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1.
Microsurgery ; 41(2): 133-139, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33165984

RESUMO

BACKGROUND: The posterior tibial artery perforator (PTAP) flap is a useful tool for reconstruction of soft tissue defects in the leg. However, the size and reliability of the flap largely depends on the quality of the perforator by which the flap is supplied, and the sensory recovery of the flap is limited. In this study, the anatomy of the saphenous nerve branches and their accompanying vessels was investigated, and a free extended PTAP flap with the neurovascular plexus of a saphenous nerve branch was designed for large soft tissue and sensory reconstruction in a series of clinical cases. METHODS: Sixteen adult cadaveric legs perfused with red latex in the femoral artery were dissected. The number and location of the saphenous nerve branches and the features of their accompanying vessels were dissected and studied. From January 2016 to December 2017, six patients with soft tissue defects ranged from 8 × 2.5 cm to 21 × 4 cm were repaired by the free extended PTAP flap. The patients' average age was 48 years. The causes of the defects included machine injuries in three patients and traffic injuries in the other three. The defects located at the hand in three cases, foot in two cases, and ankle in one case. The flap was designed based on the perforators of the posterior tibial artery and included a branch of saphenous nerve. The perforator pedicle and the nerve branch were connected to the vessels and nerve in the recipient site, respectively. RESULTS: The saphenous nerve gave off 5.8 ± 1.1 branches, with a relatively constant one issuing 8.1 ± 0.7 cm distal to the medial femoral condyle. Every nerve branch had an accompanying vessel, which connected with the PTAPs and supplied the skin. The size of the flap ranged from 10 × 3.5 cm to 23 × 5 cm. All of the flaps survived completely without complications. Follow-up varied from 6 to 12 months. All the patients obtained cold/hot sensation and pain sensation. The results of Semmes-Weinstein monofilament test ranged from 4.31(2 g) to 5.46 (26 g), and the 2-point discrimination test varied from 20 to 35 mm. CONCLUSION: The free extended PTAP flap, containing the saphenous nerve branch and its accompanying vessels, may be an alternative for large soft tissue reconstruction with improved sensation recovery.


Assuntos
Retalho Perfurante , Procedimentos de Cirurgia Plástica , Lesões dos Tecidos Moles , Adulto , Humanos , Reprodutibilidade dos Testes , Transplante de Pele , Lesões dos Tecidos Moles/cirurgia , Artérias da Tíbia/cirurgia , Resultado do Tratamento
2.
Sensors (Basel) ; 21(6)2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33799769

RESUMO

A novel capacitive humidity sensor based on carbon black/polyimide composites is presented in this paper. The details of the fabrication, sensor characteristics, and effect of the carbon black additive are described. It was confirmed that the polyimide composite filled with a tiny amount of carbon black was suitable for a humidity sensing dielectric. The humidity sensors with three different dielectrics, which were pure polyimide, 0.01 wt% carbon black/polyimide, and 0.05 wt% carbon black/polyimide, were fabricated by a micro-electro-mechanical-system (MEMS) process. As the amount of the carbon black additive increased, the sensitivity of the humidity sensor increased. The humidity sensor with 0.05 wt% of carbon black had a much higher sensitivity of 15.21% (20-80% RH, 0.2535%/% RH) than that of the sensor with pure polyimide, which was 9.73% (0.1622%/% RH). The addition of carbon black also led to an enhancement in the hysteresis and response speed. The hysteresis of the humidity sensor decreased from 2.17 to 1.80% when increasing the amount of the carbon black additive. The response speed of the humidity sensor with 0.05 wt% of carbon black was measured to be ~10% faster than that of the sensor with pure polyimide. The long-term stability of the humidity sensors was demonstrated as well.

