Gel Immersion Method Research Articles

Modified gel immersion method during endoscopic ultrasonography and injection sclerotherapy for esophageal varices.

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Low-pressure endoscopy using the gel immersion method facilitates endoscopic reduction of a Morgagni hernia

Low-pressure endoscopy using the gel immersion method facilitates endoscopic reduction of a Morgagni hernia

Endoscopic cyanoacrylate injection with gel immersion method improved the visual field in profuse gastric variceal hemorrhage.

Endoscopic cyanoacrylate injection is recommended for gastric variceal hemorrhage (GVH) as a means of achieving urgent endoscopic hemostasis [1] [2]. However, it can sometimes be technically difficult to secure the visual field because GVH produces a large amount of blood and bloody clots immediately fill the fundus. Gel immersion endoscopy (GIE) is useful for identification of the gastrointestinal bleeding point as it offers a secure visual field [3] [4] [5]. We report a case of successful hemostasis for GVH using cyanoacrylate injection under GIE ([Video 1]).

Efficacy of gel immersion endoscopic ultrasonography for delineating the duodenal papilla and pancreatobiliary ducts: A retrospective study with video

ObjectivesEndoscopic ultrasonography is an important examination for periampullary diseases. The duodenum is filled with water to ensure a clear image and distend the duodenal wall without burying the papilla within duodenal folds; however, peristalsis frequently makes it difficult to maintain water within the duodenum. The gel immersion method (intestine is filled with viscosity gel) has recently been attracting attention. We evaluated the usefulness of using this method for endoscopic ultrasonography to detect and delineate the major duodenal papilla.MethodsFifty‐nine consecutive patients who underwent gel immersion‐endoscopic ultrasonography between February and March 2021 were included retrospectively. The papilla was observed by filling the duodenum with clear viscosity gel. Outcomes were the rate of duodenal distention, delineation rates of the papilla, the time required for delineation, volume of the gel used, and adverse events.ResultsDuodenal distention was excellent, good, and poor in 58%, 34%, and 7% of cases, respectively. The delineation rates of the papilla in the axial and longitudinal views were 98% and 66%, respectively. The median time required to delineate the papilla in each view was 3.1 (range, 1.0–1.4) and 7.9 (1.9–28.6) min; the median volume of the gel used was 80 (30–150) ml and 100 (50–200) ml, respectively. No adverse events were noted.ConclusionsGel immersion‐endoscopic ultrasonography provided sufficient duodenal distention, leading to high rates of detection and delineation of the papilla using a small volume of gel within a short time. This method may be useful for the evaluation of the ampullary region.

Submarine volcanic eruption of esophageal varices induced by failed variceal ligation and identified by the gel immersion method.

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Successful removal of a toothpick penetrating the sigmoid colon by low-pressure endoscopy using the gel immersion method.

Successful removal of a toothpick penetrating the sigmoid colon by low-pressure endoscopy using the gel immersion method.

Conversion from conventional esophageal endoscopic submucosal dissection to the gel immersion method.

Conversion from conventional esophageal endoscopic submucosal dissection to the gel immersion method.

Low-pressure endoscopy using the gel immersion method facilitates endoscopic variceal ligation of ruptured esophageal varices.

Low-pressure endoscopy using the gel immersion method facilitates endoscopic variceal ligation of ruptured esophageal varices.

Endoscopic ultrasound examination of the intrapancreatic pancreatobiliary ducts using the gel immersion method in patients with periampullary duodenal diverticula.

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ID: 3518653 UTILITY OF GEL IMMERSION METHOD FOR TREATING MASSIVE COLONIC DIVERTICULAR BLEEDING

In Asia, right-sided diverticular bleeding is more common than that of the left side. It often causes massive bleeding and difficulties in identifying the stigmata of recent hemorrhage (SRH) of colonic diverticular bleeding (CDB). This case series demonstrates the efficacy of the gel immersion method using OS-1 Jelly in patients with CDB.

