but are normal findings in the setting of screw resorption. CLINICAL RELEVANCE STATEMENT: Bioabsorbable magnesium-based alloy screws release gas during resorption. The resulting US findings in the adjacent soft tissues and joints in pediatric patients may mimic infection, but are normal findings. KEY POINTS: • Bioabsorbable magnesium-based alloy screws release gas upon resorption. • The resulting ultrasound findings in children's soft tissues and joints closely resemble those of soft tissue infection or osteosynthesis-associated infection. • Be familiar with these ultrasound findings in order to avoid inadvertently misdiagnosing a soft tissue infection or osteosynthesis-associated infection.

Early Outcomes of Interwoven Nitinol Wire Stent Placement versus Endarterectomy for the Treatment of Atherosclerotic Disease of the Common Femoral Artery.

PURPOSE: To compare the clinical outcomes of common femoral artery (CFA) atherosclerotic disease treated with either surgical endarterectomy or an interwoven nitinol wire stent system. MATERIALS AND METHODS: A retrospective review was conducted of all patients with chronic, de novo atherosclerotic CFA disease treated with surgical endarterectomy (CFAE) or stent placement between July 2019 and March 2022. Outcome measures assessed up to 12 months after procedure included clinical improvement, primary restenosis, target vessel revascularization (TVR), major adverse limb events (MALEs), and all-cause mortality. RESULTS: Thirty-nine stents were deployed in 33 patients, and 56 CFAEs were performed in 55 patients. No differences were noted in the rate of primary patency (95.5% vs 94.4%, P = .618), TVR (2.9% vs 1.8%, P = .777), MALE (5.1% vs 5.4%, P = .949), and all-cause mortality (14.1% vs 3.6%, P = .076) between the stent and CFAE groups up to 12 months after procedure. There was greater improvement in median clinical severity in the stent group than in the CFAE group (Rutherford score change of 3.0 vs 1.5, P = .013). The median length of stay was less for the stent group (3 vs 7 days, P = .002), and there was a lower likelihood of severe or disabling adverse events in the stent group (0 vs 9 cases, P = .010). CONCLUSIONS: Patients treated with an interwoven nitinol wire stent had patency rates comparable to those treated with CFAE while having a lower incidence of severe adverse events and a shorter length of hospital stay than those who underwent CFAE.

The BioMimics 3D Helical Centreline Nitinol Stent in Chronic Limb Threatening Ischaemia and Complex Lesions: Three Year Outcomes of the MIMICS-3D Registry.

OBJECTIVE: There is a need for improved outcomes in the endovascular treatment of patients suffering from chronic limb threatening ischaemia (CLTI), highly calcified lesions, and chronic total occlusions (CTOs). The helical centreline self expanding BioMimics 3D stent might be particularly useful in these high risk subsets, combining flexibility and fracture resistance with radial strength. Herein, the performance of the BioMimics 3D stent was assessed in these high risk subsets. METHODS: MIMICS-3D is a prospective, multicentre, European real world registry. This was a post hoc analysis, comparing patients with CLTI vs. intermittent claudication (IC), lesions with bilateral calcification vs. those without (peripheral arterial calcium scoring system [PACSS] 3,4 vs. PACSS 0 - 2), and CTO vs. no CTO. Propensity score matching was performed to reduce the impact of baseline variables. The 36 month endpoints were clinically driven target lesion revascularisation (CD-TLR), death, major target limb amputation, and stent patency. RESULTS: A total of 507 patients were enrolled. At 36 months, patients with CLTI had lower freedom from major amputation than patients with IC (92.6% vs. 100%, p < .001). In terms of primary patency, patients with CTO had lower patency rates than those without (63.9% vs. 77.8%, p = .003), but the difference reduced after propensity score matching (70.5% vs. 76.8%, p = .43). Primary patency was not impaired for patients with PACSS 3,4 or patients with CLTI. Freedom from CD-TLR was not significantly different among the groups and was 73.8% for CLTI vs. 78.9% for IC (p = .15), 77.6% for PACSS 3,4 vs. 78.7% for PACSS 0 - 2 (p = .55), and 75.6% for CTO vs. 81.0% for no CTO (p = .11). CONCLUSIONS: The outcome of the MIMICS-3D registry suggests that the BioMimics 3D stent is effective in the endovascular treatment of complex femoropopliteal lesions and in CLTI. Future randomised controlled trials should confirm its non-inferiority or superiority compared with existing alternatives.