3.
Appl Microbiol Biotechnol ; 102(19): 8511-8524, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30088019

RESUMO

Persisters represent a small bacterial population that is dormant and that survives under antibiotic treatment without experiencing genetic adaptation. Persisters are also considered one of the major reasons for recalcitrant chronic bacterial infections. Although several mechanisms of persister formation have been proposed, it is not clear how cells enter the dormant state in the presence of antibiotics or how persister cell formation can be effectively controlled. A fatty acid compound, cis-2-decenoic acid, was reported to decrease persister formation as well as revert the dormant cells to a metabolically active state. We reasoned that some fatty acid compounds may be effective in controlling bacterial persistence because they are known to benefit host immune systems. This study investigated persister cell formation by pathogens that were exposed to nine fatty acid compounds during antibiotic treatment. We found that three medium chain unsaturated fatty acid ethyl esters (ethyl trans-2-decenoate, ethyl trans-2-octenoate, and ethyl cis-4-decenoate) decreased the level of Escherichia coli persister formation up to 110-fold when cells were exposed to ciprofloxacin or ampicillin antibiotics. RNA sequencing analysis and gene deletion persister studies elucidated that these fatty acids inhibit bacterial persistence by regulating antitoxin HipB. A similar persister cell reduction was observed for pathogenic E. coli EDL933, Pseudomonas aeruginosa PAO1, and Serratia marcescens ICU2-4 strains. This study demonstrates that fatty acid ethyl esters can be used to disrupt bacterial dormancy to combat persistent infectious diseases.


Assuntos
Antitoxinas/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas de Escherichia coli/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Ésteres/farmacologia , Ácidos Graxos/farmacologia , Antibacterianos/farmacologia , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/metabolismo , Ciprofloxacina/farmacologia , Proteínas de Escherichia coli/metabolismo , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/metabolismo , Serratia marcescens/efeitos dos fármacos , Serratia marcescens/metabolismo
4.
Korean J Parasitol ; 52(1): 69-73, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24623885

RESUMO

Sparganosis is a parasitic infection caused by the plerocercoid tapeworm larva of the genus Spirometra. Although the destination of the larva is often a tissue or muscle in the chest, abdominal wall, extremities, eyes, brain, urinary tract, spinal canal, and scrotum, intramuscular sparganosis is uncommon and therefore is difficult to distinguish from a soft tissue tumor. We report a case of intramuscular sparganosis involving the gastrocnemius muscle in an elderly patient who was diagnosed using ultrasonography and MRI and treated by surgical excision. At approximately 1 cm near the schwannoma at the right distal sciatic nerve, several spargana worms were detected and removed.


Assuntos
Músculo Esquelético/patologia , Músculo Esquelético/parasitologia , Esparganose/diagnóstico , Esparganose/patologia , Spirometra/isolamento & purificação , Idoso , Animais , Histocitoquímica , Humanos , Imageamento por Ressonância Magnética , Masculino , Microscopia , Músculo Esquelético/cirurgia , Esparganose/parasitologia , Esparganose/cirurgia , Ultrassonografia
5.
Micromachines (Basel) ; 14(5)2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37241589

RESUMO

Aluminum nitride (AlN) thin film/molybdenum (Mo) electrode structures are typically required in microelectromechanical system applications. However, the growth of highly crystalline and c-axis-oriented AlN thin films on Mo electrodes remains challenging. In this study, we demonstrate the epitaxial growth of AlN thin films on Mo electrode/sapphire (0001) substrates and examine the structural characteristics of Mo thin films to determine the reason contributing to the epitaxial growth of AlN thin films on Mo thin films formed on sapphire. Two differently oriented crystals are obtained from Mo thin films grown on sapphire substrates: (110)- and (111)-oriented crystals. The dominant (111)-oriented crystals are single-domain, and the recessive (110)-oriented crystals comprise three in-plane domains rotated by 120° with respect to each other. The highly ordered Mo thin films formed on sapphire substrates serve as templates for the epitaxial growth by transferring the crystallographic information of the sapphire substrates to the AlN thin films. Consequently, the out-of-plane and in-plane orientation relationships among the AlN thin films, Mo thin films, and sapphire substrates are successfully defined.

6.
Nanomaterials (Basel) ; 13(6)2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36986021

RESUMO

The effects of electrode materials (top and bottom) and the operating ambiances (open-air and vacuum) on the MgFx-based resistive random-access memory (RRAM) devices are studied. Experiment results show that the device's performance and stability depend on the difference between the top and bottom electrodes' work functions. Devices are robust in both environments if the work function difference between the bottom and top electrodes is greater than or equal to 0.70 eV. The operating environment-independent device performance depends on the surface roughness of the bottom electrode materials. Reducing the bottom electrodes' surface roughness will reduce moisture absorption, minimizing the impact of the operating environment. Ti/MgFx/p+-Si memory devices with the minimum surface roughness of the p+-Si bottom electrode show operating environment-independent electroforming-free stable resistive switching properties. The stable memory devices show promising data retentions of >104 s in both environments with DC endurance properties of more than 100 cycles.

