There is no effective treatment for recurrent glioblastoma (GB) when temozolomide-based radiochemotherapy fails. In theory, intra-arterial (IA) delivery of cytotoxic agents could achieve higher drug concentrations in tumors compared to intravenous injection. Moreover, choosing a highly lipid-soluble drug could make the most of the first-pass effect. Here, we evaluated idarubicin (IDA), a lipophilic anthracycline, in an in vitro assay using four human GB cell lines and compared it with 11 other drugs previously used for the IA treatment of brain tumors. Despite impressive in vitro cytotoxicity, IA IDA did not produce a beneficial effect in 2 patients with recurrent GB.
Case Rep Oncol 2016;9:499–505
http://ift.tt/2bynshF
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- Intra-Arterial Delivery of Idarubicin in Two Patie...
- Applied Sciences, Vol. 6, Pages 242: L1 Adaptive C...
- Sustainability, Vol. 8, Pages 852: Perception of C...
- Energies, Vol. 9, Pages 686: Diffusion Length Mapp...
- Sustainability, Vol. 8, Pages 849: Spatial Correla...
- Universe, Vol. 2, Pages 17: What Is the Validity D...
- Water, Vol. 8, Pages 362: Monthly Precipitation Pa...
- Sustainability, Vol. 8, Pages 846: Impacts of FDI ...
- Sustainability, Vol. 8, Pages 856: Biogenic Amines...
- Energies, Vol. 9, Pages 690: Design and Analysis o...
- Energies, Vol. 9, Pages 685: Comparison of Nitroge...
- Sensors, Vol. 16, Pages 1376: Mixed Criticality Sc...
- Sustainability, Vol. 8, Pages 855: Natural Ventila...
- Sustainability, Vol. 8, Pages 853: Valuing Ecosyst...
- Foods, Vol. 5, Pages 57: Antimicrobial Active Pack...
- Sustainability, Vol. 8, Pages 860: Thriving Organi...
- Sustainability, Vol. 8, Pages 854: Synergy and Tra...
- Electronics, Vol. 5, Pages 49: Impact of Degraded ...
- Sports, Vol. 4, Pages 45: Coffee and Caffeine Inge...
- Hemodynamics-Driven Deposition of Intraluminal Thr...
- The Effect of Esmolol on Tissue Perfusion and Clin...
- Molecular Imaging for Personalized Medicine
- Biosynthesis and Characterization of Silver Nanopa...
- Synergistic Effect of Mesoporous Silica and Hydrox...
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- The role of placental histopathological lesions in...
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Δευτέρα 29 Αυγούστου 2016
Intra-Arterial Delivery of Idarubicin in Two Patients with Glioblastoma
Applied Sciences, Vol. 6, Pages 242: L1 Adaptive Control for a Vertical Rotor Orientation System
Bottom-fixed vertical rotating devices are widely used in industrial and civilian fields. The free upside of the rotor will cause vibration and lead to noise and damage during operation. Meanwhile, parameter uncertainties, nonlinearities and external disturbances will further deteriorate the performance of the rotor. Therefore, in this paper, we present a rotor orientation control system based on an active magnetic bearing with L 1 adaptive control to restrain the influence of the nonlinearity and uncertainty and reduce the vibration amplitude of the vertical rotor. The boundedness and stability of the adaptive system are analyzed via a theoretical derivation. The impact of the adaptive gain is discussed through simulation. An experimental rig based on dSPACE is designed to test the validity of the rotor orientation system. The experimental results show that the relative vibration amplitude of the rotor using the L 1 adaptive controller will be reduced to ∼50% of that in the initial state, which is a 10% greater reduction than can be achieved with the nonadaptive controller. The control approach in this paper is of some significance to solve the orientation control problem in a low-speed vertical rotor with uncertainties and nonlinearities.
http://ift.tt/2bCiDWw
Sustainability, Vol. 8, Pages 852: Perception of Cabin Air Quality among Drivers and Passengers
Air analysis inside vehicles is a problem that can be interpreted from several perspectives. This research is oriented towards the perception of air quality within a car, regarding a situation of cars in stationary traffic. Carbon dioxide measurements were made using a Trotec Data Logger Air Quality CO2 BZ30 machine inside different standing vehicles with up to five occupants, with and without circulating air. The perception of the air quality was measured on a Likert-type scale with seven levels on a sample group of 60 students. The results highlight, on the one hand, the conditions under which the CO2 in the cabin air can reach concentrations which are, according to new data, considered to influence the cognitive capacity of occupants in the car, and on the other hand, they present a global assessment of the air quality in the vehicle when critical values of CO2 have been reached. If the air exchange rates inside a car are low, this degrades the air quality in such a way that it affects the concentration and reactions necessary for safe driving without perceiving any discomfort that would put the drivers or the passengers on alert.