Highly Sensitive, Stable InP Quantum Dot Fluorescent Probes for Quantitative Immunoassay Through Nanostructure Tailoring and Biotin-Streptavidin Coupling.

Nontoxic, highly sensitive InP quantum dot (QD) fluorescent immunoassay probes are promising biomedical detection modalities due to their unique properties. However, InP-based QDs are prone to surface oxidation, and the stability of InP QD-based probes in biocompatible environments remains a crucial challenge. Although the thick shell can provide some protection during the phase transfer process of hydrophobic QDs, the photoluminescence quantum yield (PLQY) is generally decreased because of the contradiction between lattice stress relaxation and thick shell growth. Herein, we developed thick-shell InP-based core/shell QDs by inserting a ZnSeS alloy layer. The ternary ZnSeS intermediate shell could effectively facilitate lattice stress relaxation and passivate the defect states. The synthesized InP/ZnSe/ZnSeS/ZnS core/alloy shell/shell QDs (CAS-InP QDs) with nanostructure tailoring revealed a larger size, high PLQY (90%), and high optical stability. After amphiphilic polymer encapsulation, the aqueous CAS-InP QDs presented almost constant fluorescence attenuation and stable PL intensity under different temperatures, UV radiation, and pH solutions. The CAS-InP QDs were excellent labels of the fluorescence-linked immunosorbent assay (FLISA) for detecting C-reactive protein (CRP). The biotin-streptavidin (Bio-SA) system was first introduced in the FLISA to further improve the sensitivity, and the CAS-InP QDs-based SA-Bio sandwich FLISA realized the detection of CRP with an impressive limit of detection (LOD) of 0.83 ng/mL. It is believed that the stable and sensitive InP QD fluorescent probes will drive the rapid development of future eco-friendly, cost-effective, and sensitive in vitro diagnostic kits.

Dilute Alloys Based on Au, Ag, or Cu for Efficient Catalysis: From Synthesis to Active Sites.

The development of new catalyst materials for energy-efficient chemical synthesis is critical as over 80% of industrial processes rely on catalysts, with many of the most energy-intensive processes specifically using heterogeneous catalysis. Catalytic performance is a complex interplay of phenomena involving temperature, pressure, gas composition, surface composition, and structure over multiple length and time scales. In response to this complexity, the integrated approach to heterogeneous dilute alloy catalysis reviewed here brings together materials synthesis, mechanistic surface chemistry, reaction kinetics, in situ and operando characterization, and theoretical calculations in a coordinated effort to develop design principles to predict and improve catalytic selectivity. Dilute alloy catalysts─in which isolated atoms or small ensembles of the minority metal on the host metal lead to enhanced reactivity while retaining selectivity─are particularly promising as selective catalysts. Several dilute alloy materials using Au, Ag, and Cu as the majority host element, including more recently introduced support-free nanoporous metals and oxide-supported nanoparticle "raspberry colloid templated (RCT)" materials, are reviewed for selective oxidation and hydrogenation reactions. Progress in understanding how such dilute alloy catalysts can be used to enhance selectivity of key synthetic reactions is reviewed, including quantitative scaling from model studies to catalytic conditions. The dynamic evolution of catalyst structure and composition studied in surface science and catalytic conditions and their relationship to catalytic function are also discussed, followed by advanced characterization and theoretical modeling that have been developed to determine the distribution of minority metal atoms at or near the surface. The integrated approach demonstrates the success of bridging the divide between fundamental knowledge and design of catalytic processes in complex catalytic systems, which can accelerate the development of new and efficient catalytic processes.

