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In this paper, we consider a (ϕ 1 , ϕ 2) -Laplacian system as follows: { Δ ϕ 1 (Δ u (t − 1)) + ∇ u F (t , u (t) , v (t)) = 0 , Δ ϕ 2 (Δ v (t − 1)) + ∇ v F (t , u (t) , v (t)) = 0 , where F (t , u (t) , v (t)) = − K (t , u (t) , v (t)) + W (t , u (t) , v (t)) is T-periodic in t. By using the mountain pass theorem, we obtain that the (ϕ 1 , ϕ 2) -Laplacian system has at least one periodic solution if W is asymptotically (p , q) -linear at infinity. Our results improve and extend some known works. [ABSTRACT FROM AUTHOR]

It is known that image priors are essential to blind deconvolution. Reweighted graph total variation (RGTV), as a new prior to substitute the most classical total variation (TV), has been shown superior to TV and several other cutting-edge models both theoretically and empirically. This paper steps forward, firstly providing a simpler geometric perspective to RGTV in the framework of variational partial differential equations (PDEs), rather than the previous graph spectral interpretation made in the graph frequency domain. Surprisingly, a slight shift of perspective as such finally leads to a huge blind deblurring performance boosting in both accuracy and efficiency as compared to the previously derived numerical approach, which approximates RGTV as the graph L1-Laplacian regularizer. Utilizing the simplified RGTV as reformulated in this paper, another valuable contribution is an exploration of its potentials for blind facial image restoration by combining unsupervised deep facial models. Experimental results of blind face deblurring and blind face hallucination both demonstrate necessity and rationale of a joint model-based and learning-based approach to blind face restoration. [ABSTRACT FROM AUTHOR]

Transparent conductive films that are based on nanowire networks are essential to construct flexible, wearable, and even stretchable electronics. However, large-scale precise micropatterning, especially with regard to the controllability of the organizing orientation of nanowires, is a critical challenge. Herein, we proposed a liquid film rupture self-assembly approach for manufacturing transparent conductive films with microstructure arrays based on a highly ordered nanowire network. The large-scale microstructure conductive films were fabricated through air–liquid interface self-assembly and liquid film rupture self-assembly. Six typical micropattern morphologies, including square, hexagon, circle, serpentine, etc., were prepared to reveal the universal applicability of the proposed approach. The homogeneity and controllability of this approach were verified for multiple assemblies. With the assembly cycles increasing, the optical transmittance decreases slightly. In addition, theoretical model analysis is carried out, and the analytical formula of the speed of the film moving with the surface tension and the density of the liquid film is presented. Finally, the feasibility of this approach for piezoresistive strain sensors is verified. This fabrication approach demonstrated a cost-effective and efficient method for precisely arranging nanowires, which is useful in transparent and wearable applications. [ABSTRACT FROM AUTHOR]

In recent years, deep learning-based methods have been extensively developed to diagnose Prostate Cancer (PCa) with bi-parametric Magnetic Resonance Imaging (bpMRI) images. Due to the vague characteristic of PCa bpMRI images, the spacial lesion annotations and grading annotations inevitably contain some noises, which has a serious impact on the performance of deep learning models for the diagnosis of PCa. Furthermore, the similar background features of PCa bpMRI image also disturb the prediction performance of deep learning models. In this paper, we propose a two-branch Noise-Resistant Distillation Network (NRD-Net) for the accurate diagnosis of PCa with bpMRI images. Firstly, the influence of irrelevant background on the classification can be reduced by segmenting the labeled constrained classification response maps. Then a novel confidence-based binarization segmentation scheme and a multi-branch online distillation classification scheme are proposed to reduce the spatial and grading noises simultaneously. Extensive experiments are conducted on a private dataset and the public PROSTATEx-2 dataset. For the private dataset, the proposed network obtains the best performance for GG prediction, achieving a mean quadratic weighted Kappa of 0.5115 and a mean positive predictive value (PPV) of 0.9506. For the public dataset, the proposed method achieves state-of-the-art results of 0.5058 Kappa and 0.9473 PPV. [ABSTRACT FROM AUTHOR]

In order to reduce the influence of temperature on the operating performance of the macro and micro drive, a double-wounding circulating water cooling structure is proposed. Based on the law of thermal resistance, the heat transfer model of the macro and micro drive forced convec-tion cooling was established, and the influencing factors of the internal temperature distribution of the macro and micro drive system were analyzed. And the macro to micro drive forced con-vection cooling when the macro dynamic system part of the output force, and the size of the output displacement and micro system of the rise of temperature of the giant magnetostrictive material (GMM) and output displacement simulation and experiment, the results show that when the circulating water flow rate is more than 3 m/s, macro to micro drive internal temperature decreased significantly, the macro dynamic range at around 1 N. The fluctuation range of macrodynamic output displacement is between 0∼20 µm. The error of output displacement gen-erated by the micro-motion magnetostrictive rod is less than 1 µm, at this time, the temperature change has little influence on the output force, output displacement and micro output displace-ment of the macro-moving part. [ABSTRACT FROM AUTHOR]

Wireless sensor network nodes are widely used in wearable devices, consumer electronics, and industrial electronics and are a crucial component of the Internet of Things (IoT). Recently, advanced power technology with sustainable energy supply and pollution-free characteristics has become a popular research focus. Herein, to realize an unattended and reliable power supply unit suitable for distributed IoT systems, we develop a high-performance triboelectric-electromagnetic hybrid nanogenerator (TEHNG) to harvest mechanical energy. The TEHNG achieves a high load power of 21.8 mW by implementing improvements of material optimization, configuration optimization and pyramid microstructure design. To realize a self-powered integrated microsystem, a power management module, energy storage module, sensing signal processing module, and microcontroller unit are integrated into the TEHNG. Furthermore, an all-in-one wireless multisensing microsystem comprising the TEHNG, the abovementioned integrated functional circuit and three sensors (temperature, pressure, and ultraviolet) is built. The milliwatt microsystem operates continuously with the TEHNG as the only power supply, achieving self-powered operations of sensing environmental variables and transmitting wireless data to a terminal in real time. This shows tremendous application potential in the IoT field. [ABSTRACT FROM AUTHOR]