http://ift.tt/2bLdDSK
Energies, Vol. 9, Pages 686: Diffusion Length Mapping for Dye-Sensitized Solar Cells
The diffusion length (L) of photogenerated carriers in the nanoporous electrode is a key parameter that summarizes the collection efficiency behavior in dye-sensitized solar cells (DSCs). At present, there are few techniques able to spatially resolve L over the active area of the device. Most of them require contact patterning and, hence, are intrinsically destructive. Here, we present the first electron diffusion length mapping system for DSCs based on steady state incident photon to collected electron (IPCE) conversion efficiency ( η I P C E ) analysis. The measurement is conducted by acquiring complete transmittance ( T DSC ) and η I P C E spectra from the photo electrode (PE) and counter electrode (CE) for each spatial point in a raster scan manner. L ( x , y ) is obtained by a least square fitting of the IPCE ratio spectrum ( I P C E R = η I P C E -CE η I P C E -PE ). An advanced feature is the ability to acquire η I P C E spectra using low-intensity probe illumination under weakly-absorbed background light (625 nm) with the device biased close to open circuit voltage. These homogeneous conditions permit the linearization of the free electron continuity equation and, hence, to obtain the collection efficiency expressions ( η COL-PE and η COL-CE ). The influence of the parameter's uncertainty has been quantified by a sensitivity study of L. The result has been validated by quantitatively comparing the average value of L map with the value estimated from electrochemical impedance spectroscopy (EIS).
http://ift.tt/2bCieUj
Sustainability, Vol. 8, Pages 849: Spatial Correlation between Type of Mountain Area and Land Use Degree in Guizhou Province, China
A scientific definition of the type of mountain area and an exploration of the spatial correlation between different types of mountain areas and regional land use at the county level are important for reasonable land resource utilization and regional sustainable development. Here, a geographic information system was used to analyze digital elevation model data and to define the extent of mountainous land and types of mountain areas in Guizhou province. Exploratory spatial data analysis was used to study the spatial coupling relation between the type of mountain area and land use degree in Guizhou province at the county level. The results were as follows: (1) Guizhou province has a high proportion of mountainous land, with a ratio of mountainous land to non-mountainous land of 88:11. The county-level administrative units in Guizhou province were exclusively mountainous, consisting of eight semi mountainous counties, nine quasi mountainous counties, 35 apparently mountainous counties, 13 type I completely mountainous counties, and 23 type II completely mountainous counties; (2) The land use degree at the county level in Guizhou province have remarkable spatial differentiation characteristics. Counties with a high cultivation coefficient are mainly located in the western area along the line between Yinjiang county and Anlong county in west Guizhou province. Counties with a large proportion of construction land or a high integrated index of land use degree are mainly distributed in the economically developed area of central Guizhou province, including parts of the counties (districts/cities) administrated by Guiyang, Zunyi, Liupanshui, Anshun, Duyun, and Kaili; (3) County-level administrative units with relatively flat topography and a low proportion of mountainous land have a large proportion of construction land and a large degree of regional land exploitation. However, the extent of cultivation of county-level administrative units under similar topography differs considerably; (4) The increase in urban land intensity and the decrease in cultivated land intensity are distinctive features of land system change in mountain areas, which is conducive to the sustainable development of mountain.