General Entropy Approach Toward Ultratough Sustainable Plastics.

Entropy is a universal concept across the physics of mixtures. While the role of entropy in other multicomponent materials has been appreciated, its effects in polymers and plastics have not. In this work, it is demonstrated that the seemingly small mixing entropy contributes to the miscibility and performance of polymer alloys. Experimental and modeling studies on over 30 polymer pairs reveal a strong correlation between entropy, morphology, and mechanical properties, while elucidating the mechanism behind: in polymer blends with weak interactions, entropy leads to homogeneously dispersed nanosized domains stabilized by highly entangled chains. This unique microstructure promotes uniform plastic deformation at the interface, thus improving the toughness of conventional brittle polymers by 1-2 orders of magnitude without sacrificing other properties, analogous to high-entropy metallic alloys. The proposed strategy also applies to ternary polymer systems and copolymers, offering a new pathway toward the development of sustainable polymers.

Design and preparation of Ti-xFe antibacterial titanium alloys based on micro-area potential difference.

Fe was selected as an alloying element for the first time to prepare a new antibacterial titanium alloy based on micro-area potential difference (MAPD) antibacterial mechanism. The microstructure, the corrosion resistance, the mechanical properties, the antibacterial properties and the cell biocompatibility have been investigated in detail by optical microscopy, scanning electron microscopy, electrochemical testing, mechanical property test, plate count method and cell toxicity measurement. It was demonstrated that heat treatment had a significant on the compressive mechanical properties and the antibacterial properties. Ti-xFe (x = 3,5 and 9) alloys after 850 °C/3 h + 550 °C/62 h heat treatment exhibited strong antimicrobial properties with an antibacterial rate of more than 90% due to the MAPD caused by the redistribution of Fe element during the aging process. In addition, the Fe content and the heat treatment process had a significant influence on the mechanical properties of Ti-xFe alloy but had nearly no effect on the corrosion resistance. All Ti-xFe alloys showed non-toxicity to the MC3T3 cell line in comparison with cp-Ti, indicating that the microzone potential difference had no adverse effect on the corrosion resistance, cell proliferation, adhesion, and spreading. Strong antibacterial properties, good cell compatibility and good corrosion resistance demonstrated that Ti-xFe alloy might be a candidate titanium alloy for medical applications.

Black phosphorus-incorporated novel Ti-12Mo-10Zr implant for multimodal treatment of osteosarcoma.

The repair and reconstruction of large bone defects after bone tumor resection is still a great clinical challenge. At present, orthopedic implant reconstruction is the mainstream treatment for repairing bone defects. However, according to clinical feedback, local tumor recurrence and nonunion of bone graft are common reasons leading to the failure of bone defect repair and reconstruction after bone tumor resection, which seriously threaten the physical and mental health of patients. On this basis, here the self-developed low modulus Ti-12Mo-10Zr alloy (TMZ) was chosen as substrate material. To improve its biological activity and osteointegration, calcium, oxygen, and phosphorus co-doped microporous coating was prepared on TMZ alloy by microarc oxidation (MAO). Then, black phosphorus (BP) nanosheets were incorporated onto MAO treated TMZ alloy to obtain multifunctional composites. The obtained BP-MAO-TMZ implant exhibited excellent photothermal effects and effective ablation of osteosarcoma cancer cells under the irradiation of 808 nm near infrared laser, while no photothermal or therapeutic effects were observed for TMZ alloy. Meanwhile, the structure/component bionic coating obtained after MAO treatment as well as the P-driven in situ biomineralization performance after incorporation of BP nanosheets endowed BP-MAO-TMZ implant with synergistic promoting effect on MC3T3-E1 osteoblasts' activity, proliferation and differentiation ability. This study is expected to provide effective clinical solutions for problems of difficult bone regeneration and tumor recurrence after tumor resection in patients with bone tumors and to solve a series of medical problems such as poor prognosis and poor postoperative quality of patients life with malignant bone tumors.