Utility of the Gel Immersion Method for Treating Massive Colonic Diverticular Bleeding

Background/AimsIn Asia, right-sided diverticular bleeding is more common than that of the left side. It often causes massive bleeding and difficulties in identifying the stigmata of recent hemorrhage (SRH) of colonic diverticular bleeding (CDB). This case series demonstrates the efficacy of the gel immersion method using OS-1 Jelly (Otsuka Pharmaceuticals Factory, Tokushima, Japan) in patients with CDB. MethodsThis retrospective case series analyzed data of patients with CDB who underwent the gel immersion method from April 2016 to February 2020 at St. Luke’s International Hospital, Japan. All patients diagnosed with CDB who underwent the gel immersion method were included. We collected data on the site of bleeding, identification of SRH, and efficacy of the method from the electronic medical records. ResultsA total of 9 patients (including 7 with right-sided CDB) underwent gel immersion method and were included in this study. SRH were successfully found in 66.7% (6/9) of patients. Moreover, effective hemostasis was achieved in 85.7% (6/7) of patients with right-sided CDB. There were no adverse events. ConclusionsThe gel immersion method was found to be effective, especially for massive right-sided CDB.

Influence of Annealing Temperature on the Performance of Lu₂O₃:Eu³⁺ Nanowire Arrays Synthesized by Sol–Gel Method Using AAO Template

Lu <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> :Eu <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3+</sup> nanowire arrays were synthesized by the sol-gel immersion method using anodic aluminum oxide (AAO) templates. The influence of annealing temperature on the morphology, crystallinity, luminescence, and transmittance of the Lu <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> :Eu <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3+</sup> nanowire arrays in the AAO templates was studied. The results show that the nanowires in the AAO templates are dense and orderly. Their diameters are uniform and defined by the templates. As annealing temperature increases from 500 °C to 900 °C, the shape of the nanowires remains substantially unchanged, but the crystallinity is greatly improved. When the annealing temperature reaches 1000 °C, the AAO template begins to crystallize and the samples begin to deform or even crack. In view of the fact that a scintillation screen for X-ray imaging requires not only high luminous intensity but also high transparency, no deformation, and no crack, the suitable annealing temperature for synthesizing the screen of a Lu <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> :Eu <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3+</sup> nanowire array in the AAO template was obtained.

Structural, optical, and electrical evolution of sol–gel-immersion grown nickel oxide nanosheet array films on aluminium doping

We developed aluminium (Al)-doped nickel oxide (NiO) nanosheet arrays film on the indium-doped tin oxide (ITO) substrate via sol–gel immersion method using nickel nitrate hexahydrate and aluminium nitrate nonahydrate as precursor and dopant materials, respectively. The Al-doping concentrations were varied from 0 to 2 at.%. Uniform Al-doped NiO nanosheet array films were observed on the substrate; the denser and smaller size of the NiO nanosheets were obtained at higher Al-doping concentrations. The growth mechanism was proposed. The crystallinity of Al-doped NiO nanosheet deteriorated at higher doping concentration. Meanwhile, the crystallite size, lattice parameter, and interplanar spacing were reduced with the doping quantity. The compressive strain, tensile stress, dislocation density, and band gap of the Al-doped NiO upsurged at higher doping concentration. The current–voltage measurement results revealed that the resistivity increased after the doping process up to 2 at.%. The Raman spectra showed that the doped samples exhibit blue-shift and decreased intensity of the Raman peaks.

Improved DSSC photovoltaic performance using reduced graphene oxide–carbon nanotube/platinum assisted with customised triple-tail surfactant as counter electrode and zinc oxide nanowire/titanium dioxide nanoparticle bilayer nanocomposite as photoanode

