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1.
New Phytol ; 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32040203

RESUMO

The fungus Verticillium dahliae causes vascular wilt disease on hundreds of plant species. Homologs of the bZIP transcription factor Atf1 are required for virulence in most pathogenic fungi, but the molecular basis for their involvement is largely unknown. We performed targeted gene deletion, expression analysis, biochemistry, and pathogenicity assays to demonstrate that VdAtf1 governs pathogenesis via the regulation of nitrosative resistance and nitrogen metabolism in V. dahliae. VdAtf1 controls pathogenesis via the regulation of nitric oxide (NO) resistance and inorganic nitrogen metabolism rather than oxidative resistance and is important for penetration peg formation in V. dahliae. VdAtf1 affects ammonium and nitrate assimilation in response to various nitrogen sources. VdAtf1 can be involved in regulating the expression of VdNut1. VdAtf1 responds to NO stress by strengthening the fungal cell wall, and by causing over-accumulation of methylglyoxal and glycerol, which in turn impacts NO detoxification. We also verified that the VdAtf1 ortholog in Fusarium graminearum mediates nitrogen metabolism, suggesting conservation of this function in related plant pathogenic fungi. Our findings revealed new functions of VdAtf1 in pathogenesis, response to nitrosative stress, and nitrogen metabolism in V. dahliae. The results provide novel insights into the regulatory mechanisms of the transcription factor VdAtf1 in virulence.

2.
Theor Appl Genet ; 133(3): 951-966, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31893289

RESUMO

KEY MESSAGE: Twelve potato accessions were selected to represent two principal views on potato taxonomy. The genomes were sequenced and analyzed for structural variation (copy number variation) against three published potato genomes. The common potato (Solanum tuberosum L.) is an important staple crop with a highly heterozygous and complex tetraploid genome. The other taxa of cultivated potato contain varying ploidy levels (2X-5X), and structural variations are common in the genomes of these species, likely contributing to the diversification or agronomic traits during domestication. Increased understanding of the genomes and genomic variation will aid in the exploration of novel agronomic traits. Thus, sequencing data from twelve potato landraces, representing the four ploidy levels, were used to identify structural genomic variation compared to the two currently available reference genomes, a double monoploid potato genome and a diploid inbred clone of S. chacoense. The results of a copy number variation analysis showed that in the majority of the genomes, while the number of deletions is greater than the number of duplications, the number of duplicated genes is greater than the number of deleted ones. Specific regions in the twelve potato genomes have a high density of CNV events. Further, the auxin-induced SAUR genes (involved in abiotic stress), disease resistance genes and the 2-oxoglutarate/Fe(II)-dependent oxygenase superfamily proteins, among others, had increased copy numbers in these sequenced genomes relative to the references.

3.
Appl Opt ; 58(36): 9861-9869, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31873631

RESUMO

It is important to enhance the contrast and remove the speckle noise for optical coherence tomography (OCT) images. In this paper, we propose a selective retinex enhancement method based on the fuzzy c-means (FCM) clustering algorithm to enhance only the structure part in OCT images and combines with the block-matching 3D (BM3D) algorithm for filtering. In the proposed selective retinex enhancement method, we first calculate the feature image of the original image, which includes the mean value and standard deviation of each pixel in the original image and its correlation image. Second, by applying the FCM clustering algorithm to the feature image, a mask is generated that can distinguish the structure part from the background part in the OCT image. Then, the mask is applied to the multi-scale retinex algorithm, and only the structure part in the OCT image is enhanced. Moreover, the BM3D method is applied to filter the enhanced image. Experimental results demonstrate that the proposed method performs impressively in improving the contrast and removing the speckle noise of OCT images, and it provides better quantitative performance in terms of signal-to-noise ratio, contrast-to-noise ratio, equivalent number of looks, and the edge preservation parameter $ \beta $ß.