Active superelasticity in three-dimensional epithelia of controlled shape.

Fundamental biological processes are carried out by curved epithelial sheets that enclose a pressurized lumen. How these sheets develop and withstand three-dimensional deformations has remained unclear. Here we combine measurements of epithelial tension and shape with theoretical modelling to show that epithelial sheets are active superelastic materials. We produce arrays of epithelial domes with controlled geometry. Quantification of luminal pressure and epithelial tension reveals a tensional plateau over several-fold areal strains. These extreme strains in the tissue are accommodated by highly heterogeneous strains at a cellular level, in seeming contradiction to the measured tensional uniformity. This phenomenon is reminiscent of superelasticity, a behaviour that is generally attributed to microscopic material instabilities in metal alloys. We show that in epithelial cells this instability is triggered by a stretch-induced dilution of the actin cortex, and is rescued by the intermediate filament network. Our study reveals a type of mechanical behaviour-which we term active superelasticity-that enables epithelial sheets to sustain extreme stretching under constant tension.

Processing bulk natural wood into a high-performance structural material.

Synthetic structural materials with exceptional mechanical performance suffer from either large weight and adverse environmental impact (for example, steels and alloys) or complex manufacturing processes and thus high cost (for example, polymer-based and biomimetic composites). Natural wood is a low-cost and abundant material and has been used for millennia as a structural material for building and furniture construction. However, the mechanical performance of natural wood (its strength and toughness) is unsatisfactory for many advanced engineering structures and applications. Pre-treatment with steam, heat, ammonia or cold rolling followed by densification has led to the enhanced mechanical performance of natural wood. However, the existing methods result in incomplete densification and lack dimensional stability, particularly in response to humid environments, and wood treated in these ways can expand and weaken. Here we report a simple and effective strategy to transform bulk natural wood directly into a high-performance structural material with a more than tenfold increase in strength, toughness and ballistic resistance and with greater dimensional stability. Our two-step process involves the partial removal of lignin and hemicellulose from the natural wood via a boiling process in an aqueous mixture of NaOH and Na2SO3 followed by hot-pressing, leading to the total collapse of cell walls and the complete densification of the natural wood with highly aligned cellulose nanofibres. This strategy is shown to be universally effective for various species of wood. Our processed wood has a specific strength higher than that of most structural metals and alloys, making it a low-cost, high-performance, lightweight alternative.

Establishment of an Animal Model of Dog Bite Injuries.

Nowadays dog bite is becoming a world public health problem. Therefore, the study aimed to develop a dog bite animal model that is helpful to solve these problems. In this study, the skull of an adult dog was scanned. The three-dimensional model of the dog maxillofacial bones and dentition was built by MIMICS. Next, the model was printed with Co-Cr alloy by using selective laser sintering technology to develop the dog bite simulation pliers. Then, to simulate dog bite to most, the maximum bite force of the pliers was measured and actions contained in dog bite process was analyzed. Afterwards, according to action analysis results, rabbits were bitten by the prepared instrument in actions that simulate dog's bite. Finally, the reproducibility and controllability of this animal model of dog bite injuries was validated in an in vivo study. The results showed a reliable animal model of dog bite injuries has been developed in this study. The sites and severities of the injuries could be adjusted as the operator wishes and the animal model of dog bite injuries was highly repeatable. This study also indicates the feasibility of using digital technology in establishing animal bite models.

Initial arch wires used in orthodontic treatment with fixed appliances.