http://ift.tt/2bLem6K
Universe, Vol. 2, Pages 17: What Is the Validity Domain of Einstein’s Equations? Distributional Solutions over Singularities and Topological Links in Geometrodynamics
The existence of singularities alerts that one of the highest priorities of a centennial perspective on general relativity should be a careful re-thinking of the validity domain of Einstein's field equations. We address the problem of constructing distinguishable extensions of the smooth spacetime manifold model, which can incorporate singularities, while retaining the form of the field equations. The sheaf-theoretic formulation of this problem is tantamount to extending the algebra sheaf of smooth functions to a distribution-like algebra sheaf in which the former may be embedded, satisfying the pertinent cohomological conditions required for the coordinatization of all of the tensorial physical quantities, such that the form of the field equations is preserved. We present in detail the construction of these distribution-like algebra sheaves in terms of residue classes of sequences of smooth functions modulo the information of singular loci encoded in suitable ideals. Finally, we consider the application of these distribution-like solution sheaves in geometrodynamics by modeling topologically-circular boundaries of singular loci in three-dimensional space in terms of topological links. It turns out that the Borromean link represents higher order wormhole solutions.
http://ift.tt/2bCjNBg
Water, Vol. 8, Pages 362: Monthly Precipitation Patterns in a Region Vulnerable to Climate-Related Hazards—A Case Study from Poland
Precipitation totals at annual and monthly scale are key elements affecting water availability for a number of human activities. Thus, the multi-year variability and probability distribution of precipitation form the basis information for water management and damage risk assessment (caused by drought and heavy rains). The main goal of this paper is to analyse the precipitation patterns and to determine the non-exceedance probability (p, %) of extreme monthly precipitation in the region influenced by lignite mining and dominated by traditional agricultural production. Monthly precipitation totals recorded in 1961–2010 at four weather stations close to the analysed region were examined, including comparative analysis of precipitation patterns between the stations. Different non-exceedance probability (p, %) was determined with focus on extreme precipitation. Annual and monthly precipitation was characterised by a large variation of values. Temporal variability was larger than the spatial variability. The highest average sums were registered in July and the lowest in February. Minimum monthly precipitation (<10 mm) were recorded between January and April, and in October at all four weather stations. Maximum totals, amounting to more than 200 mm, were noted in July. The largest share of absolute minimum and maximum monthly precipitation was recorded at the turn of 20th and 21st centuries. Temporal and spatial distribution of precipitation for very dry, abnormally dry and extremely dry months (p ≤ 20%) were characterised by lower dispersion of values compared with wet months (p ≥ 80%). The precipitation probability distribution at p ≤ 20% may be useful to determine agricultural drought risk assessment in the region. Monthly precipitation at p ≥ 80% may be the background for planning drainage system efficiency and assessment of flooding risk of lignite deposits.
http://ift.tt/2cl0OPH
Sustainability, Vol. 8, Pages 846: Impacts of FDI Renewable Energy Technology Spillover on China’s Energy Industry Performance
Environmental friendly renewable energy plays an indispensable role in energy industry development. Foreign direct investment (FDI) in advanced renewable energy technology spillover is promising to improve technological capability and promote China's energy industry performance growth. In this paper, the impacts of FDI renewable energy technology spillover on China's energy industry performance are analyzed based on theoretical and empirical studies. Firstly, three hypotheses are proposed to illustrate the relationships between FDI renewable energy technology spillover and three energy industry performances including economic, environmental, and innovative performances. To verify the hypotheses, techniques including factor analysis and data envelopment analysis (DEA) are employed to quantify the FDI renewable energy technology spillover and the energy industry performance of China, respectively. Furthermore, a panel data regression model is proposed to measure the impacts of FDI renewable energy technology spillover on China's energy industry performance. Finally, energy industries of 30 different provinces in China based on the yearbook data from 2005 to 2011 are comparatively analyzed for evaluating the impacts through the empirical research. The results demonstrate that FDI renewable energy technology spillover has positive impacts on China's energy industry performance. It can also be found that the technology spillover effects are more obvious in economic and technological developed regions. Finally, four suggestions are provided to enhance energy industry performance and promote renewable energy technology spillover in China.
http://ift.tt/2bLlJWZ
Sustainability, Vol. 8, Pages 856: Biogenic Amines as Quality Marker in Organic and Fair-Trade Cocoa-Based Products
In this study, the quantitative determination of eight biogenic amines (cadaverine, serotonin, histamine, spermidine, spermine, tyramine, putrescine and β-phenylethylamine) by an liquid chromatography method with evaporative light scattering detection was performed. The analysis of several samples of conventional, organic and fair trade cocoa-derivatives showed that organic and fair trade samples always contain much lower amine concentrations in comparison with their conventional counterparts, supporting the idea that biogenic amines can be regarded as cocoa quality markers. Irrespective of the kind of sample, results also showed that the most abundant amines were histamine, tyramine, spermidine, putrescine and spermine while β-phenylethylamine, cadaverine and serotonine have been found more rarely, all the amines never reaching dangerous amounts for consumer health. With the aim to confirm the experimental results, clustering analysis was performed on samples and instrumental results using principal component analysis.