4.
Gerontologist ; 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31773140

RESUMO

BACKGROUND AND OBJECTIVES: Decisions about long-term care and financing can be difficult to comprehend, consider, and communicate. In a previous needs assessment, families in rural areas requested a patient-facing website; however, questions arose about the acceptability of an online tool for older adults. This study engaged older adults and family caregivers in (a) designing and refining an interactive, tailored decision aid website, and (b) field testing its utility, feasibility, and acceptability. RESEARCH DESIGN AND METHODS: Based on formative work, the research team engaged families in designing and iteratively revising paper drafts, then programmed a tailored website. The field test used the ThinkAloud approach and pre-/postquestionnaires to assess participants' knowledge, decisional conflict, usage, and acceptability ratings. RESULTS: Forty-five older adults, family members, and stakeholders codesigned and tested the decision aid, yielding four decision-making steps: Get the Facts, What Matters Most, Consider Your Resources, and Make an Action Plan. User-based design and iterative storyboarding enhanced the content, personal decision-making activities, and user-generated resources. Field-testing participants scored 83.3% correct on knowledge items and reported moderate/low decisional conflict. All (100%) were able to use the website, spent an average of 26.3 min, and provided an average 87.5% acceptability rating. DISCUSSION AND IMPLICATIONS: A decision aid website can educate and support older adults and their family members in beginning a long-term care plan. Codesign and in-depth interviews improved usability, and lessons learned may guide the development of other aging decision aid websites.

5.
Opt Express ; 27(22): 32378-32391, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31684452

RESUMO

The fringe skeleton method is the most straightforward analysis method for phase extraction and widely used in dynamic measurement. Binarization is often required in this method. In the traditional binarization methods, filtering is often a necessary step prior to binarization due to the influence of intrinsic speckle noises in ESPI fringe patterns. In this paper, we propose a binarization method based on local entropy and fuzzy c-means (FCM) clustering algorithm. In this method, the pixels in the given ESPI fringe pattern are clustered into white fringes and black fringes according to their local entropy instead of the original intensity information. There is no need to perform the filtering preprocessing, because the intrinsic speckle noises are utilized as essentials. We evaluate the performance of our method by applying it to the computer-simulated and real fringe patterns. Experimental results demonstrate that the proposed method can achieve the desired binarization results, and the binarization results can give desired skeleton results.

6.
Appl Opt ; 58(27): 7523-7530, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31674404

RESUMO

The fringe orientation is an important feature of the electronic speckle interferometry (ESPI) fringe pattern. Accurate and efficient calculation of the fringe orientation is very important for subsequent electronic speckle processing such as skeleton extraction and image filtering. To accurately and efficiently estimate fringe orientation, we propose an effective method based on a convolutional neural network. In the proposed method, the network needs clean-noisy image pairs to train and noisy images with theoretical value to test. The aligned noise-free ESPI fringe pattern orientation fields are fairly good estimations for the corresponding noise ones. After the model training is done, the other multiple ESPI fringe patterns are fed to the trained network simultaneously; the corresponding orientation results can be obtained accurately and efficiently. The advantage of using this method to extract the orientation is that the fringe orientation information can be extracted accurately and efficiently without complicated parameter adjustment. We evaluate the performance of our method via applying our method to the computer-simulated and experimentally acquired ESPI fringe patterns and comparing the results with those of three extensively used methods.

7.
Nanomaterials (Basel) ; 9(10)2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31658659

RESUMO

A flexible filter paper based composite electrode was prepared via the convenient one-step synthesis of silver doped graphene for the first time, followed by in-situ polymerization of aniline monomers. Using L-ascorbic acid for simultaneous reduction of grapheme oxide and silver nitrate, we provided a new and green method to prepare graphene hybrid sheets without toxicity. It was found that the as-fabricated hybrid electrode formed a three-dimensional porous architecture, which not only increased the specific surface area of composite, but also facilitated the ion diffusion of the electrolyte. In addition, according to the tests of electrochemical performances, the flexible hybrid electrode subsequently exhibited exceptional specific capacitance of 437.3 F/g, energy density of 1133.5 W·h/kg and power density of 88.8 kW/kg, respectively. Meanwhile, the as-prepared hybrid demonstrated a good cycling stability with only 10.99% specific capacitance deterioration after 5000 times of cycling. This preparation technology presented here shows great potential for the development and application of wearable and portable energy storage devices, particularly for flexible supercapacitors. Moreover, this study puts forward a general, simple and low-cost route of fabricating a novel flexible electrode on a large scale, eventually for environmental protection.

