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1.
Rob Auton Syst ; 148: 103917, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34720413

RESUMO

The coronavirus disease 2019 (COVID-19) outbreak has increased mortality and morbidity world-wide. Oropharyngeal swabbing is a well-known and commonly used sampling technique for COVID-19 diagnose around the world. We developed a robot to assist with COVID-19 oropharyngeal swabbing to prevent frontline clinical staff from being infected. The robot integrates a UR5 manipulator, rigid-flexible coupling (RFC) manipulator, force-sensing and control subsystem, visual subsystem and haptic device. The robot has strength in intrinsically safe and high repeat positioning accuracy. In addition, we also achieve one-dimensional constant force control in the automatic scheme (AS). Compared with the rigid sampling robot, the developed robot can perform the oropharyngeal swabbing procedure more safely and gently, reducing risk. Alternatively, a novel robot control schemes called collaborative manipulation scheme (CMS) which combines a automatic phase and teleoperation phase is proposed. At last, comparative experiments of three schemes were conducted, including CMS, AS, and teleoperation scheme (TS). The experimental results shows that CMS obtained the highest score according to the evaluation equation. CMS has the excellent performance in quality, experience and adaption. Therefore, the proposal of CMS is meaningful which is more suitable for robot-sampling.

2.
J Colloid Interface Sci ; 606(Pt 1): 817-825, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34425269

RESUMO

The carbon pore structure could have a significant effect on supercapacitor performance; however, this effect has not yet been systematically studied. A facile approach for synthesizing porous, ultrathin carbon sheets while rationally tuning the ratio of micro-to meso-pores via partial corrosion has been developed for the fabrication of high-performance devices. The prepared carbon from biomass with an optimal ratio of micro- to meso-pores has a large specific surface area of 1785 m2 g -1, a high specific capacitance of 447F g -1 at 0.5 A g-1, a high energy density of 15.5-9.7 Wh kg-1, and an excellent power density of 0.062-6.24 kW kg-1. After 10,000 charge-discharge cycles, the capacitance retention was maintained at 95%, which exceeded most of the biomass-carbon-based capacitors. Volcano relationships were found to exist through plots of both specific surface area and specific capacitance versus the micro-to meso-pore ratio. An enhancement mechanism with a rational pore structure is proposed, which not only networks micropores to remove died-end micropores to achieve the largest specific active surface area and high specific capacitance but also realizes fast mass-transport channels, resulting in high power density. This work provides an effective approach based on waste re-use by tuning a rational pore structure for achieving high energy/power density toward green energy applications with universal significance.


Assuntos
Carbono , Biomassa , Capacitância Elétrica , Porosidade
3.
Chemosphere ; 287(Pt 4): 132430, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34600931

RESUMO

The heterogeneous reaction between formic acid and mineral dust play an important role in tropospheric chemistry. However, the molecular mechanism on formic acid uptake on mineral dust is not yet to be fully understood. In our work, a comprehensive and multiscale theoretical study (include density functional theory, DFT calculations and reactive molecular dynamics, RMD simulations) has been provided to investigate this heterogeneous reaction at molecular level. The results of DFT calculations show that the SiO2 and TiO2 particles have a strong tendency to adsorb formic acid to its surface, and the attractive part of the binding energy was dominated by electrostatic component. RMD simulations show that the uptake of formic acid and water on TiO2 particles would modified TiO2 particles, which formed Ti-OH and Ti-OCHO on particle surface. Besides, the formic acid coordination surface modes were dominated by the monodentate formate mode rather than bidentate formate mode. The molecular level study is helpful for understanding the accumulation of formic acid on mineral dust particles and global balance of atmospheric formic acid.