7.
Nat Biomed Eng ; 7(1): 38-55, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36550307

RESUMO

The microbiome modulates host immunity and aids the maintenance of tolerance in the gut, where microbial and food-derived antigens are abundant. Yet modern dietary factors and the excessive use of antibiotics have contributed to the rising incidence of food allergies, inflammatory bowel disease and other non-communicable chronic diseases associated with the depletion of beneficial taxa, including butyrate-producing Clostridia. Here we show that intragastrically delivered neutral and negatively charged polymeric micelles releasing butyrate in different regions of the intestinal tract restore barrier-protective responses in mouse models of colitis and of peanut allergy. Treatment with the butyrate-releasing micelles increased the abundance of butyrate-producing taxa in Clostridium cluster XIVa, protected mice from an anaphylactic reaction to a peanut challenge and reduced disease severity in a T-cell-transfer model of colitis. By restoring microbial and mucosal homoeostasis, butyrate-releasing micelles may function as an antigen-agnostic approach for the treatment of allergic and inflammatory diseases.


Assuntos
Colite , Doenças Inflamatórias Intestinais , Hipersensibilidade a Amendoim , Camundongos , Animais , Micelas , Butiratos
8.
Micromachines (Basel) ; 13(4)2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35457909

RESUMO

This study investigates the switching characteristics of the silicon oxynitride (SiOxNy)-based bipolar resistive random-access memory (RRAM) devices at different operating ambiances at temperatures ranging from 300 K to 77 K. The operating ambiances (open air or vacuum) and temperature affect the device's performance. The electroforming-free multilevel bipolar Au/Ni/SiOxNy/p+-Si RRAM device (in open-air) becomes bilevel in a vacuum with an on/off ratio >104 and promising data retention properties. The device becomes more resistive with cryogenic temperatures. The experimental results indicate that the presence and absence of moisture (hydrogen and hydroxyl groups) in open air and vacuum, respectively, alter the elemental composition of the amorphous SiOxNy active layer and Ni/SiOxNy interface region. Consequently, this affects the overall device performance. Filament-type resistive switching and trap-controlled space charge limited conduction (SCLC) mechanisms in the bulk SiOxNy layer are confirmed.

9.
Nanoscale ; 14(10): 3738-3747, 2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35187553

RESUMO

This study investigates the temperature-independent switching characteristics of magnesium fluoride (MgFx) based bipolar resistive memory devices at temperatures ranging from 300 K down to 77 K. Filament type resistive switching at the interface of Ti/MgFx and the trap-controlled space charge limited conduction (SCLC) mechanism in the bulk MgFx layer are confirmed. The experimental results indicate that the operating environment and temperature critically control the resistive switching performance by varying the non-stoichiometry of the amorphous MgFx active layer and Ti/MgFx interface region. The gaseous atmosphere (open air or vacuum) affects device performances such as the electroforming process, on-state current, off-state current, on/off ratio, SET/RESET voltage and endurance of resistive-switching memory devices. After electroforming, the device performance is independent of temperature variation. The Ti/MgFx/Pt memory devices show promising data retention for >104 s in a vacuum at room temperature and 77 K with the DC endurance property for more than 150 cycles at 77 K. The devices have great potential for future temperature-independent electronic applications.

10.
Nanomaterials (Basel) ; 12(4)2022 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-35214934

RESUMO

This study investigates switching characteristics of the magnesium fluoride (MgFx)-based bipolar resistive random-access memory (RRAM) devices at different operating ambiances (open-air and vacuum). Operating ambiances alter the elemental composition of the amorphous MgFx active layer and Ti/MgFx interface region, which affects the overall device performance. The experimental results indicate that filament type resistive switching takes place at the interface of Ti/MgFx and trap-controlled space charge limited conduction (SCLC) mechanisms is dominant in both the low and high resistance states in the bulk MgFx layer. RRAM device performances at different operating ambiances are also altered by MgFx active layer treatments (air exposure and annealing). Devices show the better uniformity, stability, and a higher on/off current ratio in vacuum compared to an open-air environment. The Ti/MgFx/Pt memory devices have great potential for future vacuum electronic applications.

