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121.
Tomasz Charytoniuk Klaudia Sztolsztener Patrycja Bielawiec Adrian Chabowski Karolina Konstantynowicz-Nowicka Ewa Harasim-Symbor 《International journal of molecular sciences》2022,23(4)
It is known that metabolic disturbances, including obesity, predispose to an increased incidence of cardiovascular diseases. Elevated consumption of dietary fat results in intramyocardial accumulation of lipids and their biologically active derivatives, which can disrupt the contractile function of the heart, its metabolism, and intracellular signaling pathways. Therefore, alternative methods, such as phytocannabinoids, are being sought for the treatment of obesity-related effects. In a model of rodent obesity (seven weeks of high-fat-diet (HFD) regime), we used cannabidiol—CBD therapy (intraperitoneal injections for 14 days; 10 mg/kg). High-performance and gas-liquid chromatographies were applied in order to determine sphingolipids in the heart and plasma as well as Western blotting for protein expression. Two-week CBD administration significantly inhibited the de novo ceramide synthesis pathway in the heart of HFD fed rats by lowering sphinganine and sphinganine-1-phosphate contents. The above reductions were accompanied by markedly diminished expressions of myocardial serine palmitoyltransferase 1 and 2 as well as ceramide synthase 5 and 6 in the HFD group with 2-week CBD treatment. To our knowledge, this research is the first that reveals unknown effects of CBD treatment on the heart, i.e., amelioration of de novo ceramide synthesis pathway in obese rats. 相似文献
122.
López Steven R.; Lara Ma. del Carmen; Kopelowicz Alex; Solano Susana; Foncerrada Hector; Aguilera Adrian 《Canadian Metallurgical Quarterly》2009,77(4):763
The authors developed and tested a 35-min psychoeducational program with the goal of increasing Spanish-speaking persons’ literacy of psychosis. The program uses popular cultural icons derived from music, art, and videos, as well as a mnemonic device—La CLAve (The Clue)—to increase (a) knowledge of psychosis, (b) efficacy beliefs that one can identify psychosis in others, (c) attributions to mental illness, and (d) professional help-seeking. Assessments were conducted before and after administering the program to both community residents (n = 57) and family caregivers of persons with schizophrenia (n = 38). For community residents, the authors observed increases across the 4 domains of symptom knowledge, efficacy beliefs, illness attributions, and recommended help-seeking. For caregivers, increases were observed in symptom knowledge and efficacy beliefs. La CLAve is a conceptually informed psychoeducational tool with a developing empirical base aimed at helping Spanish-speaking Latinos with serious mental illness obtain care in a timely manner. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
123.
Biofuels are set to play an important role in the future strategy of automotive fuel suppliers, and therefore the study of using alcohols in spark ignition engines has become a necessity. A simple thermodynamic model was developed for calculating air–fuel mixture parameters for port injection engines fueled with gasoline–isobutanol blends, and theoretical results were compared to experimental values. For simulating the evaporation process, gasoline was considered a mixture of four components, with isobutanol added in different proportions. As all engine components are at ambient temperature during cold starts, mixture formation was considered an adiabatic process, with the fuel breaking up into droplets and evaporating, thus resulting in a temperature drop. A port injection engine fitted to a passenger car was used to validate the model for calculating air–fuel mixture parameters. 相似文献
124.
Staub Adrian; Grant Margaret; Clifton Charles Jr.; Rayner Keith 《Canadian Metallurgical Quarterly》2011,37(5):1326
In this brief rejoinder, we respond to Farmer, Monaghan, Misyak, and Christiansen (2011). We argue that the data still do not support the claim that reading time is affected by the phonological typicality of a word for its part of speech. We also question Farmer et al.'s claim that interleaving syntactic structures in an experiment modifies grammatically based syntactic expectations. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
125.
Adrian J. Lee 《Reliability Engineering & System Safety》2011,96(8):900-911
Passenger screening at aviation security checkpoints is a critical component in protecting airports and aircraft from terrorist threats. Recent developments in screening device technology have increased the ability to detect these threats; however, the average amount of time it takes to screen a passenger still remains a concern. This paper models the queueing process for a multi-level airport checkpoint security system, where multiple security classes are formed through subsets of specialized screening devices. An optimal static assignment policy is obtained which minimizes the steady-state expected amount of time a passenger spends in the security system. Then, an optimal dynamic assignment policy is obtained through a transient analysis that balances the expected number of true alarms with the expected amount of time a passenger spends in the security system. Performance of a two-class system is compared to that of a selective security system containing primary and secondary levels of screening. The key contribution is that the resulting optimal assignment policies increase security and passenger throughput by efficiently and effectively utilizing available screening resources. 相似文献
126.