http://ift.tt/2cl0Jvq
Energies, Vol. 9, Pages 690: Design and Analysis of Nano-Structured Gratings for Conversion Efficiency Improvement in GaAs Solar Cells
This paper presents the design and analysis of nano-structured gratings to improve the conversion efficiency in GaAs solar cells by reducing the light reflection losses. A finite-difference time domain (FDTD) simulation tool is used to design and simulate the light reflection losses of the subwavelength grating (SWG) structure in GaAs solar cells. The SWG structures perform as an excellent alternative antireflective (AR) coating due to their capacity to reduce the reflection losses in GaAs solar cells. It allows the gradual change in the refractive index that confirms an excellent AR and the light trapping properties, when compared with the planar thin film structures. The nano-rod structure performs as a single layer AR coating, whereas the triangular (i.e., conical or perfect cone) and parabolic (i.e., trapezoidal/truncated cone) shaped nano-grating structures perform as a multilayer AR coating. The simulation results confirm that the reflection loss of triangular-shaped nano-grating structures having a 300-nm grating height and a 830-nm period is about 2%, which is about 28% less than the flat type substrates. It also found that the intermediate (i.e., trapezoidal and parabolic)-shaped structures, the light reflection loss is lower than the rectangular shaped nano-grating structure, but higher than the triangular shaped nano-grating structure. This analysis confirmed that the triangular shaped nano-gratings are an excellent alternative AR coating for conversion efficiency improvement in GaAs solar cells.
http://ift.tt/2bLlWJW
Energies, Vol. 9, Pages 685: Comparison of Nitrogen Depletion and Repletion on Lipid Production in Yeast and Fungal Species
Although it is well known that low nitrogen stimulates lipid accumulation, especially for algae and some oleaginous yeast, few studies have been conducted in fungal species, especially on the impact of different nitrogen deficiency strategies. In this study, we use two promising consolidated bioprocessing (CBP) candidates to examine the impact of two nitrogen deficiency strategies on lipid production, which are the extensively investigated oleaginous yeast Yarrowia lipolytica, and the commercial cellulase producer Trichoderma reesei. We first utilized bioinformatics approaches to reconstruct the fatty acid metabolic pathway and demonstrated the presence of a triacylglycerol (TAG) biosynthesis pathway in Trichoderma reesei. We then examined the lipid production of Trichoderma reesei and Y. lipomyces in different media using two nitrogen deficiency strategies of nitrogen natural repletion and nitrogen depletion through centrifugation. Our results demonstrated that nitrogen depletion was better than nitrogen repletion with about 30% lipid increase for Trichoderma reesei and Y. lipomyces, and could be an option to improve lipid production in both oleaginous yeast and filamentous fungal species. The resulting distinctive lipid composition profiles indicated that the impacts of nitrogen depletion on yeast were different from those for fungal species. Under three types of C/N ratio conditions, C16 and C18 fatty acids were the predominant forms of lipids for both Trichoderma reesei and Y. lipolytica. While the overall fatty acid methyl ester (FAME) profiles of Trichoderma reesei were similar, the overall FAME profiles of Y. lipolytica observed a shift. The fatty acid metabolic pathway reconstructed in this work supports previous reports of lipid production in T. reesei, and provides a pathway for future omics studies and metabolic engineering efforts. Further investigation to identify the genetic targets responsible for the effect of nitrogen depletion on lipid production improvement will facilitate strain engineering to boost lipid production under more optimal conditions for productivity than those required for nitrogen depletion.
http://ift.tt/2cl21GO
Sensors, Vol. 16, Pages 1376: Mixed Criticality Scheduling for Industrial Wireless Sensor Networks
Wireless sensor networks (WSNs) have been widely used in industrial systems. Their real-time performance and reliability are fundamental to industrial production. Many works have studied the two aspects, but only focus on single criticality WSNs. Mixed criticality requirements exist in many advanced applications in which different data flows have different levels of importance (or criticality). In this paper, first, we propose a scheduling algorithm, which guarantees the real-time performance and reliability requirements of data flows with different levels of criticality. The algorithm supports centralized optimization and adaptive adjustment. It is able to improve both the scheduling performance and flexibility. Then, we provide the schedulability test through rigorous theoretical analysis. We conduct extensive simulations, and the results demonstrate that the proposed scheduling algorithm and analysis significantly outperform existing ones.