11.
Micromachines (Basel) ; 12(9)2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34577692

RESUMO

Electroforming-free resistive switching random access memory (RRAM) devices employing magnesium fluoride (MgFx) as the resistive switching layer are reported. The electroforming-free MgFx based RRAM devices exhibit bipolar SET/RESET operational characteristics with an on/off ratio higher than 102 and good data retention of >104 s. The resistive switching mechanism in the Ti/MgFx/Pt devices combines two processes as well as trap-controlled space charge limited conduction (SCLC), which is governed by pre-existing defects of fluoride vacancies in the bulk MgFx layer. In addition, filamentary switching mode at the interface between the MgFx and Ti layers is assisted by O-H group-related defects on the surface of the active layer.

12.
J Microbiol Biotechnol ; 31(1): 130-136, 2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33046677

RESUMO

Persister cell formation and biofilms of pathogens are extensively involved in the development of chronic infectious diseases. Eradicating persister cells is challenging, owing to their tolerance to conventional antibiotics, which cannot kill cells in a metabolically dormant state. A high frequency of persisters in biofilms makes inactivating biofilm cells more difficult, because the biofilm matrix inhibits antibiotic penetration. Fatty acids may be promising candidates as antipersister or antibiofilm agents, because some fatty acids exhibit antimicrobial effects. We previously reported that fatty acid ethyl esters effectively inhibit Escherichia coli persister formation by regulating an antitoxin. In this study, we screened a fatty acid library consisting of 65 different fatty acid molecules for altered persister formation. We found that undecanoic acid, lauric acid, and N-tridecanoic acid inhibited E. coli BW25113 persister cell formation by 25-, 58-, and 44-fold, respectively. Similarly, these fatty acids repressed persisters of enterohemorrhagic E. coli EDL933. These fatty acids were all medium-chain saturated forms. Furthermore, the fatty acids repressed Enterohemorrhagic E. coli (EHEC) biofilm formation (for example, by 8-fold for lauric acid) without having antimicrobial activity. This study demonstrates that medium-chain saturated fatty acids can serve as antipersister and antibiofilm agents that may be applied to treat bacterial infections.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Escherichia coli/efeitos dos fármacos , Ácidos Graxos/farmacologia , Ácidos Láuricos/farmacologia , Infecções Bacterianas , Tolerância a Medicamentos
13.
ACS Appl Mater Interfaces ; 13(23): 27594-27611, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34080410

RESUMO

Understanding the electrochemical behaviors of Ce(III)/Ce(IV) ions is essential for better treatment, separation, and recycling of lanthanide (Ln) and actinide (An) elements. Herein, electrochemical redox behavior and interconversion of Ce(III)/Ce(IV) ions and their recoveries were demonstrated over newly developed thio-terpyridine-functionalized Au-modified carbon paper electrodes in acidic and neutral electrolytes. Cyclic voltammetry and amperometry were performed for the electrodes with and without thio-terpyridine functionalization. Ce oxide nanostructure recovery was successfully conducted by amperometry, and the electrodeposited nanostructured Ce materials were fully characterized by scanning electron microscopy, high-resolution transmission electron microscopy, X-ray diffraction crystallography, and X-ray photoelectron spectroscopy. Geometry optimization and the electronic energy state calculations were conducted by density functional theory at the B3LYP/GENECP level for the complexes of Ce(III) and Ce(IV) ions with the thio-terpyridine in an aqueous state. The present unique results provide valuable information on understanding redox behaviors of Ln and An ions for their recycling and treatment processes.

14.
Nanomaterials (Basel) ; 11(8)2021 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-34443738

RESUMO

ZIF-derivatized catalysts have shown high potential in catalysis. Herein, bean sprout-like Co-TiO2/Ti nanostructures were first synthesized by thermal treatment at 800 °C under Ar-flow conditions using sacrificial ZIF-67 templated on Ti sheets. It was observed that ZIF-67 on Ti sheets started to thermally decompose at around 350 °C and was converted to the cubic phase Co3O4. The head of the bean sprout structure was observed to be Co3O4, while the stem showed a crystal structure of rutile TiO2 grown from the metallic Ti support. Cu sputter-deposited Co-TiO2/Ti nanostructures were also prepared for photocatalytic and electrocatalytic CO2 reduction performances, as well as electrochemical oxygen reaction (OER). Gas chromatography results after photocatalytic CO2 reduction showed that CH3OH, CO and CH4 were produced as major products with the highest MeOH selectivity of 64% and minor C2 compounds of C2H2, C2H4 and C2H6. For electrocatalytic CO2 reduction, CO, CH4 and C2H4 were meaningfully detected, but H2 was dominantly produced. The amounts were observed to be dependent on the Cu deposition amount. Electrochemical OER performances in 0.1 M KOH electrolyte exhibited onset overpotentials of 330-430 mV (vs. RHE) and Tafel slopes of 117-134 mV/dec that were dependent on Cu-loading thickness. The present unique results provide useful information for synthesis of bean sprout-like Co-TiO2/Ti hybrid nanostructures and their applications to CO2 reduction and electrochemical water splitting in energy and environmental fields.