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As one of the promising human—machine interfaces, wearable sensors play an important role in modern society, which advances the development of wearable fields, especially in the promising applications of electronic skin (e-skin), robotics, prosthetics, and healthcare. In the last decades, wearable sensors tend to be capable of attractive capabilities such as miniaturization, multifunction, and smart integration, and wearable properties such as lightweight, flexibility, stretchability, and conformability for wider applications. In this work, we developed a stretchable multifunctional sensor based on porous silver nanowire/silicone rubber conductive film (P-AgNW/SR). Its unique structural configuration, i.e., an assembly of the P-AgNW/SR with good conductivity, stability, and resistance response, and the insulated silicone rubber layer, provided the feasibility for realizing multiple sensing capabilities. Specifically, porous microstructures of the P-AgNW/SR made the device to be used for pressure sensing, exhibiting outstanding dynamic and static resistive responsive behaviors and having a maximum sensitivity of 9.062 %·N−1 in a continuous compressive force range of ∼ 16 N. With the merit of the good piezoresistive property of AgNW/SR networks embedded into the surface of micropores of the P-AgNW/SR, the device was verified to be a temperature sensor for detecting temperature changes in the human body and environment. The temperature sensor had good sensitivity of 0.844 %·°C−1, high linearity of 0.999 in the range of 25–125 °C, and remarkable dynamic stability. Besides, the developed sensor was demonstrated to be a single electrode-triboelectric sensor for active sensing, owing to the unique assembly of the conductive P-AgNW/SR electrode and the silicone rubber friction layer. Based on the coupling effect of the triboelectrification and electrostatic induction, the generated electrical signals could be used to sense the human motions, according to the quantitative correlation between the human motions and the features in amplitude and waveform of the output signals. Thus, the developed stretchable sensor successfully achieved the integration of two types of passive sensing capabilities, i.e., pressure and temperature sensing, and one type of active sensing capability, i.e., triboelectric sensing, demonstrating the feasibility of monitoring multiple variables of the human body and environment. [ABSTRACT FROM AUTHOR]

Blind deblurring has undergone rapid development since the variational Bayes method of Fergus et al. about 15 years ago. Nowadays, it is generally acknowledged in the statistical view that unnatural heavy-tailed image priors should be advocated for blind deblurring. However, this paper affirms that an image prior driven by the dual principles of discriminativeness is indeed more critical and essential to blind deblurring, inspired by which a new type of reweighted Tikohonov image regularization is formulated. In comparison with previous approaches, the model in this paper is not only more concise in mathematics but also more intuitive in understanding. Experimenting within a plug-and-play numerical framework on images of natural, manmade, low-illumination, text, and people classes well validate the effectiveness and robustness of the proposed model. More importantly, its practicality to realistic challenging deblurring problems is also demonstrated. In the final, it is believed that this paper could break a long-standing prejudice on maximum-a-posterior-based blind deblurring, i.e., various modeling tricks should be developed to ensure top performance of blind deblurring. However, this paper states that the problem can be formulated in a more strict modeling fashion, just similar to the non-blind deblurring task in a great sense. [ABSTRACT FROM AUTHOR]

In this paper, a class of nonlinear ψ-Hilfer fractional integrodifferential coupled systems on a bounded domain is investigated. The existence and uniqueness results for the coupled systems are proved based on the contraction mapping principle. Moreover, the Ulam–Hyers–Rassias, Ulam–Hyers, and semi-Ulam–Hyers–Rassias stabilities to the initial value problem are obtained. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Central South University is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Titanium mesh exposure after cranioplasty is a possible complication and is usually managed by mesh removal and flap transfer, but the advantages of the rigid prosthesis are then lost. This study aimed to present our experience with negative pressure wound therapy combined with soft tissue dilation for retaining the titanium mesh in patients with mesh exposure after cranioplasty. Methods: This retrospective study included patients treated between 01/2016 and 05/2019 at the Jiangyin Hospital Affiliated to Southeast University School of Medicine. The wound was cleaned, and a cystic space was created for the tissue dilator, which was used with a self-designed negative pressure dressing. After the target dilation was achieved, the repair was conducted while retaining the titanium mesh. Results: Eight patients were included (seven males and one female; 53.6 ± 8.8 (range, 43–65) years of age). The exposed mesh area ranged from 1 × 1 to 4 × 5.5 cm. The thinning scalp area around the exposed mesh ranged from 3.6 × 3.8 to 4 × 5.5 cm. Five patients had positive wound cultures and received sensitive antibiotics. The dilator embedding time was 20–28 days. The time of negative pressure wound therapy was 25–33 days. The hospital stay was 30–41 days. Primary wound healing was achieved in all eight patients. There were no signs of recurrence after 6–18 months of follow-up. The cranial CT scans were unremarkable. Conclusions: Negative pressure wound therapy combined with soft tissue dilation for exposed titanium mesh after cranioplasty might help retain the titanium mesh. [ABSTRACT FROM AUTHOR]

Wearable electronics, as essential components of the Internet of Things (IoT), have attracted widespread attention, and the trend is to configure attractive wearable smart microsystems by integrating sensing, powering, and other functions. Herein, we developed an elastic hybrid triboelectric–electromagnetic microenergy harvester (named EHTE) to realize hybrid sensing and microenergy simultaneously. This EHTE is a highly integrated triboelectric nanogenerator (TENG) and electromagnetic nanogenerator (EMG). Based on the triboelectric–electromagnetic hybrid mechanism, an enhanced electrical output of the EHTE was achieved successfully, which demonstrates the feasibility of the EHTE for microelectronics powering. Moreover, with the merits of the EMG, the developed hybrid microenergy harvester integrated both active frequency sensing and passive inductive sensing capabilities. Specifically, the almost linear correlation of the electromagnetic outputs to the frequencies of the external stimulus endowed the proposed EHTE with an outstanding active frequency sensing ability. In addition, due to the unique structural configuration of the EMG (i.e., a conductive permanent magnet (PM), hybrid deformation layer, and flexible printed circuit board (FPCB) coil), an opportunity was provided for the developed EHTE to serve as a passive inductive sensor based on the eddy current effect (i.e., a form of electromagnetic induction). Therefore, the developed EHTE successfully achieved the integration of hybrid sensing (i.e., active frequency sensing and passive inductive sensing) and microenergy (i.e., the combination of electromagnetic effect and triboelectric effect) within a single device, which demonstrates the potential of this newly developed EHTE for wearable electronic applications, especially in applications of compact active microsystems. [ABSTRACT FROM AUTHOR]

