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2.
Front Oncol ; 13: 1132972, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37736552

RESUMO

Background: Malnutrition is common in patients undergoing surgery for cancers and is a risk factor for postoperative outcomes. Body composition provides information for precise nutrition intervention in perioperative period for improving patients' postoperative outcomes. Objection: The aim was to determine changes in parameters of body composition and nutritional status of cancer patients during perioperative period. Methods: A total of 92 patients diagnosed with cancer were divided into gastrointestinal and non-gastrointestinal cancer group according to different cancer types. The patients body composition assessed by bioelectrical impedance vector analysis (BIVA) on the day before surgery, postoperative day 1 and 1 day before discharge. The changes between two groups were compared and the correlation between body composition and preoperative serum nutritional indexes was analyzed. Results: The nutritional status of all patients become worse after surgery, and phase angle (PA) continued to decrease in the perioperative period. Fat-free mass (FFM), fat-free mass index (FFMI), skeletal muscle mass (SMM), extracellular water (ECW), total body water (TBW), hydration, and body cell mass (BCM) rise slightly and then fall in the postoperative period in patients with gastrointestinal cancer, and had a sustained increase in non-gastrointestinal patients, respectively (P<0.05). Postoperative body composition changes in patients with gastrointestinal cancer are related to preoperative albumin, pre-albumin, hemoglobin, and C-reactive protein (P<0.05), whereas postoperative body composition changes in patients with non-gastrointestinal cancer are related to age (P<0.05). Conclusions: Significant changes in body composition both in patients with gastrointestinal cancer and non-gastrointestinal cancer during perioperative period are observed. Changes in body composition for the cancer patients who undergoing surgery are related to age and preoperative serum nutrition index.

3.
Trials ; 21(1): 279, 2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-32188478

RESUMO

BACKGROUND: Myopia is increasing in prevalence and is currently recognized as a significant public health issue worldwide, particularly in China. Once myopia develops, appropriate clinical interventions need to be prescribed to slow its progression. Currently, several publications indicate that myopic defocus (MD) retards eye growth and myopia progression. However, no clinical trials have compared the outcomes of different MD spectacle lenses in the same observational group, especially in mainland China. The aim of the present study is to compare the myopia control efficiency of two different MD spectacle lenses: defocus incorporated multiple segments (DIMS) lenses and Apollo progressive addition lenses (PALs). METHODS: The trial is designed as a 3-year, prospective, randomized, multicenter clinical trial of schoolchildren treated with DIMS lenses and PALs. A total of 600 Chinese primary school children aged 6-12 years will be recruited, and each group is intended to include 300 subjects. The inclusion criteria are myopia between - 1.00 and - 5.00 diopters and astigmatism ≤ 1.50 diopters. The follow-up time points will be 1 month (m), 3 m, 6 m, 12 m, 18 m, 24 m, 30 m, and 36 m. The primary outcome will be determined by the difference between the two groups in cycloplegic spherical equivalent refraction between baseline and the last follow-up visit. The secondary outcome is the axial length, and the exploratory outcomes include ocular biometric measures, peripheral refraction, binocular vision, accommodation, compliance, and the results of questionnaires related to wearing experiences. DISCUSSION: The present study will be the first randomized controlled trial in myopic primary school children treated with DIMS lenses and PALs in China. The results will indicate whether and how much different MD mechanisms retard myopia progression and axial elongation. In addition, the comparison will provide information on the clinical efficacy and safety of DIMS lenses and PALs, including information related to wearing experiences and visual function. TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR), ChiCTR1900025645. Registered on 3 September 2019. http://www.chictr.org.cn/showproj.aspx?proj=42927.


Assuntos
Progressão da Doença , Óculos/classificação , Miopia/terapia , Acomodação Ocular , Criança , China/epidemiologia , Olho/fisiopatologia , Óculos/efeitos adversos , Feminino , Seguimentos , Humanos , Masculino , Estudos Multicêntricos como Assunto , Miopia/epidemiologia , Miopia/patologia , Prevalência , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Refração Ocular , Resultado do Tratamento , Visão Binocular
4.
ACS Appl Mater Interfaces ; 11(40): 37051-37059, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31465197

RESUMO

The development of highly sensitive wearable and foldable pressure sensors is one of the central topics in artificial intelligence, human motion monitoring, and health care monitors. However, current pressure sensors with high sensitivity and good durability in low, medium, and high applied strains are rather limited. Herein, a flexible pressure sensor based on hierarchical three-dimensional and porous reduced graphene oxide (rGO) fiber fabrics as the key sensing element is presented. The internal conductive structural network is formed by the rGO fibers which are mutually contacted by interfused or noninterfused fiber-to-fiber interfaces. Thanks to the unique structures, the sensor can show an excellent sensitivity from low to high applied strains (0.24-70.0%), a high gauge factor (1668.48) at an applied compression of 66.0%, a good durability in a wide range of frequencies, a low detection limit (1.17 Pa), and anultrafast response time (30 ms). The dominated mechanism is that under compression, the slide of the graphene fibers through the polydimethylsiloxane matrix reduces the connection points between the fibers, causing a surge in electrical resistance. In addition, because graphene fibers are porous and defective, the change in geometry of the fibers also causes a change in the electrical resistance of the composite under compression. Furthermore, the interfused fiber-to-fiber interfaces can strengthen the mechanical stability under 0.01-1.0 Hz loadings and high applied strains, and the wrinkles on the surface of the rGO fibers increased the sensitivity under tiny loadings. In addition, the noninterfused fiber-to-fiber interfaces can produce a highly sensitive contact resistance, leading to a higher sensitivity at low applied strains.