BACKGROUND: Initial arch wires are the first arch wires inserted into fixed appliance at the beginning of orthodontic treatment. With a number of different types of orthodontic arch wires available for initial tooth alignment, it is important to understand which are most efficient and which cause the least amount of root resorption and pain during the initial aligning stage of treatment. This is the third update of a Cochrane review first published in 2010. OBJECTIVES: To assess the effects of initial arch wires for the alignment of teeth with fixed orthodontic braces, in terms of the rate of tooth alignment, amount of root resorption accompanying tooth movement, and intensity of pain experienced by patients during the initial alignment stage of treatment. SEARCH METHODS: We searched Cochrane Oral Health's Trials Register, CENTRAL, MEDLINE, Embase, and two ongoing trials registries on 4 July 2022. SELECTION CRITERIA: We included randomised controlled trials (RCTs) of different initial arch wires used to align teeth with fixed orthodontic braces. We included people with full-arch fixed orthodontic appliances on the upper arch, lower arch, or both arches. DATA COLLECTION AND ANALYSIS: Two independent review authors were responsible for study selection, data extraction, and assessment of risk of bias in included studies. We contacted corresponding authors of included studies to obtain missing information. We resolved disagreements by discussion between the review authors. Our main outcomes were alignment rate (movement of teeth in mm), root resorption, time to alignment, and intensity of pain measured on a 100-mm visual analogue scale (VAS). We pooled data from studies with similar interventions and outcomes using random-effects models. We reported mean differences (MDs) with 95% confidence intervals (CIs) for continuous data, risk ratios (RRs) with 95% CIs for dichotomous data, and alignment rate ratios with 95% CIs for time-to-event data. Two independent review authors assessed the certainty of evidence. We resolved disagreements by discussion between the review authors. MAIN RESULTS: We included 29 RCTs with 1915 participants (2581 arches) in this review. Studies were generally small (sample sizes ranged from 14 to 200 participants). Duration of follow-up varied between three days and six months. Eleven studies received funding, six received no funding, and 12 provided no information about funding sources. We judged eight studies at high risk of bias, nine at low risk, and 12 at unclear risk. We grouped the studies into six main comparisons. Multistrand stainless steel wires versus wires composed of other materials Six studies with 409 participants (545 arches) evaluated multistrand stainless steel (StSt) wires versus wires composed of other materials. We are very uncertain about the effect of multistrand StSt wires versus other wires on alignment rate (4 studies, 281 participants, 417 arches; very low-certainty evidence). There may be little to no difference between multistrand StSt wires and other wires in terms of intensity of pain (MD -2.68 mm, 95% CI -6.75 to 1.38; 2 studies, 127 participants, 127 arches; low-certainty evidence). Conventional nickel-titanium wires versus superelastic nickel-titanium wires Four studies with 266 participants (274 arches) evaluated conventional nickel-titanium (NiTi) wires versus superelastic NiTi wires. There may be little to no difference between the different wire types in terms of alignment rate (124 participants, 124 arches, 2 studies; low-certainty evidence) and intensity of pain (MD -0.29 mm, 95% CI -1.10 to 0.52; 2 studies, 142 participants, 150 arches; low-certainty evidence). Conventional nickel-titanium wires versus thermoelastic copper-nickel-titanium wires Three studies with 210 participants (210 arches) evaluated conventional Ni-Ti versus thermoelastic copper-nickel-titanium (CuNiTi) wires. We are very uncertain about the effects of the different arch wires on alignment rate (1 study, 66 participants, 66 arches; very low-certainty evidence). There may be little to no difference between conventional NiTi wires and thermoelastic CuNiTi wires in terms of time to alignment (alignment rate ratio 1.30, 95% CI 0.68 to 2.50; 1 study, 60 participants, 60 arches; low-certainty evidence). Superelastic nickel-titanium wires versus thermoelastic nickel-titanium wires Twelve studies with 703 participants (936 arches) evaluated superelastic NiTi versus thermoelastic NiTi wires. There may be little to no difference between superelastic NiTi wires and thermoelastic NiTi wires in alignment rate at four weeks (MD -0.28 mm, 95% CI 0.62 to 0.06; 5 studies, 183 participants, 183 arches; low-certainty evidence). We are very uncertain about the effects of the different wires on root resorption (2 studies, 52 participants, 312 teeth; very low-certainty evidence). Superelastic NiTi wires compared with thermoelastic NiTi wires may result in a slight increase in time to alignment (MD 0.5 months, 95% CI 0.21 to 0.79; 1 study, 32 participants, 32 arches; low-certainty evidence) but are probably associated with a slight increase in intensity of pain (MD 6.96 mm, 95% CI 1.82 to 12.10; 3 studies, 94 participants, 138 arches, moderate-certainty evidence). Single-strand superelastic nickel-titanium wires versus coaxial superelastic nickel-titanium wires Three studies with 104 participants (104 arches) evaluated single-strand superelastic NiTi versus coaxial superelastic NiTi wires. Use of single-strand superelastic NiTi wires compared with coaxial superelastic NiTi wires probably results in a slight reduction in alignment rate at four weeks (MD -2.64 mm, 95% CI -4.61 to -0.67; 2 studies, 64 participants, 64 arches, moderate-certainty evidence). Different sizes of nickel-titanium wires Two studies with 149 participants (232 arches) compared different types of NiTi wires. There may be little to no difference between different sizes of NiTi wires in terms of pain (low-certainty evidence). AUTHORS' CONCLUSIONS: Superelastic NiTi wires probably produce slightly more pain after one day than thermoelastic NiTi wires, and single-strand superelastic NiTi wires probably have a lower alignment rate over four weeks compared with coaxial superelastic NiTi wires. All other evidence on alignment rate, root resorption, time to alignment, and pain is of low or very low certainty in all comparisons. Therefore, there is insufficient evidence to determine whether any particular arch wire material or size is superior to any other. The findings of this review are imprecise and unreliable; well-designed larger studies are needed to give better estimates of the benefits and harms of different arch wires. Orthodontists should exercise caution when interpreting the findings of this review and be prepared to adapt their treatment plans based on individual patient needs.