In this work, reduced graphene oxide (rGO) was produced from graphene oxide (GO) by a reduction process, which utilised hydrazine hydrate as reducing agent. GO was initially synthesised by electrochemical exfoliation assisted with customised triple-tail sodium 1,4-bis(neopentyloxy)-3-(neopentyloxycarbonyl)-1,4-dioxobutane-2-silphonate (TC14) surfactant. The produced TC184-rGO solution was subsequently hybridised with multiwalled carbon nanotubes (MWCNTs) from waste palm oil. The produced TC14-rGO and TC14-rGO/MWCNTs hybrid solution was fabricated as thin films by spray coating method. Afterwards, Pt nanoparticle (NP) coating was fabricated. The films were used as counter electrode (CE) for dye-sensitised solar cell (DSSC) application. Three other CEs, namely TC14-rGO, TC14-rGO/MWCNTs hybrid and TC14-rGO/Pt hybrid, were fabricated for comparison. Zinc oxide nanowire (NWR)/titanium dioxide nanoparticle (NP) bilayer was utilised as photoanode and fabricated via sol–gel immersion and squeegee method. Solar simulator measurement showed that the highest DSSC performance was exhibited by TC14-rGO/MWCNTs/Pt hybrid, which presented an energy conversion efficiency, open-circuit voltage, short-circuit-current density and fill factor of 0.0842%, 0.608 V, 0.285 mA/cm2 and 0.397, respectively. The combination of TC14-rGO/MWCNTs/Pt hybrid CE and ZnO NWR/TiO2 NP bilayer photoanode improved the DSSC performance due to the large surface area of TC14-rGO and MWCNTs, the high electrical conductivity of MWCNTs and the high quality and less agglomeration of thin rGO film assisted with triple-tail TC14 surfactant. The ZnO NWR/TiO2 NP bilayer photoanode also demonstrated a large surface area that can optimally adsorb dye molecules and increase the photo-exciton electrons, which further improve the DSSC performance.

Structural modification of ZnO nanorod array through Fe-doping: Ramification on UV and humidity sensing properties

Iron (Fe)-doped zinc oxide (ZnO) nanotip arrays (FZO) were prepared using low temperature sol–gel immersion method. The X-ray diffraction analysis reveals that the crystallite size reduces from 30.7 to 28.3 nm after doped with Fe. Besides, it is perceived that the lattice strain metamorphoses from tensile to compressive strain after doping with value of -0.23%. Field emission scanning electron microscopy images show that the Fe doping induced a significant modification to the ZnO structure; transforming the structure from rod-like to tip-like structure. The current–voltage measurement results indicate that the FZO film has good electrical properties with resistance value of 12.34 MΩ. The FZO is also capable of performing well as UV and humidity sensors. This study points out that FZO films are suitable for multifunctional uses particularly for UV and humidity sensing.

Polymer microfiber coated with ZnO for humidity sensing

A PMMA microfiber that is coated with ZnO is employed as a relative humidity sensor. The PMMA microfiber with a diameter of 60 μm is fabricated by using a direct drawing method from molten PMMA. Then, the fiber is coated with ZnO that is prepared from sol - gel immersion method. There are two types of coating done for this work, namely ZnO nanostructures and nanorods respectively. The experimental setup for the proposed sensor comprises of an amplified spontaneous emission (ASE) light from Erbium-doped filber amplifier (EDFA), sealed chamber and an optical spectrum analyser (OSA). The variation of the output power of the ASE with relative humidity is recorded. It is observed that the output power for PMMA microfiber coated with ZnO nanostructures decreases from -22.43 to -27.87 dBm as the humidity is increased from 50% and 80%. The performance of the proposed sensor is enhanced after being coated with ZnO, for both nanostructures and nanorods. The results show that the sensitivity of the sensor when it is coated with ZnO nanostructures has improved from 0.1191 dBm/% to 0.1791 dBm/%. When ZnO nanorods are coated onto the PMMA fiber, the performances of the proposed fiber further improved with the sensitivity increases to 0.2159 dBm/%. This proposed sensor provides numerous advantages such as higher mechanical strength and low cost of production. In addition, it is highly suitable for continuous monitoring of relative humidity in compact areas.

