1,370 research outputs found
Hypoxia Preconditioning Increases Survival and Decreases Expression of Toll-like Receptor 4 in Pulmonary Artery Endothelial Cells Exposed to Lipopolysaccharide
Pulmonary or systemic infections and hypoxemic respiratory failure are among the leading causes of admission to intensive care units, and these conditions frequently exist in sequence or in tandem. Inflammatory responses to infections are reproduced by lipopolysaccharide (LPS) engaging Toll-like receptor 4 (TLR4). Apoptosis is a hallmark of lung injury in sepsis. This study was conducted to determine whether preexposure to LPS or hypoxia modulated the survival of pulmonary artery endothelial cells (PAECs). We also investigated the role TLR4 receptor expression plays in apoptosis due to these conditions. Bovine PAECs were cultured in hypoxic or normoxic environments and treated with LPS. TLR4 antagonist TAK-242 was used to probe the role played by TLR4 receptors in cell survival. Cell apoptosis and survival were measured by caspase 3 activity and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) incorporation. TLR4 expression and tumor necrosis factor α (TNF-α) production were also determined. LPS increased caspase 3 activity in a TAK-242-sensitive manner and decreased MTT incorporation. Apoptosis was decreased in PAECs preconditioned with hypoxia prior to LPS exposure. LPS increased TNF-α production, and hypoxic preconditioning blunted it. Hypoxic preconditioning reduced LPS-induced TLR4 messenger RNA and TLR4 protein. TAK-242 decreased to baseline the LPS-stimulated expression of TLR4 messenger RNA regardless of environmental conditions. In contrast, LPS followed by hypoxia substantially increased apoptosis and cell death. In conclusion, protection from LPS-stimulated PAEC apoptosis by hypoxic preconditioning is attributable in part to reduction in TLR4 expression. If these signaling pathways apply to septic patients, they may account for differing sensitivities of individuals to acute lung injury depending on oxygen tensions in PAECs in vivo
Accuracies of Soil Moisture Estimations Using a Semi-Empirical Model over Bare Soil Agricultural Croplands from Sentinel-1 SAR Data
This study describes a semi-empirical model developed to estimate volumetric soil
moisture ( v
ϑ) in bare soils during the dry season (March–May) using C-band (5.42 GHz) synthetic
aperture radar (SAR) imagery acquired from the Sentinel-1 European satellite platform at a 20 m
spatial resolution. The semi-empirical model was developed using backscatter coefficient (σ° dB)
and in situ soil moisture collected from Siruguppa taluk (sub-district) in the Karnataka state of
India. The backscatter coefficients 0
VV σ and 0
VH σ were extracted from SAR images at 62
geo-referenced locations where ground sampling and volumetric soil moisture were measured at a
10 cm (0–10 cm) depth using a soil core sampler and a standard gravimetric method during the dry
months (March–May) of 2017 and 2018. A linear equation was proposed by combining 0
VV σ and
0
VH σ to estimate soil moisture. Both localized and generalized linear models were derived.
Thirty-nine localized linear models were obtained using the 13 Sentinel-1 images used in this
study, considering each polarimetric channel Co-Polarization (VV) and Cross-Polarization(VH)
separately, and also their linear combination of VV + VH. Furthermore, nine generalized linear
models were derived using all the Sentinel-1 images acquired in 2017 and 2018; three generalized
models were derived by combining the two years (2017 and 2018) for each polarimetric channel;
and three more models were derived for the linear combination of 0
VV σ and 0
VH σ . The above set of
equations were validated and the Root Mean Square Error (RMSE) was 0.030 and 0.030 for 2017 and
2018, respectively, and 0.02 for the combined years of 2017 and 2018. Both localized and
generalized models were compared with in situ data. Both kind of models revealed that the linear
combination of 0
VV σ + 0
VH σ showed a significantly higher R2 than the individual polarimetric
channels
An aggregator-based-strategy to minimize the cost of energy consumption by optimal utilization of energy resources in an apartment building
© 2019 IEEE. Buildings and transport consume two thirds of the total global energy. It is desirable to maximize the use of renewable generation in these sectors, and to optimize the use of that energy by managing diverse sources and loads. This is particularly challenging in high-density residential premises where the space for such infrastructure is limited, and storage can have significant impact on energy utilization and demand. In this paper, we have proposed an aggregator-based-strategy (ABS) to optimally utilize the available energy resources and storage in an apartment building with twenty households, each having an electric vehicle (EV), and an aggregated solar photovoltaic (PV) energy and stationary battery storage (BS) system. The strategy is flexible and can be applied to any building with EVs, solar PV and BS to minimize the cost of energy consumption without compromising the flexibility of energy usage or travel requirements. The model also accounts for the battery capacity degradation and its associated cost to make it more realistic. The model is evaluated using real data and the results show that the strategy not only reduces the cost of energy consumption but also reduces the amount of energy drawn from the grid significantly
Target Population Environments and Pest Distribution Modelling: An Approach towards Pest Prioritization and Preparedness