Adrian K. Clear Thomas Holland Simon Dobson Aaron Quigley Ross Shannon Paddy Nixon 《Pervasive and Mobile Computing》2010,6(5):575-589
Pervasive systems are large-scale systems consisting of many sensors capturing numerous types of information. As this data is highly voluminous and dimensional, data analysis tasks can be extremely cumbersome and time-consuming. Enabling computers to recognise real-world situations is an even more difficult problem, involving not only data analysis, but also consistency checking. Here we present Situvis, an interactive visualisation tool for representing sensor data and creating higher-level abstractions from the data. This paper builds on previous work, Clear et al. (2009) [8] through evolved tool functionality and an evaluation of Situvis. A user-trial consisting of 10 participants shows that Situvis can be used to complete the key tasks in the development process of situation specifications in over 50% less time than an improvised alternative toolset. 相似文献
127.
Adrian Postelnicu 《International Journal of Heat and Mass Transfer》2009,52(11-12):2466-2470
The onset of convection in a horizontal layer filled with a fluid-saturated porous medium is studied in this paper. On the lower wall there is an exothermic surface reaction, described by the Arrhenius kinetics, while the upper wall is subjected to uniform temperature and concentration. The problem, cast in dimensionless form, is governed by three dimensionless parameters pertaining to the exothermic reaction and the Lewis number. Once the basic state is solved, a linearized stability analysis is then performed and the resulting eigenvalue problem is solved using a conventional shooting method. One determines numerically the critical Rayleigh and wave numbers at the onset of convection, for various values of the problem parameters. 相似文献
128.
Law S. Edward Marchant John A. Bailey Adrian G. 《Industry Applications, IEEE Transactions on》1985,(3):685-693
Fluorescent tracer studies experimentally quantified the spatial distribution of droplet mass transfer and charge transfer characterizing three modes of electrostatic pesticide spraying onto barley-weed-soil target arrays. Droplet charging in the 1.5-4.5 mC/kg range provided significant deposition increases on all plant surfaces while beneficially reducing residues on underlying soil. With the intense space-charge spray clouds utilized (e.g., 10 μC/m3 ), externally applied driving fields as great as 37 kV/m provided no significant deposition increases but instead exacerbated gaseous charge exchange between the spray cloud and the target via undesirable leaf-tip coronas. Nonuniformity characterized deposition of both uncharged and charged sprays throughout the target array, with no improvement provided by spray-entrainment air velocities as great as 2 m/s. Results will guide prototype design by establishing the relative importance of the space charge, the applied field, and the aerodynamic force components for selectively targeting specific sites within living-plant arrays. 相似文献
129.
A new analytical method has been developed for the quantification of polybrominated diphenyl ethers (PBDEs) in human adipose tissue samples. After Soxhlet extraction and a cleanup procedure using two successive solid-phase extraction cartridges containing acid silica and acid silica: neutral silica:deactivated basic alumina (from top to bottom), detection can been achieved by narrow-bore (0.10-mm i.d.) capillary gas chromatography/electron impact low-resolution mass spectrometry using a large-volume injection technique. Using narrow-bore capillaries, it is possible to analyze complex mixtures in a short time (up to 10 min), saving 50% or more of the analysis time of conventional columns while maintaining a similar resolution power. The method allows the determination of five major PBDE congeners (BDE 28, 47, 99, 100, and 153) at concentrations below 1 ng/g lipid weight. Detection limits in the selected ion mode varied between 0.05 and 0.30 ng/g lipid weight, depending on the degree of bromination. The sensitivity of this method can compete with low-resolution mass spectrometry with electron capture ionization, while a much better selectivity is obtained. Levels of PBDEs in 20 Belgian human adipose tissue samples ranged between 2.18 and 11.70 ng/g lipid weight and were similar to previously reported values from Europe. 相似文献
130.
Physical modelling of solute transport in porous media: evaluation of an imaging technique using UV excited fluorescent dye 总被引:1,自引:0,他引:1
The development and evaluation of a 2-dimensional physical model, which is designed to assist in the characterisation of complex solute transport problems in porous media, is described. The laboratory model is a transparent 2-dimensional porous media of nominal thickness and uses a non-invasive imaging technique in conjunction with a fluorescent dye tracer (sodium fluorescein) to monitor solute movements. Under ultraviolet (UV) illumination the dye emits visible light which is imaged by a CCD (Charge Coupled Device) camera. The image is processed to estimate the 2-dimensional distribution of tracer concentrations. The system can successfully model a simple contaminant plume within a homogenous porous matrix constructed from glass beads (60-100 microm). Experimental results show that transverse dispersion coefficient was 3.9 x 10(-10) m2/s when sodium fluorescein transported in porous matrix with a walter velocity of 5.71 x 10(-6) m/s. The low transverse dispersion coefficient suggests that the molecular diffusion of solute cannot be neglected under low velocity of the water. The advantages of using UV rather than an ordinary light system are a reduction in noise and experimental errors. Errors due to light dispersion within the model are shown to be negligible for the current model. Since contaminant with aromatic rings are usually fluorescent and biological samples can be labelled by fluorescent dye, this imaging technique using UV excited fluorescent dye will be used to investigate biodegradation process in porous media. 相似文献