Assuntos
Óxidos , Dióxido de Silício , Formiatos , Minerais
4.
J Colloid Interface Sci ; 607(Pt 1): 281-289, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34507000

RESUMO

Exploring innovation strategies has huge potential to significantly improving both activity and stability of current catalysts. Here, a chainmail design is proposed to enable the electronic interaction of ultrathin nitrogen-doped carbon shell with Ni2P nanorod core arrayed on nickel foam (Ni2P@NC/NF) for simultaneously promoting the activity and stability in both alkaline and neutral hydrogen evolution reaction (HER). The easy penetration of valence electrons from active Ni2P core to NC shell enables the obvious improvement of HER performance compared to pure Ni2P. In 1 M KOH and 1 M PBS solution, the resultant Ni2P@NC/NF requires the ultralow overpotentials of only 93 and 96 mV to drive the current density of 10 mA cm-2 with the Faradaic efficiency of 96% and 94%, respectively. Remarkably, such a chainmail design also reveals an obviously improved stability with almost negligible performance degradation under the current density of 20 mA cm-2 for 30 h. Theoretical calculations confirm that the nitrogen-doped carbon shell improves the durability of transition metal phosphides by increasing the dissolution resistance of Ni atoms. The proposed concept may create a new pathway for synchronizing high activity and robust stability in manipulating heterogeneous catalytic properties.

5.
Sci Rep ; 11(1): 23127, 2021 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-34848736

RESUMO

A high-performing interpretable model is proposed to predict the risk of deterioration in coronavirus disease 2019 (COVID-19) patients. The model was developed using a cohort of 3028 patients diagnosed with COVID-19 and exhibiting common clinical symptoms that were internally verified (AUC 0.8517, 95% CI 0.8433, 0.8601). A total of 15 high risk factors for deterioration and their approximate warning ranges were identified. This included prothrombin time (PT), prothrombin activity, lactate dehydrogenase, international normalized ratio, heart rate, body-mass index (BMI), D-dimer, creatine kinase, hematocrit, urine specific gravity, magnesium, globulin, activated partial thromboplastin time, lymphocyte count (L%), and platelet count. Four of these indicators (PT, heart rate, BMI, HCT) and comorbidities were selected for a streamlined combination of indicators to produce faster results. The resulting model showed good predictive performance (AUC 0.7941 95% CI 0.7926, 0.8151). A website for quick pre-screening online was also developed as part of the study.

6.
Medicine (Baltimore) ; 100(45): e27818, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34766595

RESUMO

BACKGROUND: The incidence of proximal gastric cancer in the gastric fundus, cardia, and other parts is increasing rapidly. The purpose of this study was to systematically compare the short-term and long-term clinical effects of proximal gastrectomy with double tract reconstruction (PG-DTR) to total gastrectomy (TG) for proximal early gastric cancer (EGC). METHODS: A systematic review and meta-analysis was conducted through searching the literature in PubMed, Web of Science, Cochrane Library, EMBASE, CNKI, WAN FANG, and VIP databases. All clinical controlled trials and randomized controlled trials (RCTs) of PG-DTR and PG were included. Simultaneously, the relevant data were extracted, and the software RevMan version 5.1 was used for the meta-analysis. RESULTS: Eight studies with a total of 753 patients were eligible for the meta-analysis. There were no significant differences in the operation time, intraoperative blood loss, postoperative hospital stay, early complications (anastomotic fistula and anastomotic bleeding), late complications (reflux symptoms and anastomotic stenosis), and 5-year survival rate between PG-DTR and TG. However, the levels of partial nutritional indicators (vitamin B12 supplements and vitamin B12 deficiency) were significantly higher in the PG-DTR group than in the TG group. CONCLUSION: This study showed ample evidence to suggest that PG-DTR improved the postoperative nutritional status without compromising patient safety while providing the same surgical characteristics and postoperative morbidity as TG.

7.
Int J Mol Sci ; 22(21)2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34769376

RESUMO

Glutaredoxins (GRXs), important components of the intracellular thiol redox system, are involved in multiple cellular processes. In a previous study, we identified five GRXs in the apicomplexan parasite, Neospora caninum. In the present study, we confirmed that the GRXs S14 and C5 are located in the apicoplast, which suggests unique functions for these proteins. Although single-gene deficiency did not affect the growth of parasites, a double knockout (Δgrx S14Δgrx C5) significantly reduced their reproductive capacity. However, there were no significant changes in redox indices (GSH/GSSG ratio, reactive oxygen species and hydroxyl radical levels) in double-knockout parasites, indicating that grx S14 and grx C5 are not essential for maintaining the redox balance in parasite cells. Key amino acid mutations confirmed that the Cys203 of grx S14 and Cys253/256 of grx C5 are important for parasite growth. Based on comparative proteomics, 79 proteins were significantly downregulated in double-knockout parasites, including proteins mainly involved in the electron transport chain, the tricarboxylic acid cycle and protein translation. Collectively, GRX S14 and GRX C5 coordinate the growth of parasites. However, considering their special localization, the unique functions of GRX S14 and GRX C5 need to be further studied.