Non-Ribosomal Peptide Synthetases (NRPSs) assemble a diverse range of natural products with important applications in both medicine and agriculture. They consist of several multienzyme subunits that must interact with each other in a highly controlled manner to facilitate efficient chain transfer, thus ensuring biosynthetic fidelity. Several mechanisms for chain transfer are known for NRPSs, promoting structural diversity. Herein, we report the first biochemically characterized example of a type II thioesterase (TEII) domain capable of catalysing aminoacyl chain transfer between thiolation (T) domains on two separate NRPS subunits responsible for installation of a dehydrobutyrine moiety. Biochemical dissection of this process reveals the central role of the TEII-catalysed chain translocation event and expands the enzymatic scope of TEII domains beyond canonical (amino)acyl chain hydrolysis. The apparent co-evolution of the TEII domain with the NRPS subunits highlights a unique feature of this enzymatic cassette, which will undoubtedly find utility in biosynthetic engineering efforts. Non-Ribosomal Peptide Synthetases (NRPSs) are responsible for the construction of many types of natural products. Here the authors characterize a key type II thioesterase domain that sheds light on the chain translocation processes of legonmycin NRPSs. [ABSTRACT FROM AUTHOR]

Ribosomally synthesized and post-translationally modified peptides (RiPPs) are structurally complex natural products with diverse bioactivities. Here we report discovery of a RiPP, kintamdin, for which the structure is determined through spectroscopy, spectrometry and genomic analysis to feature a bis-thioether macrocyclic ring and a β-enamino acid residue. Biosynthetic investigation demonstrated that its pathway relies on four dedicated proteins: phosphotransferase KinD, Lyase KinC, kinase homolog KinH and flavoprotein KinI, which share low homologues to enzymes known in other RiPP biosynthesis. During the posttranslational modifications, KinCD is responsible for the formation of the characteristic dehydroamino acid residues including the β-enamino acid residue, followed by oxidative decarboxylation on the C-terminal Cys and subsequent cyclization to provide the bis-thioether ring moiety mediated by coordinated action of KinH and KinI. Finally, conserved genomic investigation allows further identification of two kintamdin-like peptides among the kin-like BGCs, suggesting the occurrence of RiPPs from actinobacteria. The chemical diversity of peptides from ribosomal origin is a growing field of research. Here, the authors report the discovery, genomic and biosynthetic investigations of kintamdin, a ribosomally synthesized and post-translationally modified peptides featuring a beta-enamino acid and a bis-thioether macrocyclic motif. [ABSTRACT FROM AUTHOR]

Antistatic and strength properties are of vital importance for polyurethane rubber used in moving parts of many industrial instruments. Herein, polyurethane was composited with polyaniline and nanosilica based on in situ synthesis of polymer and physical mixing of these fillers to reach desired antistatic and mechanical properties. Chemical, morphological and thermal properties of the polyurethane/polyaniline/nanosilica composites were studied. The electrical resistivity of the composite decreased from 1.1×106 MΩ to 7.6×104 MΩ as a result of the addition of 4% polyaniline. The tensile strength and elongation at break of the polyurethane composites improved by nearly 300% and 100%, respectively, when compared with those of the neat polyurethane. The electronic resistance of PU/PANI/NS ternary is low enough for its antistatic property and decreases with the increase of the added nanosilica, which is unexpectedly and rather significant. Our results would shed light on the development of antistatic PU with excellent mechanical performance. [ABSTRACT FROM AUTHOR]

Hyperglycemia aggravates cerebral ischemia/reperfusion (I/R) injury via vascular injury. There is still a lack of effective pharmaceutical preparations for cerebral I/R injury under hyperglycemia. This study aimed to investigate the effects of oxymatrine (OMT) on hyperglycemia-exacerbated cerebral I/R injury in vitro and in vivo. The middle cerebral artery occlusion (MCAO) and reperfusion was established in the rats under hyperglycemia. Meanwhile, oxygen–glucose deprivation and reoxygenation (OGD/R) with high glucose was used as an in vitro model of hyperglycemic cerebral I/R injury. The results showed that the neurological deficit score, mortality, infarct volume and penumbra apoptosis in hyperglycemia group were significantly higher than those in normal glucose group. OMT pre-treated obviously reduced the degree of neurological deficit, mortality, infarct volume, improve cerebral blood flow after I/R in rats with hyperglycemia, and increase the survival rate of human brain microvascular endothelial cells (HBMECs) in high glucose and OGD/R group. OMT significantly improved the ultrastructure changes of endothelial cells, and maintain the migration and angiogenesis potency of HBMECs in high glucose and OGD/R group. OMT obviously alleviated the down-regulating CD31 and CD105 expression in cerebral microvessels caused by hyperglycemia. It is concluded that OMT treatment might alleviate cerebral I/R injury under hyperglycemia via protecting microvessels. [ABSTRACT FROM AUTHOR]

Purpose: This aim of this study was to investigate the association of physical activity with OSA risk among adult Chinese. Methods: Participants were selected from baseline survey of the Guangzhou Heart Study. OSA was ascertained by using Berlin Questionnaire, and the physical activity, including leisure-time physical activity (LTPA), occupational activity, and transport activity, was measured with modified Global Physical Activity Questionnaire. Principal component analysis was used to extract the patterns of LTPA with varimax orthogonal transformation. Odds ratios (OR) with 95% confidence interval (95% CI) were calculated by using the logistic regression method. Results: For all 9733 participants, aged 35 to 74 years, LTPA (high vs. inactive, OR: 0.81, 95% CI: 0.64–1.03), occupational activity (vigorous vs. retirement, OR:1.28, 95% CI: 0.93–1.75) and transport activity (high vs. retirement, OR: 1.05, 95% CI: 0.69–1.60) were not associated with OSA risk after considering potential confounders. Any specific component of LTPA and two LTPA patterns were also not associated with OSA risk. Stratified analysis yielded similar nonsignificant association of OSA risk with three dimensions of physical activity in both the retirement group and non-retirement group. Conclusion: This study found that three dimensions of physical activity, including LTPA, transport activity, and occupational activity, were not associated with any risk of OSA. Future studies with longitudinal design are needed. [ABSTRACT FROM AUTHOR]

