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The photorefractive properties of triphenylamine polymer-based composites with various composition ratios were investigated via optical diffraction, response time, asymmetric energy transfer, and transient photocurrent. The composite consisted of a photoconductive polymer of poly((4-diphenylamino)benzyl acrylate), a photoconductive plasticizer of (4-diphenylamino)phenyl)methanol, a sensitizer of [6,6]-phenyl-C61-butyric acid methyl ester, and a nonlinear optical dye of (4-(azepan-1-yl)-benzylidene)malononitrile. The photorefractive properties and related quantities were dependent on the composition, which was related to the glass transition temperature of the photorefractive polymers. The quantum efficiency (QE) of photocarrier generation was evaluated from the initial slope of the transient photocurrent. Transient photocurrents were measured and showed two unique peaks: one in the range of 10-4 to 10-3 s and the other in the range of 10-1 to 1 s. The transient photocurrents was well simulated (or reproduced) by the expanded two-trapping site model with two kinds of photocarrier generation and recombination processes and two different trapping sites. The obtained photorefractive quantity of trap density was significantly related to the photoconductive parameters of QE.
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BACKGROUND: Quick arterial cannulation is required in pediatric emergency situation, which require effective local anesthesia to avoid withdrawal movement. However, pediatric local anesthesia could be difficult because of withdrawal movement. Jet injectors, which are needleless and provide local anesthesia quickly, could be helpful for pediatric local anesthesia during arterial cannulation. AIMS: This study aimed to examine whether new jet injector "INJEX50" could improve the success rate of local anesthesia for arterial cannulation in pediatric intensive care unit compared with the current standard of care, infiltration using a 26-gauge needle. METHODS: This study was a randomized, double-blind, single-center study. Participants were infants and young children in the pediatric intensive care unit, who required an arterial line. Local anesthesia was performed with either a 26-gauge needle (group C) or INJEX50 (group I) before arterial cannulation. The primary outcome (success of local anesthesia) was the presence of withdrawal movement at the time of skin puncture for arterial cannulation. The secondary outcomes included rescue sedation during arterial cannulation. Data were analyzed using Fisher's exact test and the Mann-Whitney U-test, with values of p < .05 considered statistically significant. RESULTS: Seventy patients were randomly assigned to groups C and I. The local anesthesia success rate in group I (30/35 [86%]) was significantly higher than that in group C (15/35 [43%], odds ratio, 8.00; 95% confidence interval, 2.51-25.5; p = .0005). In conclusion, INJEX50 could improve success rate of local anesthesia for arterial cannulation in pediatric intensive care unit compared with 26-gauge needle.
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The existing methods for the generation of arbitrary vector vortex beams often involve complex optical setups or intricate fabrication methods. In this Letter, we propose a novel, to the best of our knowledge, and simplified approach for the efficient generation of vector vortex beams using a polarization-multiplexed hologram fabricated on an azo-carbazole polymer using a simple double-exposure technique. The hologram generates a vector vortex beam when simply illuminated by a collimated beam and also allows for a seamless traversal across the entire higher-order Poincaré sphere (arbitrary vortex beam generation) just by modulating the polarization of an illuminating beam.
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PURPOSE: The main aim of the current trial was to explore our hypothesis that cooling head wraps lower the core temperature more effectively than ice packs on the head during forced-air warming after pediatric cardiac surgeries. METHODS: This study was a single-center Randomized Controlled Trial. Participants were children with a weight ≤ 10 kg and hyperthermia during forced-air warming after cardiac surgeries. When the core temperature reached 37.5 °C, ice packs on the head (group C) or a cooling head wrap (group H) were used as cooling devices to decrease the core temperature. The primary outcome was the core temperature. The secondary outcomes were the foot surface temperature and heart rate. We measured all outcomes every 30 min for 240 min after the patient developed hyperthermia. We conducted two-way ANOVA as a pre-planned analysis and also the Bonferroni test as a post hoc analysis. RESULTS: Twenty patients were randomly assigned to groups C and H. The series of core temperatures in group H were significantly lower than those in group C (p < 0.0001), and post hoc analysis showed that there was no significant difference in core temperatures at T0 between the two groups and statistically significant differences in all core temperatures at T30-240 between the two groups. There was no difference between the two groups' surface temperatures and heart rates. CONCLUSIONS: Compared to ice packs on the head, head cooling wraps more effectively suppress core temperature elevation during forced-air warming after pediatric cardiac surgery.