8.
Materials (Basel) ; 14(21)2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34772087

RESUMO

Compared with the conventional drainage strengthening techniques, the precast concrete segment assembly strengthening method (PCSAM) is regarded as a fast, more economical, and traffic-friendly underwater strengthening method for damaged bridge piers and piles, as the drainage procedure can be omitted. However, this method still has some disadvantages, such as strength loss of the filling material, debonding of the interface due to shrinkage of the filling material, poor connection effects, and poor durability of the segment sleeves. To solve these problems, the PCSAM is improved in this study by using self-stressed anti-washout concrete (SSAWC) as the filling material and by developing a lining concrete segment sleeve (LCSS) by referring to the design theory for shield lining segments. Six specimens are designed and prepared with consideration of the influential factors, such as the self-stress, thickness of the filled concrete, and concrete strength of the LCSS, then the monotonic axial compression test is carried out to investigate the improvements in the axial compression properties of the specimens. Accordingly, extended parametric analyses are performed based on the established numerical models. Finally, the calculation formula for the bearing capacity is proposed based on the analysis results. The results indicate that the SSAWC can provide initial confining compressive stress in the core region of the piers, in addition to increasing the bearing capacity and ductility of the specimens. The improved LCSS segment connection is more reliable and increases the strengthening efficiency. The influence of self-stress on the bearing capacity of the specimens is cubic and the influence of the filled concrete strength on the bearing capacity of the specimens is nonlinear. The calculation formula for predicting the bearing capacity of axially compressed columns possesses good applicability and can be used as a reference for practical engineering.

9.
Eur J Neurosci ; 2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34755396

RESUMO

The reduced density of cardiac autonomic nerves plays an important role in malignant arrhythmia after myocardial infarction (MI). Previous studies have shown that there is an interaction between the brain and the heart, and fastigial nucleus electrostimulation (FNS) promotes central nerve regeneration. Whether and how it can promote cardiac nerve regeneration after MI and the underlying mechanisms remain unknown. This study investigated whether FNS promotes cardiac nerve regeneration and reduces malignant arrhythmia inducibility in a post-infarction rat model. Ninety-eight Wistar rats were randomly assigned to Sham control, MI (left anterior descending coronary artery ligation without FNS), FNS (MI plus FNS), and FNL (fastigial nucleus lesion plus FNS plus MI) groups. The frequency of malignant arrhythmia was significantly lower in the FNS group than in the MI and FNL groups. The density of cardiac autonomic nerves was less in the MI group than in the Sham group, which was promoted by FNS. The nerve growth factor (NGF) mRNA expression was downregulated in the MI group compared to the Sham group, which was significantly enhanced by FNS. The expression levels of norepinephrine (NE) and acetylcholine (ACh) were higher and lower respectively in the MI and FNL groups than in the Sham group. After FNS, NE concentration was reduced and Ach level was elevated compared to the MI group. These data suggested that FNS promoted the regeneration of cardiac autonomic nerves and reduced the incidence of malignant arrhythmias in MI rat model. The mechanisms might involve up-regulation of NGF mRNA expression, decrease of NE release and increase of ACh release.

10.
J Org Chem ; 2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34761939

RESUMO

An efficacious method in which BINOL-type chiral imidodiphosphoric acid catalyzed the asymmetric [5 + 1] annulation reaction of 2-pyrrolylphenol with 1-methylindoline-2,3-dione was established. The strategy tolerated a broad substrate scope, and 30 examples were obtained. A range of enantioenriched spiro[3,2'-morpholine-oxindole] derivatives which incorporate a tertiary stereocenter, with moderate to excellent yields (up to 96%) and enantioselectivities (up to 99%) under mild conditions, was delivered.