8.
Nanomaterials (Basel) ; 9(9)2019 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-31546805

RESUMO

An asymmetric supercapacitor was prepared on a sheet of filter paper with two modified surfaces acting as electrodes in 1 M potassium hydroxide aqueous solution. By choosing carbon nanotubes and two different kinds of metal oxides (zinc oxide and ferro ferric oxide) as electrode materials, the asymmetric supercapacitor was successfully fabricated. The results showed that this device exhibited a wide potential window of 1.8 V and significantly improved electrochemical performances of its counterparts. Particularly, the one-sheet asymmetric supercapacitor demonstrated high energy density of 116.11 W h/kg and power density 27.48 kW/kg, which was attributed to the combined action and shortened distance between the two electrodes, respectively. Besides, it showed superior electrochemical cycling stability with 87.1% capacitance retention under room temperature. These outstanding results can not only give researchers new insights into compact energy storage systems, but they also provide a good prospect for flexible asymmetric supercapacitors.

9.
Appl Opt ; 58(23): 6233-6243, 2019 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-31503765

RESUMO

In this paper, we propose a total variation based on block matching 3D (BM3D-TV method), which includes the total variation regular term, the data fidelity term, and the block matching term. In addition, we also propose a fast numerical algorithm based on the split Bregman iteration for the proposed method. By assigning suitable weights to the data fidelity term and block matching term, the image noise reduction and the image structural characteristics can be matched optimally. We test the proposed method on six human retinal and one mouse skin optical coherence tomography (OCT) images respectively, and also compare it with total variation (TV) and BM3D, which were proved to be effective in denoising. The performances of these methods are quantitatively evaluated in terms of the signal-to-noise ratio, the contrast-to-noise ratio, and the averaged equivalent number of homogeneous areas at the aspects of speckle reduction and structure protection. Vast experiments show that the BM3D-TV method can effectively reduce speckle noise in OCT images, protect important structural information and improve image quality, compared with the BM3D and TV methods.

10.
mSphere ; 4(4)2019 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-31292234

RESUMO

Verticillium dahliae causes destructive vascular wilt diseases on more than 200 plant species, including economically important crops and ornamental trees worldwide. The melanized microsclerotia enable the fungus to survive for years in soil and are crucial for its disease cycle. Previously, we found that the VdPbs2-VdHog1 (V. dahliae Pbs2-V. dahliae Hog1) module plays key roles in microsclerotial formation, stress responses, and virulence in V. dahliae In this study, two mitogen-activated protein kinase kinase kinases (MAPKKKs) homologous to Ssk2p and Ste11p, which activate the Pbs2p-Hog1p module by phosphorylation in budding yeast, were identified in the genome of V. dahliae Both ΔVdSsk2 (V. dahliae Ssk2) and ΔVdSte11 strains showed severe defects in microsclerotial formation and melanin biosynthesis, but the relative importance of these two genes in microsclerotial development was different. Deletion of VdSsk2, but not VdSte11, affected responses to osmotic stress, fungicidal response, and cell wall stressors. The ΔVdSsk2 strain exhibited a significant reduction in virulence, while the ΔVdSte11 strain was nonpathogenic due to failure to penetrate and form hyphopodia. Phosphorylation assays demonstrated that VdSsk2, but not VdSte11, can phosphorylate VdHog1 in V. dahliae Moreover, VdCrz1, encoding a calcineurin-responsive zinc finger transcription factor and a key regulator of calcium signaling in fungi, was misregulated in the ΔVdSsk2, ΔVdPbs2, and ΔVdHog1 mutants.IMPORTANCE These data provide insights into the distinctive functions of VdSsk2 and VdSte11 in pathogenicity, stress adaptation, and microsclerotial formation in V. dahliae.