The transboundary crop pest and disease (P&D) outbreaks over large geographical regions jeopardizes the food security and have broad economic, social and environmental impacts. The upsurge of new crop P&D, such as fall armyworm; cassava mosaic and brown streak virus; banana fusarium wilt tropical race 4 and wheat stem rust Ug99 are having serious repercussions on agriculture. Climate change is, in part, responsible for food chain catastrophes arising from these transboundary P&D. However, there is clear evidence that climate change impacts are altering the distribution of crop P&D. Such accelerated events require more attention on a greater scale to strengthen food security and protect the livelihoods of poor and most vulnerable countries of the world. A well-defined P&D ranking and distribution will focus on supporting policy-making, integrated P&D management as well as tangible pre-emptive breeding strategies at large scale. Here, we have used chickpea homogenous systems units (HSUs) defined by mechanistic models and geo-bio-physical parameters; over which the P&D distribution and rankings were over-layered. The chickpea P&D severity, distributions, social impact and key drivers responsible for spread on these locations were identified by using meta-analysis. Further, in order to understand the possible risks and consequences of P&D population growth and geographical expansion, the CLIMEX package was used. We aim to compare the pest distribution generic models and prioritization methodologies for emerging regional specific P&D. These findings would support policy intrusions associated with long term transformative adaptation strategies for climate change
Effect of garlic supplementation on zootechnical performance and hepato-renal functions in nitrate-treated rabbits
The effect of garlic supplementation on zootechnical performance and hepato-renal functions of rabbits exposed to experimental nitrate poisoning was evaluated. Adult male 6-8 week-old albino rabbits (n= 24) were randomly divided into four groups (A - D) and subjected to nitrate intoxication through the oral administration of sodium nitrate solution at 2 ml/kg bodyweight per day for 40 days. Group A was a control that received no treatment except sodium nitrate. Rabbits in groups B and C were treated with 1% methylene blue solution (2 mg/kg bodyweight per day) and aqueous garlic extract (500 mg/kg bodyweight per day) through intraperitoneal and oral routes, respectively. Rabbits in group D were treated with both 1% methylene blue solution (2 mg/kg bodyweight per day, intraperitoneally) and aqueous garlic extract (500 mg/kg bodyweight per day, orally). On completion of the treatment period, the groups were compared in growth performance, biochemical profile and histopathological changes of hepato-renal tissues. Although the total feed consumption of the groups remained comparable, Group C showed relatively better weight gain and feed conversion ratio (FCR). Likewise, garlic extract significantly increased the serum bilirubin concentration and reduced the level of other biochemical attributes in comparison with control animals. The hepatic and renal tissues of Groups C and D remained normal, whereas those of the control group exhibited distinct histopathological alterations. It was concluded that garlic supplementation ameliorated the deleterious effects of nitrate intoxication on production performance and hepato-renal functions of rabbits
Convertible staircase lift
The present work investigates the design and analysis of a staircase lift, which can be used as a Material Handling System. A staircase lift is a mechanical device for lifting people and wheelchairs up and down the stairs, who may find difficulty in doing so themselves. For sufficiently wide stairs, a rail is mounted to the treads of the stairs. A chair or lifting platform is attached to the rail. A person on the chair or platform is lifted as the chair or platform moves along the rail, old age and goods are to be carried across the staircase. A staircase lift is a type of lift that can be mounted on the staircase without altering civil structure. Not only altering, but the person need not change the seat from the wheelchair to the staircase lift, there is a foldable supporting rod for the staircase lift which directly attaches to the wheelchair. This lift runs on electric power and consists of a motor, reduction gearbox, rope drive, two rails and a sliding chair. In this system, we use a DC motor for changing the polarity of the power supply which will make the motor run in reverse direction. Advantages over the conventional hydraulic lift are no civil structure and alteration is required, low cost, less bulkiness, less power, less maintenance required. Easy design, easy installations can be of industrial use too. Moreover, considering some drawbacks due to weight carrying capacity completely depends upon the capacity of the motor. There is a lot of scope for further modification in the project as using a monorail instead of two, using a belt drive or chain drive instead of a rope drive. Incorporation and automation/timer unit will ease the use of the device. Rack and carrier arrangement for using the device for a curved staircase and use of work & roller reduction gear assembly
Shape Analysis of Traffic Flow Curves using a Hybrid Computational Analysis
This paper highlights and validates the use of shape analysis using Mathematical Morphology tools as a means to develop meaningful clustering of historical data. Furthermore, through clustering more appropriate grouping can be accomplished that can result in the better parameterization or estimation of models. This results in more effective prediction model development. Hence, in an effort to highlight this within the research herein, a Back-Propagation Neural Network is used to validate the classification achieved through the employment of MM tools. Specifically, the Granulometric Size Distribution (GSD) is used to achieve clustering of daily traffic flow patterns based solely on their shape. To ascertain the significance of shape in traffic analysis, a comparative classification analysis of original data and GSD transformed data is carried out. The results demonstrate the significance of functional shape in traffic analysis. In addition, the results validate the need for clustering prior to prediction. It is determined that a span of two through four years of traffic data is found sufficient for training to produce satisfactory BPNN performance
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