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Supercritical carbon dioxide (CO2) has extremely important applications in the extraction of unconventional oil and gas, especially in fracturing and enhanced oil recovery (EOR) technologies. It can not only relieve water resource wastage and environmental pollution caused by traditional mining methods, but also effectively store CO2 and mitigate the greenhouse effect. However, the low viscosity nature of supercritical CO2 gives rise to challenges such as viscosity fingering, limited sand-carrying capacity, high filtration loss, low oil and gas recovery efficiency, and potential rock adsorption. To overcome these challenges, low-rock-adsorption thickeners are required to enhance the viscosity of supercritical CO2. Through research into the literature, this article reviews the solubility and thickening characteristics of four types of polymer thickeners, namely surfactants, hydrocarbons, fluorinated polymers, and silicone polymers in supercritical CO2. The thickening mechanisms of polymer thickeners were also analyzed, including intermolecular interactions, LA-LB interactions, hydrogen bonding, and functionalized polymers, and so on.
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Magnetically and bias current tunable transient photovoltaic (TPV) responses have been investigated in a manganite-based heterojunction composed of a La2/3Ca1/3MnO3 film and an n-type Si substrate at ambient temperature. Under irradiation of 248 nm pulsed laser with 20 ns duration the TPV peak values can be modulated in a range of -125 to 138 mV when the applied magnetic field perpendicular to the interface changes from -6.4 to + 6.4 kOe, and the relative variations (TPV(H) - TPV(0))/TPV(0) reach up to about 1000%. In addition, TPV responses can be also affected by bias current, and the photoresponse peaks change from positive to negative with the currents from -350 to 350 µA. These results indicate that the manganite-based heterojunction can be used for magnetically and electrically tunable ultraviolet photodetectors.
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Lateral photovoltaic effect has been studied in p-La0.67Ca0.33MnO3/n-Si heterojunction. Under illumination of continuous 808 nm laser beam on the film surface, a transient photovoltaic overshoot accompanied with the steady signal was observed when the laser turned off and on. The open-circuit photovoltage had a linear dependence on illuminated position, and the sensitivity reached 0.75 mV mW(-1) mm(-1) for steady value and 6.25 mV mW(-1) mm(-1) for the transient peak value. Especially, an enhancement in position detecting sensitivity was observed when the interface of this heterojunction was irradiated, which were 1.25 mV mW(-1) mm(-1) (steady value) and 26.0 mV mW(-1) mm(-1) (peak value). This work demonstrates a novel way to increase sensitivity for manganite-based position sensitive detectors.
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AIMS: Aerobic training (AT) and resistance training (RT) can reduce blood glucose and type 2 diabetes risk, and increase muscle mass for prediabetes patients. However, the impact of long-term AT and RT on cardiovascular disease (CVD) risk remains unclear. The purpose of this study was to investigate the impact of AT and RT on CVD risk reduction in prediabetes patients. MATERIALS AND METHODS: 248 prediabetes patients were enrolled in this multi-center randomized controlled trial (RCT). Patients were randomly divided into 3 groups: RT (nâ¯=â¯82), aerobic training (AT (nâ¯=â¯83)), and control group (nâ¯=â¯83). Participants in RT and AT groups had moderate RT or AT 3 times a week (150â¯min/week) under supervision in 3 research centers for 24 months. Primary outcome was CVD risk measured by Framingham Risk Score (FRS) and The Chinese 10-year ischemic cardiovascular disease (ICVD) risk assessment tool. Secondary outcomes included in HOMA2-IR, HbA1c, blood pressure and serum lipid profile. RESULTS: Both RT and AT groups experienced a significant reduction in HOMA2-IR, HbA1c, LDL-C, TC, SBP, and DBP at the end of 12 and 24 months. Compared to the control group, Both RT and AT groups had significant reduction of the Chinese 10-year ICVD risk (Pâ¯<â¯0.05), but FRS CVD risk declined significantly only in the AT group (all Pâ¯<â¯0.05). Although FRS CVD risk decreased more in the RT group than in the control group, the difference was not statistically significant. After adjusting for age, gender, statin use, BMI, and WHR, in COX's proportional hazard model, RT (HRâ¯=â¯0.419, Pâ¯=â¯0.037) and AT (HRâ¯=â¯0.310, Pâ¯=â¯0.026) were protective factors for CVD risk in prediabetes patients. 24-month RT and AT decreased respectively 58.1% and 69.0% of CVD risk (10-year ICVD risk assessment) in prediabetes patients. CONCLUSIONS: This study demonstrated that 24-month moderate AT reduces the Chinese 10-year ICVD risk and FRS CVD risk in prediabetes patients. RT groups had significant reduction of CVD risk (10-year ICVD risk assessment) in prediabetes patients. TRIAL REGISTRATION: Clinical trial registration number: NCT02561377. DATE OF REGISTRATION: 24/09/2015.