15.
Cell Immunol ; 265(1): 44-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20659730

RESUMO

We describe here a novel real-time cell tracking system which can measure cell migration routes under cell culture condition. This system includes a mini incubator which controls temperature and CO(2) gas flow and a PDMS (polydimethylsiloxane) chip for chemotaxis measurement. The main differences from previous ones are real-timely long-term (24h) tracking for single cell quantitatively, simple and inexpensive constitution of optical parts for illumination and imaging, and compatible to commercial well plate. The tracking principle is to trace cell images for each 0.2s by converting the live cell images to binary images of black and white. Migration results of HUVEC and NCI-H23 cells are obtained respectively using this system. The results are single cell path (x, y) during migration, cell size, migration distance, migration speed, real-time pictures and so on. This system is applicable to all kinds of researches related to cell migration such as cell angiogenesis, chemotaxis, and moreover cancer metastasis.


Assuntos
Ensaios de Migração Celular/métodos , Movimento Celular/fisiologia , Linhagem Celular Tumoral , Ensaios de Migração Celular/instrumentação , Humanos , Neoplasias/patologia
16.
Materials (Basel) ; 13(23)2020 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-33255328

RESUMO

The electrochemical behaviors of rare earth (RE) ions have extensively been studied because of their high potential applications to the reprocessing of used nuclear fuels and RE-containing materials. In the present study, we fully investigated the electrochemical behaviors of RE(III) (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Yb) ions over a Ni sheet electrode in 0.1 M NaClO4 electrolyte solution by cyclic voltammetry between +0.5 and -1.5 V (vs. Ag/AgCl). Amperometry electrodeposition experiments were performed between -1.2 and -0.9 V to recover RE elements over the Ni sheet. The successfully RE-recovered Ni sheets were fully characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and photoluminescence spectroscopy. The newly reported recovery data for RE(III) ions over a metal electrode provide valuable information on the development of the treatment methods of RE elements.

17.
Nat Med ; 25(3): 448-453, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30643289

RESUMO

There has been a striking generational increase in life-threatening food allergies in Westernized societies1,2. One hypothesis to explain this rising prevalence is that twenty-first century lifestyle practices, including misuse of antibiotics, dietary changes, and higher rates of Caesarean birth and formula feeding have altered intestinal bacterial communities; early-life alterations may be particularly detrimental3,4. To better understand how commensal bacteria regulate food allergy in humans, we colonized germ-free mice with feces from healthy or cow's milk allergic (CMA) infants5. We found that germ-free mice colonized with bacteria from healthy, but not CMA, infants were protected against anaphylactic responses to a cow's milk allergen. Differences in bacterial composition separated the healthy and CMA populations in both the human donors and the colonized mice. Healthy and CMA colonized mice also exhibited unique transcriptome signatures in the ileal epithelium. Correlation of ileal bacteria with genes upregulated in the ileum of healthy or CMA colonized mice identified a clostridial species, Anaerostipes caccae, that protected against an allergic response to food. Our findings demonstrate that intestinal bacteria are critical for regulating allergic responses to dietary antigens and suggest that interventions that modulate bacterial communities may be therapeutically relevant for food allergy.


Assuntos
Anafilaxia/microbiologia , Transplante de Microbiota Fecal , Microbioma Gastrointestinal/genética , Hipersensibilidade a Leite/microbiologia , Animais , Clostridiales/genética , Feminino , Hipersensibilidade Alimentar/microbiologia , Vida Livre de Germes , Voluntários Saudáveis , Humanos , Íleo/microbiologia , Lactente , Masculino , Camundongos
18.
JB JS Open Access ; 3(2): e0046, 2018 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-30280133