Traffic sign detection (TSD) using convolutional neural networks (CNN) is promising and intriguing for autonomous driving. Especially, with sophisticated large-scale CNN models, TSD can be performed with high accuracy. However, the conventional CNN models suffer the drawbacks of being time-consuming and resource-hungry, which limit their application and deployments in various platforms of limited resources. In this paper, we propose a novel real-time traffic sign detection system with a lightweight backbone network named Depth Separable DetNet (DS-DetNet) and a lite fusion feature pyramid network (LFFPN) for efficient feature fusion. The new model can achieve a performance trade-off between speed and accuracy using a depthwise separable bottleneck block, a lite fusion module, and an improved SSD detection front-end. The testing results on the MS COCO and the GTSDB datasets reveal that 23.1% mAP with 6.39 M parameters and only 1.08B FLOPs on MSCOCO, 81.35% mAP with 5.78 M parameters on GTSDB. With our model, the run speed is 61 frames per second (fps) on GTX 1080ti, 12 fps on Nvidia Jetson Nano and 16 fps on Nvidia Jetson Xavier NX. [ABSTRACT FROM AUTHOR]

Nitrogen retention within a watershed reduces the amount of N exported to the ocean; however, it worsens environmental problems, including surface water eutrophication, aquifer pollution, acid rain, and soil acidification. Here, we adopted the Soil and Water Assessment Tool (SWAT) model to describe the riverine N output and retention effects in the Shanmei Reservoir Basin, a subtropical mountainous basin located in Quanzhou City, Southeast China. The results revealed that farmlands and orchards in the upstream and central parts of the basin were the dominant land use types, which contributed large N yields. Fertilizer application was the key source of riverine N output and N retention within the basin. On average, approximately 64% of anthropogenic N inputs were retained within the basin, whereas 36% of total N was exported to the downstream and coastal areas. The average N retention efficiency was 80% in a dry year, and within the year, N retention occurred in spring and summer and N release occurred in autumn and winter. The annual variation in N retention within the basin was largely dominated by changes in rainfall and runoff, whereas the seasonal characteristics of N retention were mainly affected by fertilization. Even with a large decrease in fertilizer application, owing to the contributions of the residual N pool and river background, the riverine N output still maintained a certain base value. The effects of precipitation, land use types, and agricultural fertilizer on N retention should be comprehensively considered to implement reasonable N management measures. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Central South University is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the progress of speech retrieval technology in the cloud, it brings a lot of conveniences for speech user. Yet, the inquiry encrypted speech results from the speech retrieval system are faced with some secure issues to settle, such as integrity authentication and tampering recovery. In this paper, an encrypted speech authentication and tampering recovery method based on perceptual hashing is proposed. Firstly, the original speech is scrambled by Duffing mapping to construct an encrypted speech library in the cloud, through extracting product of uniform sub-band spectrum variance and spectral entropy of encrypted speech and constructing a perceptual hashing sequence to generate the hashing template of the cloud. From this, a one-to-one correspondence between the encrypted speech and perceptual hashing sequence is established. Secondly, the authentication digest of encrypted speech is extracted according to the inquiry result during the retrieval. Then, the authentication digest and the perceptual hashing sequence of the hashing template in the cloud are matched by the Hamming distance algorithm. Finally, for encrypted speech that fails authentication, tampering detection and location are performed, and the tampered samples are recovered by the least square curve fitting method. The simulation results show that the proposed method can extract the authentication digest directly in the encrypted speech, and the authentication digest not only has good discrimination and robustness, but it accurately locates the tampered area for malicious substitution and mute attacks. In addition, the proposed method can recover tampered speech signals in high quality without any extra information. [ABSTRACT FROM AUTHOR]

The introduction of β-hydroxy-α-amino acids (βHAAs) into organic molecules has received considerable attention as these molecules have often found widespread applications in bioorganic chemistry, medicinal chemistry and biomaterial science. Despite innovation of asymmetric synthesis of βHAAs, stereoselective synthesis to control the two chiral centres at Cα and Cβ positions is still challenging, with poor atomic economy and multi protection and deprotection steps. These syntheses are often operated under harsh conditions. Therefore, a biotransformation approach using biocatalysts is needed to selectively introduce these two chiral centres into structurally diverse molecules. Yet, there are few ways that enable one-step synthesis of βHAAs. One is to extend the substrate scope of the existing enzyme inventory. Threonine aldolases have been explored to produce βHAAs. However, the enzymes have poor controlled installation at Cβ position, often resulting in a mixture of diastereoisomers which are difficult to be separated. In this respect, l-threonine transaldolases (LTTAs) offer an excellent potential as the enzymes often provide controlled stereochemistry at Cα and Cβ positions. Another is to mine LTTA homologues and engineer the enzymes using directed evolution with the aim of finding engineered biocatalysts to accept broad substrates with enhanced conversion and stereoselectivity. Here, we review the development of LTTAs that incorporate various aldehyde acceptors to generate structurally diverse βHAAs and highlight areas for future developments. Key points: • The general mechanism of the transaldolation reaction catalysed by LTTAs • Recent advances in LTTAs from different biosynthetic pathways • Applications of LTTAs as biocatalysts for production of βHAAs [ABSTRACT FROM AUTHOR]

It is important to evaluate the durability of the protective immune response elicited by primary infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Here, we systematically evaluated the SARS-CoV-2-specific memory B cell and T cell responses in healthy controls and individuals recovered from asymptomatic or symptomatic infection approximately 6 months prior. Comparatively low frequencies of memory B cells specific for the receptor-binding domain (RBD) of spike glycoprotein (S) persisted in the peripheral blood of individuals who recovered from infection (median 0.62%, interquartile range 0.48-0.69). The SARS-CoV-2 RBD-specific memory B cell response was detected in 2 of 13 individuals who recovered from asymptomatic infection and 10 of 20 individuals who recovered from symptomatic infection. T cell responses induced by S, membrane (M), and nucleocapsid (N) peptide libraries from SARS-CoV-2 were observed in individuals recovered from coronavirus disease 2019 (COVID-19), and cross-reactive T cell responses to SARS-CoV-2 were also detected in healthy controls. [ABSTRACT FROM AUTHOR]