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Procedimentos Cirúrgicos Cardíacos , Hipotermia , Humanos , Criança , Temperatura , Gelo , Temperatura Corporal/fisiologia , Unidades de Terapia Intensiva Pediátrica , Hipotermia/prevenção & controleRESUMO
BACKGROUND AND AIM: Transcatheter device closure has become the first treatment option for atrial septal defects (ASD). Surgical ASD closure, although still implemented, is cosmetically inferior to transcatheter closure. This study aimed to evaluate the feasibility as well as short- and long-term clinical outcomes of the right posterolateral minithoracotomy approach for surgical ASD closure. METHODS: In total, 102 consecutive patients underwent posterolateral minithoracotomy for ASD between January 2014 and December 2021 at our center. Early surgical outcomes, cosmetic findings, and skin perception were evaluated over 1 year of postoperative follow-up using a self-satisfaction survey (1: very good, 2: good, 3: normal, 4: not good, 5: bad), Cavendish score, and shoulder joint function (angles of flexion, extension, and abduction). RESULTS: No patient required conversion to median sternotomy. Only one patient required reoperation due to bleeding. Postoperative echocardiography revealed no residual shunt at discharge in all patients. The mean follow-up period was 3.7 years (range: 0.3-7.1 years), during which the questionnaire was answered by 69 of 98 patients who were evaluated after more than 1 year. The mean self-satisfaction survey scores for cosmetic findings and skin perception were 1.3 ± 0.6 and 1.2 ± 0.5, respectively. The Cavendish score was under Grade 1 in all patients. Shoulder flexion and abduction were normal at 180° in all patients, except one, while extension was normal at 50° in all patients, except three. CONCLUSIONS: Our procedure achieved not only good early surgical outcomes but also excellent long-term cosmetic and shoulder function results.
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Comunicação Interatrial , Ombro , Humanos , Resultado do Tratamento , Estudos Retrospectivos , Ombro/cirurgia , Toracotomia/métodos , Comunicação Interatrial/cirurgia , Cateterismo Cardíaco/métodosRESUMO
The radical mechanisms of the thermal degradation of polyamide 66 (PA66) occurring under a vacuum at a temperature range between 80 °C and 240 °C (which includes the temperature of practical applications) were investigated using a spin-trapping electron spin resonance (ST-ESR) technique, as well as FTIR, TG-DTA, and GPC methods. No significant weight loss and no sign of thermal degradation are observed at this temperature range under oxygen-free conditions, but a slight production of secondary amine groups is confirmed by FTIR. GPC analysis shows a small degradation by the main chain scission. ST-ESR analysis reveals two intermediate radicals which are produced in the thermal degradation of PA66: (a) a âCH2- radical generated by main chain scission and (b) a -âCH- radical generated by hydrogen abstraction from the methylene group of the main chain. The ST-ESR result does not directly confirm that a -NH-âCH- radical is produced, although this reaction has been previously inferred as the initiation reaction of the thermal degradation of PA; however, the presence of -âCH- radicals strongly suggests the occurrence of this initiation reaction, which takes place on the α-carbon next to the NH group. The ST-ESR analysis reveals very small levels of reaction, which cannot be observed by common analytical methods such as FTIR and NMR.
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Ince-Gaussian beams, defined as a solution to a wave equation in elliptical coordinates, have shown great advantages in applications such as optical communication, optical trapping and optical computation. However, to ingress these applications, a compact and scalable method for generating these beams is required. Here, we present a simple method that satisfies the above requirement, and is capable of generating arbitrary Ince-Gaussian beams and their superposed states through a computer-generated hologram of size 1 mm2, fabricated on an azocarbazole polymer film. Other structural beams that can be derived from the Ince-Gaussian beam were also successfully generated by changing the elliptical parameters of the Ince-Gaussian beam. The orthogonality relations between different Ince-Gaussian modes were investigated in order to verify applicability in an optical communication regime. The complete python source code for computing the Ince-Gaussian beams and their holograms are also provided.