http://ift.tt/2bLlUSb
Sustainability, Vol. 8, Pages 855: Natural Ventilation Building Design Approach in Mediterranean Regions—A Case Study at the Valencian Coastal Regional Scale (Spain)
Environmental awareness has led to an increased concern about low carbon technologies implementation. Among these technologies, the following research is focused on the natural ventilation effect evaluation in buildings prior to its construction. The aim is to select the most suitable architectural solution to ensure comfortable indoor environment in the most efficient way in the early building design stage. The design approach takes into account the wind conditions in the region and the building surroundings to evaluate the façade opening distribution impact on natural ventilation performance. The design approach is based on computational fluid dynamics (CFD). In this article, a case study located in the Valencian Community (Spain) is depicted. The Valencian Community coastal climatic conditions are evaluated to assess the low carbon technology energy saving potential. Moreover, the main drivers and barriers involved in the design approach implementation in the region are discussed. The conclusions show that the natural ventilation design approach can improve up to 9.7% the building energy performance respect an initial building design, in which natural ventilation has not been considered. The results contribute to an assessment of the complete low carbon technology effect in the region.
http://ift.tt/2cl1Xqy
Sustainability, Vol. 8, Pages 853: Valuing Ecosystem Services and Disservices across Heterogeneous Green Spaces
This study investigates small-scale variability in ecosystem services and disservices that is important for sustainable planning in urban areas (including suburbs surrounding the urban core). We quantified and valued natural capital (tree and soil carbon stocks) ecosystem services (annual tree carbon sequestration and pollutant uptake, and stormwater runoff reduction) and disservices (greenhouse gas emissions and soil soluble reactive phosphorus) within a 30-hectare heterogeneous green space that included approximately 13% wetland, 13% prairie, 16% forest, and 55% subdivision. We found similar soil organic carbon across green space types, but spatial heterogeneity in other ecosystem services and disservices. The value of forest tree carbon stock was estimated at approximately $10,000 per hectare. Tree carbon sequestration, and pollutant uptake added benefits of $1000+ per hectare per year. Annual per hectare benefits from tree carbon stock and ecosystem services in the subdivision were each 63% of forest values. Total annual greenhouse gas emissions had significant spatial and temporal variation. Soil soluble reactive phosphorus was significantly higher in the wetland than in forest and prairie. Our results have implications for urban planning. Adding or improving ecosystem service provision on small (private or public) urban or suburban lots may benefit from careful consideration of small-scale variability.
http://ift.tt/2bLlpI0
Foods, Vol. 5, Pages 57: Antimicrobial Active Packaging including Chitosan Films with Thymus vulgaris L. Essential Oil for Ready-to-Eat Meat
An active packaging system has been designed for the shelf life extension of ready to eat meat products. The package included an inner surface coated with a chitosan film with thyme essential oil (0%, 0.5%, 1%, and 2%) not in direct contact with the meat. Our aim was to reduce the impact of thyme essential oil (EO) on meat sensory properties by using a chemotype with low odor intensity. The pH, color parameters, microbial populations, and sensory properties were assessed during 4 weeks of refrigerated storage. The presence of EO films reduced yeast populations, whereas aerobic mesophilic bacteria, lactic acid bacteria, and enterobacteria were not affected by the presence of the EO in the films. Meat color preservation (a *) was enhanced in the presence of EO, giving a better appearance to the packaged meat. The presence of the chitosan-EO layer reduced water condensation inside the package, whereas packages containing only chitosan had evident water droplets. Thyme odor was perceived as desirable in cooked meat, and the typical product odor intensity decreased by increasing the EO concentration. Further studies should point towards developing oil blends or combinations with natural antimicrobial agents to be incorporated into the film to improve its antimicrobial properties.