Modulation of Sn concentration in ZnO nanorod array: intensification on the conductivity and humidity sensing properties

Tin (Sn)-doped zinc oxide (ZnO) nanorod arrays (TZO) were synthesized onto aluminum-doped ZnO-coated glass substrate via a facile sonicated sol–gel immersion method for humidity sensor applications. These nanorod arrays were grown at different Sn concentrations ranging from 0.6 to 3 at.%. X-ray diffraction patterns showed that the deposited TZO arrays exhibited a wurtzite structure. The stress/strain condition of the ZnO film metamorphosed from tensile strain/compressive stress to compressive strain/tensile stress when the Sn concentrations increased. Results indicated that 1 at.% Sn doping of TZO, which has the lowest tensile stress of 0.14 GPa, generated the highest conductivity of 1.31 S cm−1. In addition, 1 at.% Sn doping of TZO possessed superior sensitivity to a humidity of 3.36. These results revealed that the optimum performance of a humidity-sensing device can be obtained mainly by controlling the amount of extrinsic element in a ZnO film.

Reduced graphene oxide/platinum hybrid counter electrode assisted by custom-made triple-tail surfactant and zinc oxide/titanium dioxide bilayer nanocomposite photoanode for enhancement of DSSCs photovoltaic performance

In this work, custom-made triple-tail sodium 1,4-bis(neopentyloxy)-3-(neopentyloxycarbonyl)-1,4-dioxobutane-2-silphonate (TC14) surfactant was used to assist exfoliation through electrochemical method for synthesis of graphene oxide (GO). A commercially available single-tail sodium dodecyl sulphate (SDS) surfactant was also utilised for comparison. Both synthesised GOs were reduced to produce reduced GO (rGO), which was fabricated into thin films through spray coating. The rGO thin film assisted by TC14 surfactant (TC14-rGO) with Pt nanoparticles was hybridised to improve electrical conductivity. The five different fabricated thin films were TC14-GO, TC14-rGO, SDS-rGO, Pt and TC14-rGO/Pt hybrid, which were used in dye-sensitised solar cells (DSSCs) as counter electrode (CE). Zinc oxide nanorods/titanium dioxide (ZnO NRs/TiO2 bilayer) was used as photoanode and fabricated through a simple sol–gel immersion and squeegee method. Based on solar simulator measurement, TC14-rGO/Pt hybrid CE thin film exhibited the highest energy conversion efficiency of approximately 0.044% with the Voc, Jsc and FF values of approximately 0.618 V, 0.163 mA/cm2 and 0.387, respectively, compared with other fabricated CE materials. The combination of TC14-rGO/Pt hybrid CE and ZnO NRs/TiO2 bilayer photoanode enhanced the DSSCs photovoltaic performance because of the high conductivity, low oxygen content, high quality and less agglomeration of thin rGO films as a result of improved exfoliation by triple-tail TC14 surfactant.

Facile construction of the aerogel/geopolymer composite with ultra-low thermal conductivity and high mechanical performance.

In this work, we have successfully prepared a lightweight, highly hydrophobic and superb thermal insulating aerogel/geopolymer composite by a sol–gel immersion method. After silica aerogel was impregnated, the composite exhibited nano-porous structures. Moreover, scanning electron microscopy observations revealed that the aerogel particles were tightly anchored on the geopolymer surface. With several excellent properties (bulk density: 306.5 g cm−3, thermal conductivity: 0.0480 W m−1 K−1 and maximum compressive strength: 0.79 MPa) the as-prepared composite shows great potential to be applied in the thermal insulation field.

Fabrication of hierarchical Sn-doped ZnO nanorod arrays through sonicated sol−gel immersion for room temperature, resistive-type humidity sensor applications

Hierarchical tin (Sn)-doped zinc-oxide (ZnO) nanorod arrays (SZO) were deposited onto Al-doped ZnO-coated glass substrate by using a sonicated sol–gel immersion method for resistive-type humidity sensor applications. X-ray diffraction patterns revealed that the deposited SZO arrays exhibit a wurtzite structure. SZO possessed smaller average diameter, crystallite size, and thickness than the undoped sample did. The SZO film also exhibited compressive strain and tensile stress values of −0.033% and 77MPa, respectively. Our result showed the sensitivity of the SZO based-sensor improved compared with that of the undoped ZnO, with values of 3.41 and 1.41 at 40% to 70% RH and 70% to 90% RH, respectively. The response and recovery times of the SZO based humidity sensor improved to 230 and 30s, respectively. All these results indicated that SZO had high potential for humidity-sensor applications.