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BACKGROUND: Tracheal perforation, although rare, is a known late complication of tracheostomy tube placement. CASE PRESENTATION: We present a 7-year-old boy with severe physical and mental disabilities under tracheostomy and long-term mechanical ventilation and steroid therapy who suddenly developed obstructive shock secondary to pneumomediastinum and pneumothorax. Prior bronchoscopy had shown the tip of the tracheostomy tube contacting the posterior tracheal wall, causing ulceration and subsequent tracheal perforation. The perforation was bridged using a cuffed tracheostomy tube, but the patient subsequently died of additional comorbidities. CONCLUSIONS: Our experience suggests that tracheal perforation should be considered when pediatric patients with tracheostomy tubes suddenly develop hypotension.
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Photorefractive (PR) performances are affected by the components of the photoconductor, sensitizer, nonlinear optical dye, and plasticizer. A photoconductor with high hole mobility promises a faster response time, whereas it induces higher photoconductivity, which leads to easy dielectric breakdown. Adding a second electron trap is effective in controlling photoconductivity. In this study, the role of a second electron trap 1,3,5-tri[(3-pyridyl)-phen-3-yl]benzene (TmPyPB) was investigated in a PR composite consisting of a photoconductor of poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] with a high hole mobility, a nonlinear optical chromophore of piperidinodicyanostyrene, a plasticizer of (2,4,6-trimethylphenyl)diphenylamine, and a sensitizer of [6,6]-phenyl C61 butyric acid-methyl ester. The minimum time response with the maximum optical diffraction efficiency and sensitivity was measured at a 1 wt % content of TmPyPB. These results were consistent with the number of charge carriers trapped per unit volume and per unit time N c (cm-3 s-1), which is defined as the ratio between the initial trap density T i (cm-3) and response time τ (s), at a 1 wt % content of TmPyPB. A faster response time of 149 µs, optical diffraction of 24.1% (external diffraction of 4.8%), and a sensitivity of 2746 cm2 J-1 were measured at 50 V µm-1 for the sample with 1 wt % TmPyPB. High loading of 5 wt % TmPyPB led to a large decrease in photoconductivity and effectively suppressed the dielectric breakdown under a stronger electric field, whereas a slower response time with lower diffraction efficiency was observed for optical diffraction.
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An integrated device capable of generating large number of multiplexed optical vortex beams with arbitrary topological charge is considered as one of the crucial requirement for driving information photonics forward. Here we report a simple method for simultaneous generation of 100 multiplexed optical vortex beams from a polymer film of size 1 mm2 and thickness of 30 µm. This is achieved through a combination of computer-generated holography, digital hologram printing and photoisomeric polymers. When the fabricated sample is illuminated with a collimated laser beam, a pre-determined vortex array with arbitrary topological charge is emitted. The polymer film easy to synthesize and exhibits a diffraction efficiency of 30% with a retention period longer than 50 days.
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The XPC protein complex plays a central role in DNA lesion recognition for global genome nucleotide excision repair (GG-NER). Lesion recognition can be accomplished in either a UV-DDB-dependent or -independent manner; however, it is unclear how these sub-pathways are regulated in chromatin. Here, we show that histone deacetylases 1 and 2 facilitate UV-DDB-independent recruitment of XPC to DNA damage by inducing histone deacetylation. XPC localizes to hypoacetylated chromatin domains in a DNA damage-independent manner, mediated by its structurally disordered middle (M) region. The M region interacts directly with the N-terminal tail of histone H3, an interaction compromised by H3 acetylation. Although the M region is dispensable for in vitro NER, it promotes DNA damage removal by GG-NER in vivo, particularly in the absence of UV-DDB. We propose that histone deacetylation around DNA damage facilitates the recruitment of XPC through the M region, contributing to efficient lesion recognition and initiation of GG-NER.
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Absent pulmonary valve syndrome and double-outlet left ventricle are rare congenital anomalies, with, to the best of our knowledge, no cases reported to date. We present the treatment course in a patient with an absent pulmonary valve, double-outlet left ventricle, dextrocardia, hypoplastic right ventricle, valvular aortic stenosis, and bronchomalacia.