Heavy metal (HM) pollution in orchards is becoming serious in many countries, and some fruit HMs exceed the safety limits. In this study, contents of 8 HMs (Cd, Hg, As, Pb, Cr, Cu, Ni, and Zn) in 5 kiwifruit orchard soils and the tissues (roots, twigs, leaves, fruits) of 4 kiwifruit varieties collected from Qianjiang district, Chongqing city, China, were determined. Seven HMs could meet priority protection class I, except for Cd with slightly poor environmental quality, including 4% and 53% of the samples belonging to the strict control class III and safe utilization class II, respectively. The potential ecological risk index (235.30) indicated that the HMs in the orchard soil were of medium potential ecological risk. The HMs' migration from rock to soil was very obvious. Kiwifruit was easy to accumulate Cu from soil and it had high Zn and Ni translocations to above-ground parts from roots. Compared with other tissues, HMs' concentrations in fruits were the lowest. From the perspective of human health, about 8.3% and 0.83% of the fruit samples for Cr and Cu exceeded the national maximum permissible levels, respectively; fortunately, the health risk index (HRI) values for all the fruit samples were within the safe limits. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Acupuncture & Tuina Science is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

β-Hydroxy-α-amino acids (βH-AAs) are key components of many bioactive molecules as well as exist as specialised metabolites. Among these βH-AAs, 4-fluorothreonine (4-FT) is the only naturally occurring fluorinated AA discovered thus far. Here we report overexpression and biochemical characterisation of 4-fluorothreonine transaldolase from Streptomyces sp. MA37 (FTaseMA), a homologue of FTase previously identified in the biosynthesis of 4-FT in S. cattleya. FTaseMA displays considerable substrate plasticity to generate 4-FT as well as other β-hydroxy-α-amino acids with various functionalities at C4 position, giving the prospect of new chemo-enzymatic applications. The enzyme has a hybrid of two catalytic domains, serine hydroxymethyltransferase (S) and aldolase (A). Site-directed mutagenesis allowed the identification of the key residues of FTases, suggesting that the active site of A domain has a historical reminiscent feature in metal-dependent aldolases. Elemental analysis demonstrated that FTaseMA is indeed a Zn2+-dependent enzyme, the first example of pyridoxal phosphate (PLP) enzyme family fused with a metal-binding domain carrying out a distinct catalytic role. Finally, FTaseMA showed divergent evolutionary origin with other PLP dependent enzymes. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effect of compound laser acupuncture-moxibustion on blood glucose, fasting insulin and blood lipids levels in type 2 diabetes mellitus (T2DM) rats. Methods: Forty male Wistar rats were randomly divided into 4 groups, including the normal group, model control group, laser group and sham laser group (n=10 per group). The rats in the normal group were fed with a standard diet. Rats in other groups were fed with a high-sugar and high-fat diet for 4 weeks, then intraperitoneally injected with 1% streptozotocin to induce T2DM model. The laser group was irradiated by 10.6 µm and 650 nm compound laser on bilateral Pishu (BL 20), Shenshu (BL 23) and Sanyinjiao (SP 6) for 5 min, 6 times a week for 5 weeks. The sham laser group received the same treatment as the laser group, but without laser output. The model control group and normal group were not treated. Blood glucose levels were measured before and after 1, 2, 3, 4 and 5 weeks of treatment. The serum levels of fasting insulin, total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL), and high-density lipoprotein (HDL) were analyzed after the last treatment. Results: The blood glucose levels in the model control group increased during the 5 weeks of treatment compared with the normal group (P<0.05), while those in the laser group were significantly lower than the model control group after weekly treatment (P<0.01 or P<0.05). After 1, 2 and 3 weeks of treatment, the blood glucose levels in the laser group decreased obviously compared with the sham laser group (P<0.01 or P<0.05). Compared with the normal group, the levels of fasting insulin, TC and LDL in the model control group notably increased (P<0.01 or P<0.05), while their levels in the laser group were significantly lower than the model control group after 5 weeks of treatment (P<0.05 or P<0.01). However, no statistically significant differences were observed in TG or HDL levels among the 4 groups (P>0.05). Conclusion: The compound laser acupuncture-moxibustion of 10.6 µm and 650 nm had positive effects on the regulation of hyperglycemia and insulin resistance in T2DM rats, which may be a potential treatment for T2DM, and also provide an alternative to the traditional acupuncture and moxibustion therapy. [ABSTRACT FROM AUTHOR]

Background and Objectives: MET401 is a potent and selective c-Met inhibitor with a novel triazolopyrimidine scaffold. The aim of this study was to determine the pharmacokinetic profile of MET401 in preclinical species, and to identify the metabolic soft spot and enzyme involved, in order to help medicinal chemists to modify the compound to improve the pharmacokinetic profile. Methods: A metabolite identification study was performed in different liver fractions from various species. Chemical inhibition with selective cytochrome P450 (CYP) and molybdenum hydroxylase inhibitors was carried out to identify the enzyme involved. The deuterium substitution strategy was adopted to reduce metabolism. Pharmacokinetic studies were performed in rats to confirm the effect. Results: Although M-2 is a minor metabolite in liver microsomal incubations, it became the predominant metabolite in incubations with liver S9, cytosol, hepatocytes and rat pharmacokinetic study. M-2 was synthesized enzymatically and the structure was identified as a mono-oxidation on the triazolopyrimidine moiety. The M-2 formation was ascribed to aldehyde oxidase (AO)-mediated metabolism based on the following evidence—M-2 production was NADPH independent, pan-CYP inhibitor 1-aminobenzotriazole and xanthine oxidase inhibitor allopurinol did not inhibit M-2 formation, and AO inhibitors menadione and raloxifene inhibited M-2 formation. The deuterated analog MET763 demonstrated an improved pharmacokinetic profile with lower clearance, longer terminal half-life and double oral exposure compared with MET401 in rats. Conclusions: These results indicate that the main metabolic pathway of MET401 is AO-mediated metabolism, which leads to poor in vivo pharmacokinetic profiles in rodents. The deuterium substitution strategy could be used to reduce AO-mediated metabolism liability. [ABSTRACT FROM AUTHOR]