http://ift.tt/2cl20mu
Sustainability, Vol. 8, Pages 860: Thriving Organizational Sustainability through Innovation: Incivility Climate and Teamwork
The present study examines the association between team incivility climate and team members' perceived support for innovation. To extend findings on the negative effects of incivility (which are low intensity deviant behaviors, such as rudeness) in studies focusing on the individual level, the effects of organizational incivility are examined at the work team level. Drawing on the spiral model of incivility and the literature on teams, this study suggests that team incivility climate has a negative impact on perceived support for innovation through team members' teamwork behaviors. Using data collected from 411 subordinates on 62 work teams, the hypothesized mediation model is tested. The results show a negative effect of team incivility climate on teamwork and a positive effect of teamwork on perceived support for innovation, supporting the hypothesized negative indirect effect. Research and practical implications for organizational sustainability are discussed.
http://ift.tt/2bLlOKi
Sustainability, Vol. 8, Pages 854: Synergy and Transition of Recovery Efficiency of Nitrogen Fertilizer in Various Rice Genotypes under Organic Farming
Despite the growing demand for organic products, research on organic farming (OF) such as genotype screening, fertilizer application and nutrition uptake remains limited. This study focused on comparisons of the apparent recovery efficiency of nitrogen fertilizer (REN) in rice grown under OF and conventional farming (CF). Thirty-two representative conventional Japonica rice varieties were field grown under five different treatments: control check (CK); organic farming with low, medium and high levels of organic fertilizer (LO, MO and HO, respectively); and CF. Comparisons of REN between OF and CF classified the 32 genotypes into four types: high REN under both OF and CF (type-A); high REN under OF and low REN under CF (type-B); low REN under OF and high REN under CF (type-C); and low REN under both OF and CF (type-D). Though the yield and REN of all the rice varieties were higher with CF than with OF, organic N efficient type-A and B were able to maintain relatively high grain yield under OF. Physiological activities in flag leaves of the four types from booting to maturity were subsequently investigated under OF and CF. Under OF, high values of soil and plant analyzer development (SPAD) and N were observed in type-B varieties, while in contrast, both indexes slowly decreased in type-C varieties under CF. Moreover, the decline in N content in type-C and D varieties was greater under OF than CF. The decrease in glutamine synthetase (GS), glutamic-pyruvic transaminase (GPT) and glutamic oxaloacetic transaminase (GOT) activity in flag leaves was smaller under OF than CF in type-A and B varieties, while in contrast, type-C and D varieties showed an opposite trend. The findings suggest that OF slows the decline in key enzymes of N metabolism in organic N-efficient type rice, thus maintaining a relatively high capacity for N uptake and utilization and increasing yield during the late growth period. Accordingly, we were able to screen for varieties of rice with synergistically high REN and high grain yield under OF.
http://ift.tt/2cl1GUG
Electronics, Vol. 5, Pages 49: Impact of Degraded Communication on Interdependent Power Systems: The Application of Grid Splitting
Communication is increasingly present for managing and controlling critical infrastructures strengthening their cyber interdependencies. In electric power systems, grid splitting is a topical communication-critical application. It amounts to separating a power system into islands in response to an impending instability, e.g., loss of generator synchronism due to a component fault, by appropriately disconnecting transmission lines and grouping synchronous generators. The successful application of grid splitting depends on the communication infrastructure to collect system-wide synchronized measurements and to relay the command to open line switches. Grid splitting may be ineffective if communication is degraded and its outcome may also depend on the system loading conditions. This paper investigates the effects of degraded communication and load variability on grid splitting. To this aim, a communication delay model is coupled with a transient electrical model and applied to the IEEE 39-Bus and the IEEE 118-Bus Test System. Case studies show that the loss of generator synchronism following a fault is mitigated by timely splitting the network into islands. On the other hand, the results show that communication delays and increased network flows can degrade the performance of grid splitting. The developed framework enables the identification of the requirements of the dedicated communication infrastructure for a successful grid-splitting procedure.