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Enfermedades Cardiovasculares , Estado Prediabético , Entrenamiento de Fuerza , Glucemia , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/prevención & control , Humanos , Estado Prediabético/diagnóstico , Estado Prediabético/terapia , Factores de RiesgoRESUMEN
INTRODUCTION: A variety of molecular pathways, such as generation of advanced glycation end products, inflammation, and oxidative stress, are involved in the development of diabetic nephropathy (DN). Recently, a protective effect of omega-3 polyunsaturated fatty acids on the kidney has been reported. This study aimed to determine serum docosahexaenoic acid (DHA) level and its association with inflammation factors in patients with DN. MATERIALS AND METHODS: One hundred patients with type 2 diabetic mellitus were divided into 3 groups of non-DN, early DN, and clinical DN, based on 24-hour urinary albumin levels. Hemoglobin A1c, biochemical indicators, ß2-microglobulin, and 24-hour urine albumin levels were assessed. Enzyme linked immunosorbent assay was applied to determine the serum concentrations of DHA, advanced glycation end products, fractalkine, superoxide dismutase, and tumor necrosis factor-α. RESULTS: Lower serum DHA and superoxide dismutase and higher serum ß2-microglobulin and 24-hour urine albumin levels were associated with clinical DN, compared to no DN and early DN. The reductions in serum DHA levels were different among the patients with early and clinical DN, stratified by sex, body mass index, and serum lipid levels. Serum DHA significantly correlated positively with superoxide dismutase and negatively with fractalkine and tumor necrosis factor-α in the patients with DN. CONCLUSIONS: Docosahexaenoic acid may suppress the expression and secretion of fractalkine through inhibiting the tumor necrosis factor-α signaling pathway in DN patients, which improves inflammation and oxidative stress of the kidney, and in turn, delaying the development of DN.
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Diabetes Mellitus Tipo 2/complicaciones , Nefropatías Diabéticas/sangre , Ácidos Docosahexaenoicos/sangre , Mediadores de Inflamación/sangre , Riñón/metabolismo , Adulto , Anciano , Albuminuria/sangre , Albuminuria/diagnóstico , Albuminuria/etiología , Biomarcadores/sangre , Quimiocina CX3CL1/sangre , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/diagnóstico , Nefropatías Diabéticas/diagnóstico , Nefropatías Diabéticas/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estrés Oxidativo , Factor de Necrosis Tumoral alfa/sangreRESUMEN
In this manuscript, we designed and synthesized three core cross-linked micelles (M-5L, P-5L, and P-5D) with redox-responsive disulfide bonds in the core and carrying optically active helical polyisocyanide arms. Their arms were different in the helicity of the main chain and the chirality of the side groups. These micelles showed excellent redox-responsiveness to reducing agent. However, because of the different chiralities of the arms, the three micelles exhibited different performances in drug delivery and controlled release. The M-5L micelle carrying left-handed helical arms showed better therapeutic effect than the other two due to the rapid cell membrane permeability.
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We demonstrate that indium tin oxide nanowires (ITO NWs) and cationic polymer-modified ITO NWs configured in a network format can be used as high performing UV/vis photodetectors. The photovoltage response of ITO NWs is much higher than similarly constructed devices made from tin oxide, zinc tin oxide, and zinc oxide nanostructures. The ITO NW mesh-based devices exhibit a substantial photovoltage (31-100 mV under illumination with a 1.14 mW 543 nm laser) and photocurrent (225-325 µA at 3 V). The response time of the devices is fast with a rise time of 20-30 µs and a decay time of 1.5-3.7 ms when probed with a 355 nm pulsed laser. The photoresponsivity of the ITO NW devices ranges from 0.07 to 0.2 A/W at a 3 V bias, whose values are in the performance range of most commercial UV/vis photodetectors. Such useful photodetector characteristics from our ITO NW mesh devices are attained straightforwardly without the need for complicated fabrication procedures involving highly specialized lithographic tools. Therefore, our approach of ITO NW network-based photodetectors can serve as a convenient alternative to commercial or single NW-based devices.
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We determine the surface enhanced Raman (SER) capability of indium tin oxide nanorods (ITO NRs) whose physical, chemical, and optical properties are precisely and uniformly controlled during synthesis. We demonstrate that the Raman intensities observed from varying concentrations of the pure and mixed molecules of rhodamine 6G and 4',6-diamidino-2-phenylindole are much larger on ITO NRs relative to those measured on commercially available ITO-coated glass or Si. Our efforts signify the first attempt to assess the SER capability of precisely controlled metal oxide NRs and will be highly beneficial to many basic and applied Raman applications requiring exceptional detection sensitivity.