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Dupla Via de Saída do Ventrículo Direito , Estenose da Valva Pulmonar , Valva Pulmonar , Transposição dos Grandes Vasos , Humanos , Valva Pulmonar/diagnóstico por imagem , Valva Pulmonar/cirurgia , Valva Pulmonar/anormalidades , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/anormalidades , Estenose da Valva Pulmonar/diagnóstico , Estenose da Valva Pulmonar/diagnóstico por imagem , Dupla Via de Saída do Ventrículo Direito/diagnóstico por imagem , Dupla Via de Saída do Ventrículo Direito/cirurgiaRESUMO
BACKGROUND: Physicians have had to perform numerous extubation procedures during the prolonged coronavirus disease 2019 (COVID 19) pandemic. Future pandemics caused by unknown pathogen may also present a risk of exposure to infectious droplets and aerosols. AIM: This study evaluated the ability of a newly developed aerosol barrier, "Extubation-Aerosol (EA)-Shield" to provide maximum protection from aerosol exposure during extubation via an aerosolised particle count and high-quality visualisation assessments. METHODS: We employed a cough model having parameters similar to humans and used micron oil aerosol as well as titanium dioxide as aerosol tracers. Aerosol barrier techniques employing a face mask (group M) and EA-Shield (group H) were compared. FINDINGS: The primary outcome was the difference in the number of particles contacting the physician's face before and after extubation. The maximum distances of aerosol dispersal after extubation were measured as the secondary outcomes. All aerosolised particles of the two tracers were significantly smaller in group H than in group M (p < 0.05). In addition, the sagittal and axial maximum distances and sagittal areas of aerosol dispersal for 3, 5, and 10 s after extubation were significantly smaller in group H than in group M (p < 0.05). CONCLUSION: This model indicates that EA-Shield could be highly effective in reducing aerosol exposure during extubation. Therefore, we recommend using it as an aerosol barrier when an infectious aerosol risk is suspected.
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PURPOSE: The aim of this study was to compare aerosol exposure with or without an aerosol box in a pressurized/depressurized room during aerosol-generating procedures using an experimental model. METHODS: Cake flour (aerosol model) was expelled from an advanced life support training mannequin. The primary outcome measure was the number of 0.3-10 µm-sized particles at three locations corresponding to the physician, medical staff, and environmental aerosol exposure levels. The aerosol dispersion was visualized using a high-resolution video. The number of expelled particles was measured after artificial coughing during simulated tracheal intubation and extubation in four situations, with or without an aerosol box in a pressurized or depressurized room (≤ 2.5 Pa). RESULTS: The particles arising from tracheal intubation at the three positions in the four groups differed significantly in size (p < 0.05). The sizes of particles arising from extubation at the physicians' and medical staff's faces in the four groups differed significantly in size (p < 0.05). Post hoc analysis showed that the counts of all particles at the three positions were significantly lower in the depressurized room with an aerosol box than in the pressurized room without an aerosol box during tracheal intubation (p < 0.05 at three positions) and extubation (p < 0.05) at the physician's and medical staff's positions). Visual assessments supported these results. CONCLUSION: The aerosol box decreased the exposure of the aerosol to the physician, medical staff, and environment during aerosol-generating procedures in the depressurized room only.
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COVID-19 , Transmissão de Doença Infecciosa do Paciente para o Profissional , Humanos , Intubação Intratraqueal/métodos , Manequins , Aerossóis e Gotículas RespiratóriosRESUMO
The purpose of this study is to investigate the thermo-oxidative degradation behavior of polypropylene (PP) by comparing three types of pristine PP granules (consisting of homopolymer, random copolymer, and block copolymer) with their corresponding oxidized analogues. These analogues were intensely oxidized under oxygen at 90 °C for 1000 h by using the electron spin resonance (ESR) spin trapping method that can detect short-lived radical intermediates during the degradation. The degrees of oxidation could be evaluated by chemiluminescence (CL) intensity, which was related to the concentration of hydroperoxide groups generated in the PP chain. In the pristine PP samples, a small amount of hydroperoxides were found to be formed unintentionally, and their homolysis produces alkoxy radicals, ROâ¢, which then undergo ß-scission to yield chain-end aldehydes or chain-end ketones. These oxidation products continue to take part in homolysis to produce their respective carbonyl and carbon radicals. On the other hand, in the oxidized PP granules, because of their much higher hydroperoxide concentration, the two-stage cage reaction and the bimolecular decomposition of hydroperoxides are energetically favorable. Carbonyl compounds are formed in both reactions, which are then homolyzed to form the carbonyl radical species, â¢C(O)-. PP homopolymer produced the largest amount of carbonyl radical spin adduct; thus, it was found that the homopolymer is most sensitive to oxygen attack, and the presence of ethylene units in copolymers enhances the oxidation resistance of PP copolymers.