RESUMO

BACKGROUND: Brachymetatarsia is usually treated by lengthening the metatarsals, but excessive lengthening can be associated with complications. Our technique combines 1-stage step-cut lengthening of the first metatarsal with shortening and/or lengthening of the neighboring metatarsals and/or phalanges. METHODS: Twenty-four feet (15 patients) were treated for first-ray brachymetatarsia. Widely available commercial image-editing software was used to make a preoperative plan for each patient, with emphasis on the creation of a cosmetically satisfying toe-length arc with minimum shortening and lengthening of the affected metatarsals and proximal phalanges. Length gain and percentage increase were also recorded postoperatively. The American Orthopaedic Foot & Ankle Society (AOFAS) hallux metatarsophalangeal-interphalangeal scoring system was used for clinical evaluation. RESULTS: In all 24 feet, smooth parabolas were created at the level of the metatarsal heads and at the toe tips. All patients showed osseous union, and no complications were noted. However, most patients showed mildly restricted range of motion of the first metatarsophalangeal joint. The mean AOFAS score of the hallux significantly improved from 88.3 preoperatively to 98.1 at the latest follow-up (p < 0.001). CONCLUSIONS: One-stage step-cut lengthening of the first metatarsal combined with shortening and/or lengthening of the adjacent metatarsal and phalangeal bones provides excellent cosmetic and functional results. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

19.
Nanoscale ; 9(40): 15314-15322, 2017 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-28820212

RESUMO

A resistive random access memory (RRAM) device with self-rectifying I-V characteristics was fabricated by inserting a silicon nitride (Si3N4) layer between the bottom electrode and solution-processed active material of an iron oxide-graphene oxide (FeOx-GO) hybrid. The fabricated Au/Ni/FeOx-GO/Si3N4/n+-Si memory device exhibited an excellent resistive switching ratio and a rectification ratio higher than 104. In the Au/Ni/FeOx-GO/Si3N4/n+-Si device, resistive switching occurs in both the FeOx-GO and Si3N4 layers separately, resulting in a highly uniform and stable switching performance. The resistive switching from a high resistance state to a low resistance state in the Au/Ni/FeOx-GO/Si3N4/n+-Si device occurs through a trap-assisted tunneling process in the Si3N4 layer, enabled by the FeOx-GO layer which prevents diffusion of the migrating Ni metal into the switching nitride layer. The intrinsic self-rectifying characteristics of our memory devices arise from the asymmetric barriers for electrons tunneling into the traps of the Si3N4 layer which is sandwiched between the top and bottom electrodes having dissimilar work functions. Our study confirmed that integrating a suitable dielectric layer into the conventional RRAM cell is an innovative strategy to simplify the architecture and fabrication process to realize self-rectifying crossbar arrays.

20.
Clin Orthop Surg ; 9(3): 348-354, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28861203

RESUMO

BACKGROUND: While reconstruction of soft tissue defects is the common purpose, surgical reconstructions of upper extremities and lower extremities have different goals in terms of functional and aesthetic outcomes. The purpose of the current study was to compare and analyze differences between reconstructions of upper extremities and lower extremities using an anterolateral thigh (ALT) flap. METHODS: We analyzed 74 patients who underwent reconstructions of upper extremities and lower extremities using an ALT flap from October 2006 to August 2012 (upper extremities, 45 cases; lower extremities, 29 cases). The study focused on the statistical analysis of patient satisfaction according to the donor site of the ALT flap and the timing of a debulking procedure. RESULTS: On the choice of donor site, in the upper extremity reconstruction, flap elevation from the opposite side of the recipient limb was preferred (p = 0.019) because it causes less inconvenience while walking. In the lower extremity reconstruction, flap elevation from the same side of the recipient limb (p = 0.002) was preferred. The debulking procedure performed on the upper extremities at 4 weeks after reconstruction led to better functional results and enhanced patient satisfaction (p = 0.022). In the case of lower extremities, enhanced satisfaction was noted in patients who underwent the procedure at 6 months after reconstruction (p < 0.001). CONCLUSIONS: Elevation of the flap in reconstruction reduced inconvenience when performed on the same side of the recipient limb for lower extremities and on the opposite side for upper extremities. In addition, debulking resulted in better satisfaction when performed 4 weeks postoperatively in the upper extremities and 6 months postoperatively in the lower extremities.


Assuntos
Braço/cirurgia , Perna (Membro)/cirurgia , Retalho Perfurante/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Coxa da Perna/cirurgia , Traumatismos do Braço/etiologia , Traumatismos do Braço/cirurgia , Humanos , Traumatismos da Perna/etiologia , Traumatismos da Perna/cirurgia , Duração da Cirurgia , Satisfação do Paciente
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