Atrial fibrillation (AF) and heart failure (HF) are two clinical entities that can present either separately or concurrently. One entity can lead to the other and vice versa as AF can not only be the underlying etiology of HF but also exacerbate HF due to other cardiac diseases. Besides prevention of cerebral and systemic embolism and elimination of AF-related symptoms, restoration of sinus rhythm for AF patients helps to avoid or reduce HF, irrespective of their underlying heart disease. Successful rates of medical therapy for AF are low in persistent AF, and much lower in long-standing AF, while invasive procedures for AF yield promising results. In this review, the authors evaluate the value of invasive therapies for HF patients complicated with non-valvular AF. We examine this clinical problem by interpreting the relationships between these two entities: the mechanism of tachycardia-induced cardiomyopathy (TIC), past opinions about rhythm control and rate control of AF, discrimination of HF-related AF and AF-induced HF, how to identify the AF patients that could benefit from invasive therapies, and how to select invasive therapies for different AF patients and peri-operative treatments. [ABSTRACT FROM AUTHOR]

In order to achieve extraction perceptual features from the encryption speech as a search digest for the content-based encryption speech retrieval, we present a retrieval algorithm of encrypted speech based on short-term cross-correlation and perceptual hashing in this paper. Firstly, the study encrypts the speech file and uploads the encrypted speech data to the encryption speech database in cloud server. Secondly, the sample speech clips are obtained by the cutting operation from the speech file for scrambling encryption. The perceptual hashing sequence of the encrypted speech is constructed by extracting the short-term cross-correlation of the encrypted speech signals as the search digest. These perceptual hashing sequences are uploaded into the hashing index table of cloud server. Finally, the Hamming distance algorithm is used for the matching retrieval operation during the search. The experimental results show that the proposed algorithm of encrypted speech perceptual hashing has a better discrimination, robustness and compactness, and the perceptual hashing sequences can be extracted directly from the encrypted sample speech. Meanwhile, the encryption speech signal has high recall and precision ratios after various content preserving operations. In the whole retrieval process, the downloading and decrypting operations of speech data are not necessary. [ABSTRACT FROM AUTHOR]

Single-image nonparametric blind super-resolution is a fundamental image restoration problem yet largely ignored in the past decades among the computational photography and computer vision communities. An interesting phenomenon is observed that learning-based single-image super-resolution (SR) has been experiencing a rapid development since the boom of the sparse representation in 2005s and especially the representation learning in 2010s, wherein the high-res image is generally blurred by a supposed bicubic or Gaussian blur kernel. However, the parametric assumption on the form of blur kernels does not hold in most practical applications because in real low-res imaging a high-res image can undergo complex blur processes, e.g., Gaussian-shaped kernels of varying sizes, ellipse-shaped kernels of varying orientations, curvilinear kernels of varying trajectories. The paper is mainly motivated by one of our previous works: Shao and Elad (in: Zhang (ed) ICIG 2015, Part III, Lecture notes in computer science, Springer, Cham, 2015). Specifically, we take one step further in this paper and present a type of adaptive heavy-tailed image priors, which result in a new regularized formulation for nonparametric blind super-resolution. The new image priors can be expressed and understood as a generalized integration of the normalized sparsity measure and relative total variation. Although it seems that the proposed priors are simple, the core merit of the priors is their practical capability for the challenging task of nonparametric blur kernel estimation for both super-resolution and deblurring. Harnessing the priors, a higher-quality intermediate high-res image becomes possible and therefore more accurate blur kernel estimation can be accomplished. A great many experiments are performed on both synthetic and real-world blurred low-res images, demonstrating the comparative or even superior performance of the proposed algorithm convincingly. Meanwhile, the proposed priors are demonstrated quite applicable to blind image deblurring which is a degenerated problem of nonparametric blind SR. [ABSTRACT FROM AUTHOR]

As inhaled anesthetics are widely used, medical staff have inevitably suffered from exposure to anesthetic waste gases (WAGs). Whether chronic exposure to WAGs has an impact on the health of medical staff has long been a common concern, but conclusions are not consistent. Many measures and equipment have been proposed to reduce the concentration of WAGs as far as possible. This review aims to dissect the current exposure to WAGs and its influence on medical staff in the workplace and the environment, and summarize strategies to reduce WAGs. [ABSTRACT FROM AUTHOR]

Cholelithiasis is a kind of common and multiple diseases. In recent years, traditional laparotomy has been challenged by a minimally invasive surgery. Through literature review, the therapeutic method, effect, and complications of minimally invasive treatment of intrahepatic and extrahepatic bile duct stones by combining our practical experience were summarized as follows. (1) For intrahepatic bile duct stones, the operation may be selected by laparoscopic liver resection, laparoscopic common bile duct exploration (LCBDE), or percutaneous transhepatic cholangioscopy. (2) For concomitant gallstones and common bile duct stones, the surgical approach can be selected as follows: laparoscopic cholecystectomy (LC) combined with endoscopic sphincterotomy (EST) or endoscopic papillary balloon dilatation, LC plus laparoscopic transcystic common bile duct exploration, LC plus LCBDE, and T-tube drainage or primary suture. (3) For concomitant intrahepatic and extrahepatic bile duct stones, laparoscopic liver resection, choledochoscopy through the hepatic duct orifice on the hepatectomy cross section, LCBDE, EST, and percutaneous transhepatic cholangioscopic lithotripsy could be used. According to the abovementioned principle, the minimally invasive treatment approach combined with the surgical technique and equipment condition will be significant in improving the therapeutic effect and avoiding the postoperative complications or hidden dangers of intrahepatic and extrahepatic bile duct stones. [ABSTRACT FROM AUTHOR]

Patients with atrial fibrillation (AF) are commonly managed with rhythm control strategy, but the natural history of this common arrhythmia leads itself to progression from paroxysmal to persistent or permanent AF, and recurrences are evident despite rhythm control treatments using cardioversion or catheter ablation. Numerous clinical factors have been associated with outcomes of rhythm control or arrhythmia progression in patients with AF. The more common factors have been used to formulate risk stratification scores, to help predict the outcomes of rhythm control treatments or AF progression. This review article provides an overview on the published clinical risk scores related to outcomes of rhythm control strategy or AF progression. [ABSTRACT FROM AUTHOR]