11.
Ren Fail ; 41(1): 636-643, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31269846

RESUMO

Background: Mineral and bone disorder (MBD) in hemodialysis patients is associated with increased morbidity and mortality. Studies on the MBD status of hemodialysis patients at high altitudes are extremely limited. Methods: A total of 146 hemodialysis patients from 5 local hospitals across all districts with hemodialysis centers in the Tibetan Plateau were enrolled in this cross-sectional study. Parameters related to MBD, including serum phosphorus (P), calcium (Ca), and intact parathyroid hormone (iPTH) levels, were measured. The achievement of MBD goals was compared with the achievement in the Dialysis Outcomes and Practice Study (DOPPS) 3, DOPPS 4 and a multicenter study of MBD in China. Factors associated with hyperphosphatemia were examined. Results: Altogether, 146 hemodialysis patients were recruited from the Tibetan Plateau. According to the K/DIGO guidelines, there were low achievement rates for serum Ca (40.4%), P (29.7%), and iPTH (47.1%). As for the (KDOQI) guidelines, the rates of achievement of defined targets were 38.4%, 33.7% and 16.4% for serum Ca, P and iPTH, respectively. The percentages of patients reaching the KDOQI targets for corrected Ca, P, and iPTH were significantly lower for Tibetan patients than the percentages found in DOPPS 3 (38.4% vs. 50.4%, 33.7% vs. 49.8%, and 16.4% vs. 31.4%, respectively, all p < .001) and DOPPS 4 (38.4% vs. 56.0%, 33.7% vs. 54.5%, and 16.4% vs. 35.3%, respectively, all p < .001). The percentage of patients reaching the KDOQI targets for iPTH was significantly lower in Tibet than in the plain areas of China (16.4% vs. 26.5%, p < .001). The proportion of patients with hypocalcemia was higher in Tibet than in the plain areas (44.5% vs. 19.4%, p < .001). The percentage of local patients with optimal P was significantly higher for patients with an activated vitamin D prescription than for patients without an activated vitamin D prescription (45.3% vs. 19.3%, p < .001). Age and the activated vitamin D prescription were independently associated with hyperphosphatemia. Conclusion: The MBD status of hemodialysis patients in Tibet is far from the ideal level. High altitude is one of the possible causes of the differences found, but not the principal one. It is necessary for medical staff in Tibet to improve the detection and treatment of MBD.


Assuntos
Distúrbio Mineral e Ósseo na Doença Renal Crônica/diagnóstico , Hiperfosfatemia/diagnóstico , Diálise Renal/efeitos adversos , Insuficiência Renal Crônica/terapia , Adulto , Cálcio/sangue , Distúrbio Mineral e Ósseo na Doença Renal Crônica/sangue , Estudos Transversais , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Hormônio Paratireóideo/sangue , Fósforo/sangue , Tibet , Vitamina D/administração & dosagem
12.
Sensors (Basel) ; 19(13)2019 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-31284562

RESUMO

This work presents a novel remote control solution for an Autonomous Vehicle (AV), where the system structure is split into two sides. Both sides are assumed to be synchronized and linked through a communication network, which introduces time-varying delays and packet disorder. An Extended Kalman Filter (EKF) is used to cope with the non-linearities that appear in the global model of the AV. The EKF fuses the data provided by the sensing devices of the AV in order to estimate the AV state, reducing the noise effect. Additionally, the EKF includes an h-step-ahead state prediction stage, which, together with the consideration of a packet-based control strategy, enables facing the network-induced delays. Since the AV position is provided by a camera, which is a slow sensing device, a dual-rate controller is required to achieve certain desired (nominal) dynamic control performance. The use of a dual-rate control framework additionally enables saving network bandwidth and deals with packet disorder. As the path-tracking control algorithm, pure pursuit is used. Application results show that, despite existing communication problems and slow-rate measurements, the AV is able to track the desired path, keeping the nominal control performance.

13.
Bioresour Technol ; 291: 121862, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31357047

RESUMO

This study evaluated the feasibility of microbial fuel cells (MFCs) for simultaneous electricity generation and degradation of phenolic compounds. The voltage generation was inhibited by 36.18-63.90%, but the degradation rate increased by 146.15-392.31% when the initial concentration of syringic acid (SA), vanillic acid (VA), and 4-hydroxybenzoic acid (HBA) increased from 0.3 to 3.0 g/L. The collaboration among the functional microbes significantly enhanced the degradation rate of parent compounds and their intermediates in MFCs systems, while the accumulated intermediates severely inhibited their complete mineralization in fermentative systems. High-throughput sequencing showed that the growth of fermentative bacteria prevailed, but electrogenic bacteria were inhibited in the anode microbial community (AMC) under high concentrations of phenolic compounds (3.0 g/L). These findings provide a better understanding of the dynamic shift and synergy effects of the AMC to evaluate its potential for the treatment of phenolic-containing wastewater.