11.
Opt Lett ; 46(21): 5308-5311, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34724462

RESUMO

We propose a new, to the best of our knowledge, technique to capture single particles in real-time in a microfluidic system with controlled flow using micro-pillar traps fabricated by one-step. The micro pillars are fabricated in parallel by femtosecond multi-foci laser beams, which are generated by multiplexing gratings. As the generation process does not need integration loops, the pattern and the intensity distribution of the foci array can be controlled in real-time by changing the parameters of gratings. The real-time control of the foci array enables rapidly fabricating microtraps in the microchannel with adjustment of the pillar spaces and patterns according to the sizes and shapes of target particles. This technology provides an important step towards using platforms based on single-particle analysis, and it paves the way for the development of innovative microfluidic devices for single-cell analysis.

12.
Br J Cancer ; 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34725458

RESUMO

BACKGROUND: T cell immunoglobulin and mucin domain-containing protein 3 (TIM3) is a crucial immune checkpoint and is considered as an emerging target for cancer treatment. However, the clinical significance and immune-related role of TIM3+ cells in gastric cancer remain unknown. This study aimed to investigate the clinical significance of tumour-infiltrating TIM3+ cells and their association with immune contexture in gastric cancer. METHODS: This study enrolled three cohorts, including 436 tumour tissue microarray specimens and 58 fresh tumour tissues of gastric cancer patients from Zhongshan Hospital, and 330 transcriptional data from The Cancer Genome Atlas. TIM3+ cells and their association with CD8+ T cells were evaluated by immunohistochemistry and flow cytometry analyses. Kaplan-Meier curves, Cox model and interaction test were performed to assess clinical outcomes. RESULTS: Tumour-infiltrating TIM3+ cells' high subgroups experienced poorer overall survival and disease-free survival and predicted inferior therapeutic responsiveness to fluorouracil-based adjuvant chemotherapy. TIM3 indicated CD8+ T cell dysfunction, which impeded chemotherapeutic responsiveness. Besides, HAVCR2 messenger RNA expression was associated with specific molecular characteristics. CONCLUSIONS: The abundance of tumour-infiltrating TIM3+ cells could identify an immunoevasive subtype gastric cancer with CD8+ T cell dysfunction, suggesting that TIM3 might serve as a promising target for immunotherapy in gastric cancer.

13.
Chem Sci ; 12(42): 14121-14125, 2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34760196

RESUMO

The construction of C(sp2)-X (X = B, N, O, Si, P, S, Se, etc.) bonds has drawn growing attention since heteroatomic compounds play a prominent role from biological to pharmaceutical sciences. The current study demonstrates the C(sp2)-S/Se and C(sp2)-N bond formation of one carbon of isocyanides with thiophenols or disulfides or diselenides and azazoles simultaneously. The reported findings could provide access to novel multiple isothioureas, especially hitherto rarely reported selenoureas. The protocol showed good atom-economy and step-economy with only hydrogen evolution and theoretical calculations accounted for the stereoselectivity of the products. Importantly, the electrochemical reaction could exclusively occur at the isocyano part regardless of the presence of susceptible radical acceptors, such as a broad range of arenes and alkynyl moieties, even alkenyl moieties.

14.
Sci Rep ; 11(1): 21743, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34741082

RESUMO

There is no specific treatment for pyrrolizidine alkaloid-induced hepatic sinusoidal obstruction syndrome (PA-HSOS). It is not clear when transjugular intrahepatic portosystemic shunt (TIPS) should be implemented in PA-HSOS patients. This study aimed to evaluate the timing of TIPS using total bilirubin (TBIL) as a measure, and to investigate efficacy of TIPS. We retrospectively analyzed the medical records of 10 PA-HSOS patients, among whom 4 patients had received TIPS (TIPS group), and the remaining patients were assigned to the internal medicine group. In the TIPS group, the TBIL level before TIPS was 84.4 ± 45.2 µmol/L (> 3 mg/dL), and TBIL levels were increased to different degrees after TIPS. With the extension of time, serum TBIL levels gradually decreased, and no liver failure occurred. With regards to the short-term outcomes, 3 patients recovered, 1 developed chronic illness and 0 died in the TIPS group. Moreover, 0 patients recovered, 5 developed chronic illness and 1 died in the internal medicine group. The rank sum test of group design revealed significant differences in clinical outcomes (P = 0.02). It was suggested that when the internal medicine effect of PA-HSOS patients is poor, TIPS should be considered, which is no trestricted to the limit of 3 mg/dL TBIL. It was also found TIPS effectively promote the recovery of liver function and reduce the occurrence of chronicity.

