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311.
Reductions in air pollutant emission and ambient concentrations of air pollutants, which would occur in Lima when natural gas (NG) is substituted for existing fuels, were estimated. The analysis suggests that current emission inventories under-predict ambient concentrations. Despite the uncertainty in emissions, the analysis also suggests that significant changes in air pollutant concentrations could be achieved with widespread replacement of diesel and gasoline fuels with NG.  相似文献   
312.
The morphology of a melt-quenched crystalline-crystalline diblock copolymer, poly(ε-caprolactone)-block-polyethylene (PCL-b-PE), was studied by small-angle X-ray scattering and transmission electron microscopy. The melting behavior of PCL-b-PE was also investigated by differential scanning calorimetry. The melting temperature of PCL blocks, Tm,PCL, was ca. 55 °C and that of PE blocks was ca. 96 °C. Therefore, the PE block always crystallized first during quenching from the microphase-separated melt into various temperatures Tc below Tm,PCL to yield an alternating structure composed of PE lamellae and amorphous layers (PE lamellar morphology), and subsequently the crystallization of PCL blocks started at Tc after some induction period. The PE lamellar morphology was preserved after the crystallization of PCL blocks at low crystallization temperatures (Tc<30 °C), that is, the PCL block crystallized within the PE lamellar morphology. At high crystallization temperatures (45 °C>Tc>30 °C), on the other hand, the crystallization of PCL blocks destroyed the PE lamellar morphology to result in a new lamellar morphology mainly consisting of PCL lamellae and amorphous layers (PCL lamellar morphology). The PE crystals were fragmentarily dispersed in the PCL lamellar morphology.  相似文献   
313.
Background: Very few papers covering the anticancer activity of azulenes have been reported, as compared with those of antibacterial and anti-inflammatory activity. This led us to investigate the antitumor potential of fifteen 4,6,8-trimethyl azulene amide derivatives against oral malignant cells. Methods: 4,6,8-Trimethyl azulene amide derivatives were newly synthesized. Anticancer activity was evaluated by tumor-specificity against four human oral squamous cell carcinoma (OSCC) cell lines over three normal oral cells. Neurotoxicity was evaluated by cytotoxicity against three neuronal cell lines over normal oral cells. Apoptosis induction was evaluated by Western blot and cell cycle analyses. Results: Among fifteen derivatives, compounds 7, 9, and 15 showed the highest anticancer activity, and relatively lower neurotoxicity than doxorubicin, 5-fluorouracil (5-FU), and melphalan. They induced the accumulation of a comparable amount of a subG1 population, but slightly lower extent of caspase activation, as compared with actinomycin D, used as an apoptosis inducer. The quantitative structure–activity relationship analysis suggests the significant correlation of tumor-specificity with a 3D shape of molecules, and possible involvement of inflammation and hormone receptor response pathways. Conclusions: Compounds 7 and 15 can be potential candidates of a lead compound for developing novel anticancer drugs.  相似文献   
314.
We report herein on the effects of all-trans retinoic acid (ATRA) on two-dimensional (2D) and three-dimensional (3D) cultures of human trabecular meshwork (HTM) cells that were treated with transforming growth factor β2 (TGF-β2). In the presence of 5 ng/mL TGF-β2, the effects of ATRA on the following were observed: (1) the barrier function of the 2D HTM monolayers, as determined by trans-endothelial electrical resistance (TEER) and fluorescein isothiocyanate (FITC) dextran permeability measurements; (2) a Seahorse cellular bio-metabolism analysis; (3) physical properties, including the size and stiffness, of 3D spheroids; (4) the gene expression of extracellular matrix (ECM) molecules, ECM modulators including tissue inhibitor of metalloproteinases (TIMPs), matrix metalloproteinases (MMPs), tight junction (TJ)-related molecules, and endoplasmic reticulum (ER)-stress-related factors. ATRA significantly inhibited the TGF-β2-induced increase in the TEER values and FITC dextran permeability of the 2D monolayers, while an ATRA monotreatment induced similar effects as TGF-β2. A real-time metabolic analysis revealed that ATRA significantly inhibited the TGF-β2-induced shift in metabolic reserve from mitochondrial oxidative phosphorylation to glycolysis in 2D HTM cells, whereas ATRA alone did not induce significant metabolic changes. In contrast, ATRA induced the formation of substantially downsized and softer 3D spheroids in the absence and presence of TGF-β2. The different effects induced by ATRA toward 2D and 3D HTM cells were also supported by the qPCR analysis of several proteins as above. The findings reported here indicate that ATRA may induce synergistic and beneficial effects on TGF-β2-treated 2D- and 3D-cultured HTM cells; those effects varied significantly between the 2D and 3D cultures.  相似文献   
315.