Most recently developed polyester polymer alloy dialyzer: A new medium cut-off membrane?

BACKGROUND: New versions of the polyester polymer alloy (PEPA) membrane have appeared over the years, with increases in both the pore size and the amount of polyvinylpyrrolidone (PVP) to optimize hydrophilicity performance. This study aimed to assess the efficacy of the most recently developed PEPA dialyzer, the FDY series, in hemodialysis (HD) modality in terms of uremic toxin removal and albumin loss and to compare it with that of several high-flux dialyzers currently used in HD and post-dilution hemodiafiltration (HDF) treatments. METHODS: A prospective study was carried out in 21 patients. All patients underwent six dialysis sessions with the same routine dialysis parameters; only the dialyzer and/or the dialysis modality varied: FX80 in HD, FDY 180 in HD, Clearum HS17 in HDF, Elisio 19H in HDF, Vitapes 180 in HDF, and FX80 in post-dilution HDF. The reduction ratios (RR) of urea, creatinine, ß2-microglobulin, myoglobin, κFLC, prolactin, α1-microglobulin, α1-acid glycoprotein, λFLC, and albumin were compared intraindividually. Dialysate albumin loss was also measured. RESULTS: Both membranes FDY and FX80 are high-flux dialyzers and are applied here in high-flux HD. The average RR of ß2-microglobulin was slightly lower in the two HD treatments than in the HDF treatments. Comparison of dialysis treatments revealed that the PEPA FDY dialyzer in the HD modality was more effective than the FX80 dialyzer in high-flux HD and was as effective as post-dilution HDF, especially in terms of myoglobin, κFLC, prolactin, α1-microglobulin, and λFLC RRs. The FDY treatments obtained similar albumin RR in blood and slightly higher dialysate albumin loss, although the values were clinically acceptable. CONCLUSIONS: The most recently developed PEPA dialyzers in the HD modality were as effective as all treatments in the HDF modality and were clearly superior to high-flux helixone HD treatment. These results confirm that this dialyzer should be categorized within the medium cut-off (MCO) membrane classification.