15.
J Hazard Mater ; : 127641, 2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34742611

RESUMO

Among all homogeneous catalysts, cobalt ions show the highest catalytic performance for the activation of peroxymonosulfate (PMS). Herein, we report a Co2+/PMS/H3BO3 system that can effectively generate reactive oxygen species (ROS) with ultra-low Co2+ dosage (5 µg/L). Co2+/PMS/H3BO3 system showed ultrafast reactivity and wide applicability for various pollutants. Sulfamethoxazole (SMX, 2 mg/L) could be completely removed within 5 min, and the corresponding kobs reached up to 1.1239 min-1. The introduction of H3BO3 significantly promoted the generation of ROS. The turnover frequency (TOF) calculated through dividing kobs by the cobalt ions concentration is as high as 224.78 min-1, which is much higher than most of the current research. Through a series of theoretical and experimental analyses, the complex of H2BO3--MS (HSO5B(OH)3-) was inferred to be the key substance that led to the excellent performance of the system. This work provides new insights into the Co2+/PMS system in the presence of borate buffer.

16.
Dis Markers ; 2021: 8554844, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34737838

RESUMO

Fumarate hydratase (FH) is an important enzymatic component in the tricarboxylic acid cycle. Studies have reported that FH plays an important role in hereditary leiomyomatosis and renal cell cancer (HLRCC). However, the role of FH in human different cancers remains unknown. This study is aimed at analyzing the prognostic value of FH and demonstrating the correlation between FH expression and tumor immunity. Results showed that FH was mutated or copy number varied in 27 types of cancer. FH mRNA was abnormally upregulated across various cancers. Survival analysis suggested high expression of FH was associated with poor prognosis in many cancer types, including lung adenocarcinoma (LUAD). Additionally, FH expression was associated with immune infiltration, including B cells, CD4+ T cells, CD8+ T cells, neutrophils, macrophages, and dendritic cells, especially in liver hepatocellular carcinoma (LIHC), LUAD, and lung squamous cell carcinoma (LUSC). Moreover, FH expression showed a strong correlation with immune checkpoint markers in LUAD and testicular germ cell tumors (TGCT). These results indicate that FH is an immunotherapeutic target and a potential prognostic biomarker in LUAD.

17.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 38(12): 1180-1184, 2021 Dec 10.
Artigo em Chinês | MEDLINE | ID: mdl-34839502

RESUMO

OBJECTIVE: Patients with 22q11.2 microduplications have highly variable clinical phenotypes. The clinical manifestations and prognosis of 19 fetuses carrying 22q11.2 microduplications were analyzed. METHODS: The fetuses were analyzed by single nucleotide polymorphism array (SNP array), which was followed by parental validation. Pregnancy outcome and clinical features of the newborns were analyzed in order to delineate genotype-phenotype correlation. RESULTS: Two fetuses were identified by karyotyping analysis of amniotic fluid samples. SNP array revealed that all have carried a 468.8 kb~3.4 Mb duplication in 22q11.2 region. Two couples have refused parental verification. Seven cases were inherited from the mother, 6 were from the father, and 4 cases were de novo in origin. Three couples opted termination of the pregnancy. One fetus perished at birth. Five newborns showed delayed growth, the remaining 10 were normal. CONCLUSION: The prenatal phenotype of fetuses carrying 22q11.2 microduplications are nonspecific, and the phenotypes of survivors may become more diverse along with increased age. Professional evaluation and long-term follow-up should be recommended.