http://ift.tt/2bLm7VM
Sports, Vol. 4, Pages 45: Coffee and Caffeine Ingestion Have Little Effect on Repeated Sprint Cycling in Relatively Untrained Males
The present study investigated the effect of ingesting caffeine-dose-matched anhydrous caffeine or coffee on the performance of repeated sprints. Twelve recreationally active males (mean ± SD age: 22 ± 2 years, height: 1.78 ± 0.07 m, body mass: 81 ± 16 kg) completed eighteen 4 s sprints with 116 s recovery on a cycle ergometer on four separate occasions in a double-blind, randomised, counterbalanced crossover design. Participants ingested either 3 mg·kg−1 of caffeine (CAF), 0.09 g·kg−1 coffee, which provided 3 mg·kg−1 of caffeine (COF), a taste-matched placebo beverage (PLA), or a control condition (CON) 45 min prior to commencing the exercise protocol. Peak and mean power output and rating of perceived exertion (RPE) were recorded for each sprint. There were no significant differences in peak power output (CAF: 949 ± 199 W, COF: 949 ± 174 W, PLA: 971 ± 149 W and CON: 975 ± 170 W; p = 0.872; η P 2 = 0.02) or mean power output (CAF: 873 ± 172 W, COF: 862 ± 44 W, PLA: 887 ± 119 W and CON: 892 ± 143 W; p = 0.819; η P 2 = 0.03) between experimental conditions. Mean RPE was similar for all trials (CAF: 11 ± 2, COF: 11 ± 2, PLA: 11 ± 2 and CON: 11 ± 2; p = 0.927; η P 2 = 0.01). Neither the ingestion of COF or CAF improved repeated sprint cycling performance in relatively untrained males.
http://ift.tt/2cl1QeJ
Hemodynamics-Driven Deposition of Intraluminal Thrombus in Abdominal Aortic Aneurysms
Summary
Accumulating evidence suggests that intraluminal thrombus plays many roles in the natural history of abdominal aortic aneurysms. There is, therefore, a pressing need for computational models that can describe and predict the initiation and progression of thrombus in aneurysms. In this paper, we introduce a phenomenological metric for thrombus deposition potential and use hemodynamic simulations based on medical images from six patients to identify best-fit values of the two key model parameters. We then introduce a shape optimization method to predict the associated radial growth of the thrombus into the lumen based on the expectation that thrombus initiation will create a thrombogenic surface, which in turn will promote growth until increasing hemodynamically induced frictional forces prevent any further cell or protein deposition. Comparisons between predicted and actual intraluminal thrombus in the six patient-specific aneurysms suggest that this phenomenological description provides a good first estimate of thrombus deposition. We submit further that, because the biologically active region of the thrombus appears to be confined to a thin luminal layer, predictions of morphology alone may be sufficient to inform fluid-solid-growth models of aneurysmal growth and remodeling.
http://ift.tt/2c84fbc
The Effect of Esmolol on Tissue Perfusion and Clinical Prognosis of Patients with Severe Sepsis: A Prospective Cohort Study
Purpose. This study was aimed at investigating the effect of esmolol on tissue perfusion and the clinical prognosis of patients with severe sepsis. Materials and Methods. One hundred fifty-one patients with severe sepsis were selected and divided into the esmolol group () or the control group (), who received conventional antiseptic shock treatment. The esmolol group received a continuous infusion of esmolol via a central venous catheter, and their heart rate (HR) was maintained at 70–100 bpm over 72 hours. Results. The HR of all patients reached the target level within 72 hours of treatment for both groups. The effect of esmolol on PvaCO2 was only significant at 48 hours (). ScvO2 increased in the esmolol group and decreased in the control group (). Lac showed a linear downward trend over the treatment time, but the reduction was more significant in the control group at 48 hours () between the two groups. Kaplan-Meier analysis showed a significantly shorter duration of mechanical ventilation in the esmolol group than in the control group (). Conclusions. Esmolol reduced the duration of mechanical ventilation in patients with severe sepsis, with no significant effect on circulatory function or tissue perfusion.
http://ift.tt/2c256qY
Biosynthesis and Characterization of Silver Nanoparticles by Aspergillus Species
Currently, researchers turn to natural processes such as using biological microorganisms in order to develop reliable and ecofriendly methods for the synthesis of metallic nanoparticles. In this study, we have investigated extracellular biosynthesis of silver nanoparticles using four Aspergillus species including A. fumigatus, A. clavatus, A. niger, and A. flavus. We have also analyzed nitrate reductase activity in the studied species in order to determine the probable role of this enzyme in the biosynthesis of silver nanoparticles. The formation of silver nanoparticles in the cell filtrates was confirmed by the passage of laser light, change in the color of cell filtrates, absorption peak at 430 nm in UV-Vis spectra, and atomic force microscopy (AFM). There was a logical relationship between the efficiencies of studied Aspergillus species in the production of silver nanoparticles and their nitrate reductase activity. A. fumigatus as the most efficient species showed the highest nitrate reductase activity among the studied species while A. flavus exhibited the lowest capacity in the biosynthesis of silver nanoparticles which was in accord with its low nitrate reductase activity. The present study showed that Aspergillus species had potential for the biosynthesis of silver nanoparticles depending on their nitrate reductase activity.