Although the rate of preterm birth has increased in recent decades, a number of preterm infants have escaped death due to improvements in perinatal and neonatal care. Antenatal glucocorticoid (GC) therapy has significantly contributed to progression in lung maturation; however, its potential effects on other organs remain controversial. Furthermore, the effects of antenatal GC therapy on the fetal heart show both pros and cons. Translational research in animal models indicates that constant fetal exposure to antenatal GC administration is sufficient for lung maturation. We have established a premature fetal rat model to investigate immature cardiopulmonary functions in the lungs and heart, including the effects of antenatal GC administration. In this review, we explain the mechanisms of antenatal GC actions on the heart in the fetus compared to those in the neonate. Antenatal GCs may contribute to premature heart maturation by accelerating cardiomyocyte proliferation, angiogenesis, energy production, and sarcoplasmic reticulum function. Additionally, this review specifically focuses on fetal heart growth with antenatal GC administration in experimental animal models. Moreover, knowledge regarding antenatal GC administration in experimental animal models can be coupled with that from developmental biology, with the potential for the generation of functional cells and tissues that could be used for regenerative medical purposes in the future.  相似文献   
316.
This paper describes a novel stair-climbing wheelchair operated by human upper body using lever propelled rotary-legs with posture transition mechanism. The design principle of this wheelchair is to make use of the user's latent upper body capability, with appropriate mechanisms to enable extended functionality of the regular wheelchair without the need of heavy, expensive mechanisms or electric motors. An arm-operated mechanism allows the user to overcome steps and stairs independently without any external power source. The developed wheelchair consists of manual wheels with casters for planar locomotion, which provides capabilities equivalent to a regular manual wheelchair. In addition, the wheelchair has a rotary-legs mechanism based on lever propulsion control for climbing stairs. It also has a passive mechanism powered by gas springs for posture transition to shift the user's center of gravity between two positions for planar locomotion and for stair-climbing. The proposed design consists of only passive components, which makes the wheelchair more compact and lightweight. In this paper we describe in detail the development of this wheelchair and an investigation of how users can climb stairs independently. We also present evaluation experiments with a healthy participant and a dummy to investigate the feasibility of the proposed design.  相似文献   
317.
To elucidate the additive effects of an EP2 agonist, omidenepag (OMD) or butaprost (Buta) on the Rho-associated coiled-coil-containing protein kinase (ROCK) inhibitor, ripasudil (Rip) on adipose tissue, two- or three-dimension (2D or 3D) cultures of 3T3-L1 cells were analyzed by lipid staining, the mRNA expression of adipogenesis-related genes, extracellular matrix (ECM) molecules including collagen (Col) -1, -4 and -6, and fibronectin (Fn), and the sizes and physical properties of 3D organoids, as measured by a micro-squeezer. The results indicate that adipogenesis induced (1) an enlargement of the 3D organoids; (2) a substantial enhancement in lipid staining as well as the expression of the Pparγ, Ap2 and Leptin genes; (3) a significant softening of the 3D organoids, the effects of which were all enhanced by Rip except for Pparγ expression; and (4) a significant downregulation in Col1 and Fn, and a significant upregulation in Col4, Col6, the effects of which were unchanged by Rip. When adding the EP2 agonist to Rip, (1) the sizes of the 3D organoids were reduced substantially; (2) lipid staining was increased (OMD), or decreased (Buta); (3) the stiffness of the 3D organoids was substantially increased in Buta; (4-1) the expression of Pparγ was suppressed (2D, OMD) or increased (2D, Buta), and the expressions of Ap2 were downregulated (2D, 3D) and Leptin was increased (2D) or decreased (3D), (4-2) all the expressions of four ECM molecules were upregulated in 2D (2D), and in 3D, the expression of Col1, Col4 was upregulated. The collective findings reported herein indicate that the addition of an EP2 agonist, OMD or Buta significantly but differently modulate the Rip-induced effects on adipogenesis and the physical properties of 2D and 3D cultured 3T3-L1 cells.  相似文献   
318.
The paper explores the reason why International Search and Rescue Advisory Group (INSARAG) introduced the classification system for international search and rescue (SAR) teams, INSARAG External Classification (IEC), by reviewing the INSARAG’s lessons‐learned process. The past lessons show that there was a need to register qualified SAR teams that meet the operational standards agreed by the international SAR network and to ensure that these qualified teams are ready to respond. The paper also provides some recommendations to improve the system, such as more awareness and support for receiving countries is necessary so that the IEC as a system fully works.  相似文献   
319.
This paper proposes a torque control method for interior permanent magnet synchronous motors (IPMSMs). The proposed method uses state feedback control based on a new n‐t coordinate system and controls the voltage amplitude and phase based on the coordinate system. The t‐axis is a tangent line of the constant voltage ellipse, and the n‐axis is a normal line of the ellipse. The n‐axis current is utilized to place the poles of the transfer function at the desired position and reduce the mutual coupling between the voltage amplitude controller and phase controller. The proposed method realizes a high torque response even under parameter variation for the linear range and over‐modulation range of the inverter, including a 6‐step mode. The effectiveness of the proposed method was verified by simulation and experimental results.  相似文献   
320.
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