In previous work, we have developed a dual physically cross-linked hydrogel composed of poly (acrylamide-co-acrylic acid) (PAM-co-PAA) and polyvinyl alcohol (PVA), named as PVA/CP DN gel, by facile copolymerization and freezing/thawing. The PVA/CP DN gel is featuring both excellent mechanical properties and self-healing ability. Additionally, we have preliminarily found that the comonomer ratio for PVA/CP DN gel have great influence on the self-healing efficiency. In this research article, we will further discuss the mechanical and self-healing properties of the PVA/CP DN gel by varying the comonomer ratio of PAM-co-PAA. The results proved that the structure of DN will be loosen when the number of PAA segments exceed that of PAM. More PAA segments in copolymer make the PVA/CP DN gel have better elongation at break but weak in tensile strength and young's modulus because of less PVA crystalline domains formed in the gel. The energy dissipation value for the double-network hydrogel decrease with the addition of PAA segments, whereas self-healing efficiency of PVA/CP DN gel increased. Anyway, this work provides more information to further understand the effects of composition on the properties of dual physically cross-linked PVA/CP DN hydrogel. [ABSTRACT FROM AUTHOR]

Objective: To study the efficacy and safety of Shuanghuang Shengbai Granule (双黄升白颗粒, SSG), a traditional Chinese herbal medicine, on myelosuppression of cancer patients caused by chemotherapy. Methods: A total of 330 patients were randomly assigned to the treatment group (220 cases, analysed 209 cases) and the control group (110 cases, analysed 102 cases) with a 2:1 ratio by envelope method. The patients in the treatment group at the first day of chemotherapy started to take SSG for 14 days, while the patients in the control group took Leucogon Tablets. The changes of the blood routine, clinical symptoms and immune function in both groups were observed for safety and efficacy evaluation. Results: At the 7th day of chemotherapy, the white blood cells (WBCs) level in the treatment group was significantly higher than that in the control group ( P<0.05). After treatment, the WBCs rate in the normal range accounted for 50.2% in the treatment group, the myelosuppression of WBCs and neutrophil were mainly grade I, while 8.1% and 5.7% of patients emerged grade III and grade IV myelosuppression, respectively. The incidence of myelosuppression of the treatment group was significantly lower than that of the control group ( P<0.05). The total effective rate of Chinese medicine syndrome in the treatment group was significantly higher than that in the control group (84.2% vs. 72.5%, P<0.05). The immune cell levels in both groups were maintained in the normal range. Compared with that before treatment, the levels of CD3 and CD4 cells were significantly increased in the treatment group after treatment ( P<0.05). The discrepancy of CD3 and CD4 cell activity before and after treatment in both groups were significantly different ( P<0.05). No obvious adverse event occurred in both groups. Conclusion: SSG had a protection effect on bone marrow suppression, and alleviated the clinical symptoms together with clinical safety. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the effect of inhibition of calpain on retinal ganglion cell-5 (RGC-5) necroptosis following oxygen glucose deprivation (OGD). RGC-5 cells were cultured in Dulbecco's-modified essential medium and necroptosis was induced by 8-h OGD. PI staining and flow cytometry were performed to detect RGC-5 necrosis. The calpain expression was detected by Western blotting and immunofluorescence staining. The calpain activity was tested by activity detection kit. Flow cytometry was used to detect the effect of calpain on RGC-5 necroptosis following OGD with or without N-acetyl-leucyl-leucyl-norleucinal (ALLN) pre-treatment. Western blot was used to detect the protein level of truncated apoptosis inducing factor (tAIF) in RGC-5 cells following OGD. The results showed that there was an up-regulation of the calpain expression and activity following OGD. Upon adding ALLN, the calpain activity was inhibited and tAIF was reduced following OGD along with the decreased number of RGC-5 necroptosis. In conclusion, calpain was involved in OGD-induced RGC-5 necroptosis with the increased expression of its downstream molecule tAIF. [ABSTRACT FROM AUTHOR]

The nonparametric blur-kernel estimation, using either single image or multi-observation, has been intensively studied since Fergus et al.'s influential work (ACM Trans Graph 25:787-794, ). However, in the current literature there is always a gap between the two highly relevant problems; that is, single- and multi-shot blind deconvolutions are modeled and solved independently, lacking a unified optimization perspective. In this paper, we attempt to bridge the gap between the two problems and propose a rigorous and unified minimization function for single/multi-shot blur-kernel estimation by coupling the maximum-a-posteriori (MAP) and variational Bayesian (VB) principles. The new function is depicted using a directed graphical model, where the sharp image and the inverse noise variance associated with each shot are treated as random variables, while each blur-kernel, in difference from existing VB methods, is just modeled as a deterministic parameter. Utilizing a universal, three-level hierarchical prior on the latent sharp image and a Gamma hyper-prior on each inverse noise variance, single/multi-shot blur-kernel estimation is uniformly formulated as an $${\varvec{\fancyscript{l}}}_{{0.5}}$$ -norm-regularized negative log-marginal-likelihood minimization problem. By borrowing ideas of expectation-maximization, majorization-minimization, and mean field approximation, as well as iteratively reweighted least squares, all the unknowns of interest, including the sharp image, the blur-kernels, the inverse noise variances, as well as other relevant parameters are estimated automatically. Compared with most single/multi-shot blur-kernel estimation methods, the proposed approach is not only more flexible in processing multiple observations under distinct imaging scenarios due to its independence of the commutative property of convolution but also more adaptive in sparse image modeling while in the meanwhile with much less implementational heuristics. Finally, the proposed blur-kernel estimation method is naturally applied to two low-level vision problems, i.e., camera-shake deblurring and nonparametric blind super-resolution. Experiments on benchmark real-world motion blurred images, simulated multiple-blurred images, as well as both synthetic and realistic low-resolution blurred images are conducted, demonstrating the superiority of the proposed approach to state-of-the-art single/multi-shot camera-shake deblurring and nonparametric blind super-resolution methods. [ABSTRACT FROM AUTHOR]