Assuntos
Aconselhamento Genético , Diagnóstico Pré-Natal , Feminino , Feto , Humanos , Recém-Nascido , Cariotipagem , Fenótipo , Gravidez
18.
Sheng Wu Gong Cheng Xue Bao ; 37(11): 4066-4074, 2021 Nov 25.
Artigo em Chinês | MEDLINE | ID: mdl-34841806

RESUMO

Different fragments of SARS-CoV-2 nucleocapsid (N) protein were expressed and purified, and a fluorescence immunochromatography method for detection of SARS-CoV-2 total antibody was established. The effect of different protein fragments on the performance of the method was evaluated. The N protein sequence was analyzed by bioinformatics technology, expressed in prokaryotic cell and purified by metal ion affinity chromatography column. Different N protein fragments were prepared for comparison. EDC reaction was used to label fluorescence microsphere on the synthesized antigen to construct sandwich fluorescence chromatography antibody detection assay, and the performance was systemically evaluated. Among the 4 prepared N protein fragments, the full-length N protein (N419) was selected as the optimized coating antigen, N412 with 0.5 mol/L NaCl was used as the optimal combination; deleting 91-120 amino acids from the N-terminal of N412 reduced non-specific signal by 87.5%. the linear range of detection was 0.312-80 U/L, the limit of detection was 0.165 U/L, and the accuracy was more than 95%. A fluorescence immunochromatographic detection method for analysis of SARS-CoV-2 total antibody was established by pairing N protein fragments. The detection result achieved 98% concordance with the commercially available Guangzhou Wanfu test strip, which is expected to be used as a supplementary approach for detection of SARS-CoV-2. The assay could also provide experimental reference for improving the performance of COVID-19 antibody detection reagents.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Antivirais , Cromatografia de Afinidade , Imunofluorescência , Humanos , Microesferas , Sensibilidade e Especificidade
19.
Mater Horiz ; 8(5): 1488-1498, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34846457

RESUMO

Continuous real-time measurement of body temperature using a wearable sensor is an essential part of human health monitoring. Electrospun aligned carbon nanofiber (ACNF) films are employed to assemble flexible temperature sensors. The temperature sensor prepared at a low carbonization temperature of 650 °C yields an outstanding sensitivity of 1.52% °C-1, high accuracy, good linearity, fast response time and excellent long-term durability. Moreover, it exhibits high discriminability towards temperature amidst other unwanted stimuli and maintains its original performance even after repeated stretch/release cycles because of highly-aligned structures. The correlation between the atomic structure and the temperature sensing performance of ACNF sensors is established. Contrary to conventional highly conductive temperature sensors, the ACNF sensor with a low electrical conductivity prepared at a low carbonization temperature ameliorates the temperature sensing performance. This anomaly is explained by (i) the smaller and more disordered sp2 carbon crystallites yielding a high negative temperature coefficient, (ii) a larger number of defects, and (iii) a higher pyridinic-N content generating abundant entrapped and localized electrons which are activated once sufficient thermal energy is available. Flexible ACNF sensor's overall performance is among the best-known carbon material-based flexible temperature sensors, demonstrating potential applications in emerging healthcare and flexible electronics technologies.

20.
Nano Lett ; 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34846904

RESUMO

Biomineralization generates hierarchically structured minerals with vital biological functions in organisms. This strategy has been adopted to construct complex architectures to achieve similar functionalities, mostly under chemical environments mimicking biological components. The molecular origin of the biofacilitated mineralization process is elusive. Herein, we describe the mineralization of hydroxyapatite (HAp) accompanying the biological secretion of nanocellulose by Acetobacter xylinum. In comparison with mature cellulose, the newly biosynthesized cellulose molecules greatly accelerate the nucleation rate and facilitate the uniform distribution of HAp crystals, thereby generating composites with a higher Young modulus. Both simulations and experiments indicate that the biological metabolism condition allows the easier capture of calcium ions by the more abundant hydroxyl groups on the glucan chain before the formation of hydrogen bonding, for the subsequent growth of HAp crystals. Our work provides more insights into the biologically accelerated mineralization process and presents a different methodology for the generation of biomimetic nanocomposites.

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