http://ift.tt/2c23Fch
Synergistic Effect of Mesoporous Silica and Hydroxyapatite in Loaded Poly(DL-lactic-co-glycolic acid) Microspheres on the Regeneration of Bone Defects
A microsphere composite made of poly(DL-lactic-co-glycolic acid) (PLGA), mesoporous silica nanoparticle (MSN), and nanohydroxyapatite (nHA) (PLGA-MSN/nHA) was prepared and evaluated as bone tissue engineering materials. The objective of this study was to investigate the synergistic effect of MSN/nHA on biocompatibility as well as its potential ability for bone formation. First, we found that this PLGA-MSN/nHA composite performed good characteristics on microstructure, mechanical strength, and wettability. By cell culture experiments, the adhesion and proliferation rate of the cells seeded on PLGA-MSN/nHA composite was higher than those of the controls and high levels of osteogenetic factors such as ALP and Runx-2 were detected by reverse transcriptase polymerase chain reaction. Finally, this PLGA-MSN/nHA composite was implanted into the femur bone defect in a rabbit model, and its ability to induce bone regeneration was observed by histological examinations. Twelve weeks after implantation, the bone defects had significantly more formation of mature bone and less residual materials than in the controls. These results demonstrate that this PLGA-MSN/nHA composite, introducing both MSN and nHA into PLGA microspheres, can improve the biocompatibility and osteoinductivity of composite in vitro and in vivo and had potential application in bone regeneration.
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The role of placental histopathological lesions in predicting recurrence of preeclampsia
Abstract
Objective
We aimed to study the role of placental pathology in the prediction of preeclampsia (PE) recurrence.
Methods
The medical records and pathological placental reports of all women diagnosed with PE, during 2008-2015, were reviewed. The study population was divided according to the outcome of their subsequent pregnancy: those who did (recurrence group) or did not (no-recurrence group), develop recurrent PE. Data regarding maternal characteristics and placental maternal/fetal vascular malperfusion lesions, of the initial pregnancies, were compared. Two prediction models were generated for PE recurrence.
Results
Compared to the no-recurrence group (n = 130), the recurrence group (n = 96) was characterized by lower gestational age (p < 0.001), longer inter-pregnancy interval (p = 0.012), and higher rate of severe features (p < 0.001). By logistic regression analysis composite maternal (aOR = 3.05, 95%CI 1.39-6.71,p = 0.005), fetal (aOR = 9.31, 95%CI 3.9-22.1,p < 0.001), and concurrent maternal + fetal (aOR = 13.94, 95%CI 5.08-38.21,p < 0.001) vascular malperfusion lesions, were found to be independently associated with recurrence. A clinical prediction model accounted for 20.8% of PE recurrence (R2 = 0.208, AUC = 0.732), while a clinical-pathological model accounted for 34.2% of recurrence (R2 = 0.342, AUC = 0.80).
Conclusion
Placental maternal and fetal vascular malperfusion lesions are independently associated with increased risk for PE recurrence. A clinical-pathological prediction model for recurrence of preeclampsia is superior to a prediction model based merely on clinical factors. This article is protected by copyright. All rights reserved.
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Agronomy, Vol. 6, Pages 41: Special Issue: Nitrogen Transport and Assimilation in Plants
The doubling of the world's agricultural production for the past four decades has been associated with a seven-fold increase in nitrogen (N) fertilization [1] which has caused major detrimental impacts onthediversityandfunctioningofthenon-agriculturalbacterial,animalandplantecosystems,notably through the process of freshwater and marine ecosystem eutrophication [2].[...]
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Αλέξανδρος Γ. Σφακιανάκης Medicine by Alexandros G. Sfakianakis,Anapafseos 5 Agios Nikolaos 72100 Crete Greece,00302841026182,0030693260717...
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heory of COVID-19 pathogenesis Publication date: November 2020Source: Medical Hypotheses, Volume 144Author(s): Yuichiro J. Suzuki ScienceD...
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