Assuntos
Fontes de Energia Bioelétrica/microbiologia , Microbiota , Fenóis/metabolismo , Eletricidade , Eletrodos , Fermentação
14.
Nanoscale ; 11(24): 11696-11708, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31179463

RESUMO

Peptide-based biomaterials are a promising class of antimicrobial agents that work by physically damaging bacterial cell membranes rather than targeting intracellular factors, resulting in less susceptibility to drug resistance. Herein we report the synthesis of cationic, star-shaped polypeptides with 3 to 8 arms and their evaluation as antimicrobial agents against different types of bacteria. The effects of the arm number and side chain group on their antimicrobial activities were systematically investigated. Compared to their linear counterparts, these star-shaped polypeptides exhibited potent antibacterial activity (which may involve adhesion and disruption processes). The increase of the arm number can efficiently increase the antibacterial activities up until 8 arms, which did not exhibit further improvement of antibacterial activities. Poly(l-lysine) (PLL) modified with an indole group (PLL-g-indo) exhibited the best antibacterial activity among all grafted copolypeptides and improved cytotoxic selectivity towards pathogens over mammalian cells without compromising their hemolytic activities. In vivo studies showed that the star-shaped PLL-g-indo can effectively suppress Enterohaemorrhagic E. coli (EHEC) infection and attenuate the clinical symptoms in mice, suggesting that they are promising antimicrobial agents.


Assuntos
Antibacterianos , Escherichia coli Êntero-Hemorrágica/metabolismo , Síndrome Hemolítico-Urêmica/tratamento farmacológico , Polilisina , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Síndrome Hemolítico-Urêmica/metabolismo , Síndrome Hemolítico-Urêmica/patologia , Camundongos , Polilisina/química , Polilisina/farmacologia
15.
Chemosphere ; 234: 260-268, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31220659

RESUMO

Phenolic compounds are problematic byproducts generated from lignocellulose pretreatment. In this study, the feasibility degradation of syringic acid (SA), vanillic acid (VA), and 4-hydroxybenzoic acid (HBA) by Bio-Electro-Fenton (BEF) system with a novel Fe-Mn/graphite felt (Fe-Mn/GF) composite cathode were investigated. The nano-scale Fe-Mn multivalent composite catalyst with core shell structure distributed more evenly on GF surface to form a catalyst layer with higher oxygen reduction reaction performance. Accordingly, the maximum power density generated with Fe-Mn/GF cathode was 48.1% and 238.9% higher than Fe/GF and GF respectively, which further enhanced the in situ generation of H2O2 due to the superiority of nano-scale core shell structure and synergistic effect of Fe and Mn species. The degradation efficiency of the three phenolic compounds in the BEF system could reached 100% after optimization of influencing parameters. Furthermore, a possible SA degradation pathway by BEF process in the present system was proposed based on the detected intermediates. These results demonstrated an efficient approach for the degradation of phenolic compounds derived from lignocellulose hydrolysates.


Assuntos
Eletroquímica , Eletrodos , Grafite/química , Peróxido de Hidrogênio , Ferro/química , Manganês/química , Fenóis/química , Catálise
16.
Appl Opt ; 58(13): 3338-3346, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31044829

RESUMO

The denoising of electronic speckle pattern interferometry (ESPI) fringe patterns is a key step in the application of ESPI. In this paper, we propose a method for batch denoising of ESPI fringe patterns based on a convolution neural network (CNN). In the proposed method, the network is first trained by our training dataset, which consists of the noisy ESPI fringe patterns and the corresponding noise-free images. We propose a new computer-simulated method of ESPI fringe patterns to create our training dataset. After training, the other multi-frame ESPI fringe patterns to be processed are fed to the trained network simultaneously, and the corresponding denoising images can be obtained in batches. We demonstrate the performance of the proposed method via application to 50 computer-simulated ESPI fringe patterns and three groups of experimentally obtained ESPI fringe patterns. The experimental results show that our method can obtain desired results even when the quality of ESPI fringe images is considerably low because of variable density, high noise, and low contrast, and our method can denoise multi-frame fringe patterns simultaneously. Moreover, we use the computer-simulated ESPI fringe patterns to train the network; after training, the trained network can be used to denoise either computer-simulated ESPI fringe patterns or the experimentally obtained ESPI fringe patterns. The proposed method is especially suitable for processing a large number of ESPI fringe patterns.