5.
Materials (Basel) ; 12(3)2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30704131

RESUMO

Micro-light-emitting diodes (micro-LEDs) are the key to next-generation display technology. However, since the driving circuits are typically composed of Si devices, numerous micro-LED pixels must be transferred from their GaN substrate to bond with the Si field-effect transistors (FETs). This process is called massive transfer, which is arguably the largest obstacle preventing the commercialization of micro-LEDs. We combined GaN devices with emerging graphene transistors and for the first-time designed, fabricated, and measured a monolithic integrated device composed of a GaN micro-LED and a graphene FET connected in series. The p-electrode of the micro-LED was connected to the source of the driving transistor. The FET was used to tune the work current in the micro-LED. Meanwhile, the transparent electrode of the micro-LED was also made of graphene. The operation of the device was demonstrated in room temperature conditions. This research opens the gateway to a new field where other two-dimensional (2D) materials can be used as FET channel materials to further improve transfer properties. The 2D materials can in principle be grown directly onto GaN, which is reproducible and scalable. Also, considering the outstanding properties and versatility of 2D materials, it is possible to envision fully transparent micro-LED displays with transfer-free active matrices (AM), alongside an efficient thermal management solution.

6.
ACS Appl Mater Interfaces ; 10(41): 35503-35509, 2018 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-30246521

RESUMO

Recently, various piezoresistive composites with good flexibility have been developed as sensing materials for flexible strain sensors (FSSs). External forces will be applied to strain sensors when they are used in some circumstances such as wrist bending, etc. However, conventional flexible composites may fail upon being subjected to external forces since they have low strength and are unable to protect the inner vulnerable structure of flexible sensors. In this work, the reduced graphene oxide-coated glass fabric (RGO@GF)/silicone composite is fabricated and used to make high-performance structural flexible strain sensors. The composite is not only flexible and sensitive to strain, but also exhibits the high tensile strength needed to maintain the structural integrity of the flexible strain sensor. Silicone resin and GF are employed to provide flexibility and high strength, respectively. By coating RGO on the surface of GF, the nonconductive GF becomes conductive, which renders the piezoresistive behavior and strain-sensing ability to the RGO@GF/silicone composite. The as-prepared structural flexible sensor not only possesses a good strain sensitivity with a gauge factor of around 113, which is much higher than that of typical strain sensors based on metals, but can also maintain its structural integrity until the applied external force is over 800 N, while the conventional flexible strain sensor fails upon being subjected to an external force of only 5 N. Moreover, the as-prepared structural FSS is applied to monitor wrist movement and breathing to demonstrate its applicability. Overall, the RGO@GF/silicone composite exhibits great potential as a sensing material for structural FSSs for wrist movement, etc.

7.
Nanotechnology ; 29(36): 365301, 2018 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-29901454

RESUMO

Chemical vapor deposited graphene suffers from two problems: transfer from metal catalysts to insulators, and photoresist induced degradation during patterning. Both result in macroscopic and microscopic damages such as holes, tears, doping, and contamination, translated into property and yield dropping. We attempt to solve the problems simultaneously. A nickel thin film is evaporated on SiO2 as a sacrificial catalyst, on which surface graphene is grown. A polymer (PMMA) support is spin-coated on the graphene. During the Ni wet etching process, the etchant can permeate the polymer, making the etching efficient. The PMMA/graphene layer is fixed on the substrate by controlling the surface morphology of Ni film during the graphene growth. After etching, the graphene naturally adheres to the insulating substrate. By using this method, transfer-free, lithography-free and fast growth of graphene realized. The whole experiment has good repeatability and controllability. Compared with graphene transfer between substrates, here, no mechanical manipulation is required, leading to minimal damage. Due to the presence of Ni, the graphene quality is intrinsically better than catalyst-free growth. The Ni thickness and growth temperature are controlled to limit the number of layers of graphene. The technology can be extended to grow other two-dimensional materials with other catalysts.

8.
J Mater Chem B ; 6(6): 896-902, 2018 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32254369

RESUMO

Inspired by biological cilia, a highly flexible dual-mode electronic cilia (EC) sensor is fabricated from graphene-coated magnetic cilia arrays. Polydimethylsiloxane is used as a matrix to make the artificial cilia flexible while Co particles are used to endow the cilia with magnetic properties and graphene coating is employed to make the cilia conductive. The EC-based sensor shows a high sensitivity of 0.4% Pa-1 for a pressure of 0-100 Pa and a low detection limit of 0.9 Pa. The responsive behavior of the EC-based sensor is highly stable in a wide frequency range of 0.1-10 Hz up to 10 000 cycles. Meanwhile, the magnetic field sensitivity of the EC sensor is around 12.08 T-1 for a magnetic field intensity of 150-160 mT. Consequently, the EC sensor is successfully applied in blood pulse monitoring, pressure and magnetic field switching, and visualized pressure and magnetic field detection. Due to its high sensitivity, high durability and dual-mode responsiveness, the flexible EC sensor goes far beyond the capability of human skin, and is believed to have great potential in healthcare, robotics, e-skin and smart surgical tools, etc.

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