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Large-area helix microstructures intended for metamaterials were fabricated using a negative photoresist, SU-8 using a two photon absorption direct laser writing (TPA-DLW). Two types of helix structures were fabricated. One type is those with no neighboring distance. In this case, compact helix structures with radius of 2.5 and 1.0 µm were fabricated. Another type is those with enough neighboring distance. The helix structures with shorter neighboring distance below 6.0 µm were collapsed, whereas those with longer neighboring distance more than 6.5 µm, free-standing helix structures could successfully be built. To stabilize the fabricated free-standing helix microstructures with a 1 µm radius, circular foundations with a radius of 1.3 µm and elevation angle of 10, 12, or 14° were built in advance. The foundation is useful to avoid collapsing the helix microstructures. Due to the useful foundation, over 18,000 helical structures were fabricated in a large area. The fabricated helical structures were coated with silver using an electroless plating method to produce 3D metallic helix structures. Silver coating was measured using a EDX measurement. The obtained helical structures have the potential for metamaterials to control the handedness of a circularly polarized infrared beam.
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The preservation of marine ecosystems is one of the most severe challenges at present. In particular, oil-water separation from oil spills and oily wastewater is important. For this reason, a low-cost, effective, and sustainable polymeric solution is in high demand. In this work, a controlled-wettability membrane for selective separation of oil-water mixtures and emulsions is developed. The nanofibrous membrane is prepared via a facile and cost-effective electrospinning technique using environmentally sustainable materials, such as recycled polyethylene terephthalate and chitosan. The effect of different concentrations of chitosan on the morphology, chemical composition, mechanical properties, wettability, and separation performance of the membrane is evaluated. The membranes exhibited underoil superhydrophobic and underwater superoleophobic behavior, which is essential to perform the selective separation. In fact, the designed filter has competitive antifouling properties (oil intrusion pressure > 45 kPa) and showed high heavy- and light-oil/water separation efficiencies (>95%) both for emulsions and immiscible mixtures.
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BACKGROUND: Epidural tunneling could help with prolonged catheterization and be effective in preventing infection and dislodgement. However, epidural tunneling techniques carry a risk of catheter shear or needlestick injuries. AIMS: This study aimed to examine the safety of our epidural tunneling technique in terms of catheter shear. METHODS: This study was designed as a double-blinded, single-crossover, in vitro study. Each of the operators performed two techniques to create a subcutaneous tunnel. We compared outcomes between the control tunneling technique (group C) and our improved technique (group I). Microscopic findings of catheter shear were assessed as the primary outcome. Secondary outcomes included the tension and displacement required to break the epidural catheter and the frequency of catheter breakage due to catheter shear. Data were analyzed using the Fisher's exact test and Mann-Whitney U test. A p-value of <.05 was considered statistically significant. RESULTS: Ten catheters were assessed in each group. The frequency of catheter shear was 10% in group I and 90% in group C (odds ratio, 0.019; 95% confidence interval [CI], 0.01-0.31; p < .001). The frequency of catheter breakage due to catheter shear was significantly lower in group I (0%) than in group C (80%; p < .001). The mean tension and displacement required to break the catheter were significantly higher in group I than in group C (4.13 ± 0.37 N vs. 3.14 ± 1.00 N; mean difference, 0.99 N; 95% CI, 0.25-1.73 N; p = .013 and 222 ± 59.9 mm vs. 122 ± 77.7 mm; mean difference, 100 mm; 95% CI, 34.1-165 mm; p = .005). CONCLUSIONS: Our improved epidural tunneling technique, which was designed for pediatric cases, could reduce the risk of catheter shear.