17.
Materials (Basel) ; 12(8)2019 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-31013898

RESUMO

A novel high-performance carbon foam (CF) was fabricated through the addition of phenolic resin (PR) into a coal tar pitch (CTP) based precursor. The effects of mass fraction of a PR additive on the crystalline structures, morphologies, compressive strength (σ) and thermal conductivity (λ) of resultant CF material were investigated systematically. Characterization showed a strong dependence of CF's performance from the composition and optical texture of the precursor, which were mainly depending on the polycondensation and polymerization reactions between PR and raw CTP. Comparing with the strength of pristine CF at 6.5 MPa, the σ of mCF-9 (13.1 MPa) was remarkably enhanced by 100.1%. However, the λ of mCF-9 substantially reduced to 0.9 m-1K-1 compared with 18.2 W m-1K-1 of pristine CF. Thus, this modification strategy to produce microporous CF materials from raw CTP provides a new protocol for the fabrication of high-performance carbon based materials.

18.
Front Microbiol ; 10: 606, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30967857

RESUMO

Verticillium dahliae causes vascular wilt disease on over 200 plant species worldwide. This fungus forms melanized microsclerotia which help it to survive under adverse conditions and these structures are vital to the disease spread. Here, we identified and characterized a V. dahliae homolog to of the Saccharomyces cerevisiae Ssk1, a response regulator of the two-component system. Herein, we demonstrated that the VdSsk1 deletion strains were more sensitive to various stresses, including oxidative stress conferred by H2O2 and sodium nitroprusside dihydrate, while the mutants confered higher resistance to fungicides such as fludioxonil and iprodione. Furthermore, disruption of VdSsk1 resulted in significant downregulation of melanin biosynthesis-related genes but did not affect microsclerotial development. Phosphorylation of VdHog1 was not detected in the VdSsk1 deletion strains under the treatment of sorbitol, indicating that phosphorylation of VdHog1 is dependent on VdSsk1. Finally, we demonstrated that VdSsk1 is required for full virulence. Taken together, this study suggests that VdSsk1 modulates stress response, melanin biosynthesis and virulence of V. dahliae.

19.
J Rheumatol ; 46(12): 1582-1588, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30936280

RESUMO

OBJECTIVE: Cauda equina syndrome (CES) is a rare neurologic complication of longstanding ankylosing spondylitis (AS). It is unclear what causes CES, and no proven or effective therapy has been reported to date. We have encountered 6 patients with longstanding AS diagnosed with CES. We set about to study their features, review the literature, and generate hypotheses regarding pathophysiology, as well as to speculate on the possibilities of early recognition and prevention. METHODS: We obtained permission from 6 patients with longstanding AS and CES to access their medical records and imaging studies for research purposes related to this paper. We collected and reviewed each patient's medical history, imaging studies, disease duration, past therapies especially those that relate to AS, laboratory data, as well as any treatment they received for CES and followup results of each case to the present time. RESULTS: The 6 cases of CES with AS have remarkable similarity to each other in that several decades of the disease had passed before neurologic symptoms and later signs appeared. All cases have fused spines and facet joints without spinal fractures, spinal stenosis, or disc herniation. CONCLUSION: CES is a rare yet debilitating neurologic complication of longstanding AS. The pathophysiology and treatments are far from clear. We postulate that chronic enthesitis of the vertebral column initiates the process that results in dural stiffening and formation of ectasias, causing downstream nerve root damage.

20.
ACS Appl Mater Interfaces ; 11(15): 14120-14125, 2019 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-30908002

RESUMO

Mn3O4 is a potential anode for alkali-metal (Li/Na/K)-ion batteries because of the high capacity, abundant resources, and eco-friendliness. However, its ion storage performance is limited by poor electronic conductivity and large volume expansion during the charging/discharging process. In this study, we presented a facile dissolution strategy to fabricate ultrathin nanosheet-assembled hierarchical Mn3O4/graphene microflowers, realizing enhanced alkali-metal-ion storage performance. The synthetic mechanism was proven as the selective dissolution of vanadium via controlled experiments with different reaction times. The as-synthesized composites showed high lithium storage capacity (about 900 mA h g-1) and superior cyclability (∼400 mA h g-1 after 500 cycles). In addition, when evaluated as a Na-ion battery anode, the reversible capacity of about 200 mA h g-1 was attained, which remained at 167 mA h g-1 after 200 cycles. Moreover, to the best of our knowledge, the potassium storage properties of Mn3O4 were evaluated for the first time and a reversible capacity of about 230 mA h g-1 was achieved. We believe that our findings will be instructive for future investigations of high-capacity anode materials for alkali-metal-ion batteries.

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