Multiple sclerosis (MS) is the prototypical inflammatory demyelinating disease of the central nervous system (CNS), and MS results in physical and cognitive impairments, such as fatigue, pain, depression and bladder dysfunction. Though many therapies for MS have been developed, the safety profile and effectiveness of these therapies still need to be defined. Thus, new therapies for MS must be explored. Celastrol, a quinonemethide triterpene, is a pharmacologically active compound present in Thunder God Vine root extracts used to treat inflammatory and autoimmune diseases. Molecular studies have identified several molecular targets, which are mostly centered on the inhibition of IKK-NF-κB signaling. The animal model of experimental autoimmune encephalomyelitis (EAE) has been widely used in MS studies; thus, we tried to explore the role of celastrol in EAE development in this study. We demonstrated that the intraperitoneal injection of celastrol significantly attenuated EAE disease. Th17 cell responses in the peripheral lymph nodes in EAE mice were also inhibited by celastrol. We determined that celastroldownregulated cytokine production in bone-marrow derived dendritic cells (BMDCs). Accordingly, T cells that were co-cultured with either BMDCs pre-treated with celastrolor splenic DCs and then collected on day 7 after EAE immunizationshowed that Th17 cell polarization is suppressed in the above two situations. Moreover, celastrol was required for tissue-infiltrating DCs to sustain Th17 responses in the central nervous system (CNS). Taken together, the results of our study demonstrate that celastrol ameliorates EAE development by suppressing pathogenic Th17 responses; this finding offers a better understanding of the role of celastrol in EAE development as well as new proposals for clinical interventions. [ABSTRACT FROM AUTHOR]

The homeobox gene NKX6.1 was recently identified in cervical tumors. This study was designed to explore the clinical and prognostic significance of NKX6.1 further in patients with primary hepatocellular carcinoma (HCC). The expression levels of NKX6.1 were examined using real-time PCR, Western blotting, and immunohistochemistry in HCC cell lines and HCC tissues. The invasion capability of cell lines following silencing or overexpression of NKX6.1 was investigated by Transwell assay. Cells proliferation was tested by MTT assays. Epithelial-mesenchymal transition (EMT) marker expression levels were detected in relation to NKX6.1 expression. Correlation between NKX6.1 immunohistochemical staining, clinicopathologic parameters, and follow-up data of HCC patients was analyzed statistically. NKX6.1 expression was higher in HCC tissues compared to the adjacent noncancerous tissue. NKX6.1 overexpression was significantly correlated with tumor size, tumor differentiation, clinical stage, metastasis, and relapse. Kaplan-Meier analysis revealed that NKX6.1 overexpression was related to unfavorable 5-year disease-free survival and overall survival. Importantly, multivariate analysis indicated that NKX6.1 overexpression was an independent unfavorable marker for overall survival. Moreover, a significant relationship was observed between NKX6.1 and EMT marker expression levels, and NKX6.1 knockdown inhibited cell invasion, and overexpression of NKX6.1 promotes cell proliferation in vitro. NKX6.1 is upregulated in HCC and is a reliable prognostic marker for patients with HCC. [ABSTRACT FROM AUTHOR]

It is well-known that shaken cameras or mobile phones during exposure usually lead to motion blurry photographs. Therefore, camera shake deblurring or motion deblurring is required and requested in many practical scenarios. The contribution of this paper is the proposal of a simple yet effective approach for motion blur kernel estimation, i.e., blind motion deblurring. Though there have been proposed several methods for motion blur kernel estimation in the literature, we impose a type of non-stationary Gaussian prior on the gradient fields of sharp images, in order to automatically detect and purse the salient edges of images as the important clues to blur kernel estimation. On one hand, the prior is able to promote sparsity inherited in the non-stationarity of the precision parameters (inverse of variances). On the other hand, since the prior is in a Gaussian form, there exists a great possibility of deducing a conceptually simple and computationally tractable inference scheme. Specifically, the well-known expectation-maximization algorithm is used to alternatingly estimate the motion blur kernels, the salient edges of images as well as the precision parameters in the image prior. In difference from many existing methods, no hyperpriors are imposed on any parameters in this paper; there are not any pre-processing steps involved in the proposed method, either, such as explicit suppression of random noise or prediction of salient edge structures. With estimated motion blur kernels, the deblurred images are finally generated using an off-the-shelf non-blind deconvolution method proposed by Krishnan and Fergus (Adv Neural Inf Process Syst 22:1033-1041, ). The rationality and effectiveness of our proposed method have been well demonstrated by the experimental results on both synthetic and realistic motion blurry images, showing state-of-the-art blind motion deblurring performance of the proposed approach in the term of quantitative metric as well as visual perception. [ABSTRACT FROM AUTHOR]

Multi-frame image super-resolution (SR) has been intensively studied in recent years, aiming at reconstructing high-resolution images from several degraded ones (e.g., shift, blurred, aliased, and noisy). In the literature, one of the most popular SR frameworks is the maximum a posteriori model, where a spatially homogeneous image prior and manually adjusted regularization parameter are commonly used for the entire high-resolution image, thus ignoring local spatially adaptive properties of natural images. In this paper, a posterior mean approach is proposed for spatially adaptive multi-frame image super-resolution. First, a flexible Laplacian prior is proposed incorporating both the gradient and Hessian information of images, not only able to better preserve image structures, e.g., edge, texture, but also to suppress staircase effects in the flat regions. In the subsequent, a fully Bayesian SR framework is formulated, wherein the variational Bayesian method is utilized to simultaneously estimate the high-resolution image and unknown hyper-parameters for the image prior and noise. The final experimental results show that the proposed approach is highly competitive against existing algorithms, producing a super-resolved image with higher peak signal-to-noise ratio and better visual perception. [ABSTRACT FROM AUTHOR]

The reaction stability is a challenge in the 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-mediated oxidation of cellulose. Carbonate buffer solution (NaCO/NaHCO) was used to study pH effects on stability of the oxidation reaction in this work. The structure and morphology of cellulose fibers were characterized by XRD and SEM techniques, respectively. It was found that the carboxyl content of oxidized cellulose was changed with different composition ratio of buffer solutions. The highest carboxyl content was obtained at the molar ratio of 7:3. The NaClO addition, as well as reaction temperature, affected the process of the oxidation reaction. The carboxylate content of the oxidized cellulose was increased as the temperature and NaClO consumption increased. However, both temperature and NaClO consumption have negative effect on yield. SEM results showed that the morphology of oxidized cellulose fibers was significantly changed at high reaction temperature. XRD showed that the oxidized cellulose fibers maintained the crystal structure of cellulose I. However, the crystallinity was decreased from 56.4 to 40.8 % with increasing oxidation temperature from 25 to 40 °C. [ABSTRACT FROM AUTHOR]