60 research outputs found
Feasibility, Architecture and Cost Considerations of Using TVWS for Rural Internet Access in 5G
The cellular technology is mostly an urban technology that has been unable to serve rural areas well. This is because the traditional cellular models are not economical for areas with low user density and lesser revenues. In 5G cellular networks, the coverage dilemma is likely to remain the same, thus widening the rural-urban digital divide further. It is about time to identify the root cause that has hindered the rural technology growth and analyse the possible options in 5G architecture to address this issue. We advocate that it can only be accomplished in two phases by sequentially addressing economic viability followed by performance progression. We deliberate how various works in literature focus on the later stage of this ‘two-phase’ problem and are not feasible to implement in the first place. We propose the concept of TV band white space (TVWS) dovetailed with 5G infrastructure for rural coverage and show that it can yield cost-effectiveness from a service provider’s perspective
A Weighted Linear Combining Scheme for Cooperative Spectrum Sensing
AbstractCooperative spectrum sensing exploits spatial diversity of secondary-users (SUs), to reliably detect the availability of a spectrum. Soft energy combining schemes have optimal detection performance at the cost of high cooperation overhead, since actual sensed data is required at the fusion center. To reduce cooperation overhead, in hard combining only local decisions are shared; however the detection performance is suboptimal due to the loss of information. In this paper, a weighted linear combining scheme is proposed in which a SU performs a local sensing test based on two threshold levels. If local test result lies between the two thresholds then the SU report neither its local decision nor sequentially estimated unknown SNR parameter values, to the fusion center. Thereby, uncertain decisions about the presence/absence of the primary-user signal are suppressed. Simulation results suggest that the detection performance of the proposed scheme is close to optimal soft combining schemes yet its overhead is similar to hard combining techniques
Biochar affects growth and biochemical activities of fenugreek (Trigonella corniculata) in cadmium polluted soil
Cadmium (Cd) has no defined biological role and may enter the food chain from polluted soils. Biochar has been proposed as an organic amendment to minimize the toxic effects of Cd for plants grown on contaminated soils. In this study, biometric and biochemical attributes of fenugreek (Trigonella corniculata) grown on artificially cadmium (Cd) contaminated soil (0, 25, 50, 75 and 100 mg Cd/kg soil) at three levels of cotton-sticks derived biochar (CSB; 0, 3 and 5 %) were studied. Data show significant decline in the growth, photosynthetic pigments (chlorophyll a, b and total, carotenoids, anthocyanin and lycopene), and physiological attributes (sub-stomatal CO2 concentrations, photosynthetic and transpiration rate) in the presence of high Cd concentrations (50 and 100 mg Cd/kg soil). However, the decline was reduced in the presence of CSB. A steady amplification in lipid peroxidation (assessed via Malondialdihyde (MDA)) and ascorbic-acid assembly was noted with increasing Cd. The concentration of Cd in the root and shoot also decreased with increasing CSB application rates from 3 % - 5 %.Overall, the greater production of protein, amino acids and sugar contents in response to higher application rates of CSB seems to be due to alleviation in Cd toxicity. Thus, cotton-sticks can be safely utilized in the form of biochar as amendment with additional benefit of reducing Cd bioavailability and toxicity to crop plants
Development of a cost-effective CVD prediction model using lifestyle factors. A cohort study in Pakistan
Background: Cardiovascular diseases (CVD) such as hypertension and
ischemic heart diseases cause 35 to 40% of deaths every year in
Pakistan. Several lifestyle factors such as dietary habits, lack of
exercise, mental stress, body habitus (i.e., body mass index, waist),
personal habits (smoking, sleep, fitness) and clinical conditions
(i.e., diabetes, dyslipidemia and hypertension) have been shown to be
strongly associated with the etiology of CVD. Epidemiological studies
in Pakistan have shown poor adherence of people to healthy lifestyle
and lack of knowledge in adopting healthy alternatives. There are well
validated cardiovascular risk estimation tools (QRISK model) that cn
predict the probability of future cardiac events. The existing tools
are based on laboratory investigations of biochemical test but there is
no widely accepted tool available that predicts the CVD risk
probability based on lifestyle factors. Aims: Aim of the current study
was to develop alternative CVD risk estimation model based on lifestyle
factors and physical attributes (without using laboratory
investigation) using QRISK model as the gold standard. Study Design:
Clinical and lifestyle data of one hundred and sixty subjects were
collected to formulate a regression model for predicting CVD risk
probability. Methods: Lifestyle factors as independent variables (IV)
include BMI, waist circumference, physical activities (stamina,
strength, flexibility, posture), smoking, general illnesses, dietary
intake, stress and physical characteristics. CVD risk probability of
QRISK Intervention computed through clinical variables was used as a
dependent variable (DV) in present research. Chronological age was also
included in analysis in addition to selected lifestyle factors.
Regression analysis, principal component analysis and bivariate
correlations were applied to assess the relationship among predictor
variables and cardiovascular risk score. Results: Chronological age,
waist circumference, BMI and strength showed significant effect on CVD
risk probability. The proposed model can be used to calculate CVD risk
probability with 72.9% accuracy for the targeted population.
Conclusion: The model involves only those features which can be
measured without any clinical test. The proposed model is rapid and
less costly hence appropriate for use in developing countries like
Pakistan
Effects of safety pattern, cabin ergonomics, and sleep on work-related stress and burnout of city and transit bus drivers in Lahore, Pakistan
The health and working environment of bus drivers is compromised in low-middle-income countries like Pakistan which leads to burnout and excessive Road Traffic Crashes. Hence, this study delves into factors affecting their safe operations from health and work environment perspectives and measures their associated stress and Burnout level. In a study of four hundred and ninety-nine (499), 86% city and 14% transit bus drivers are surveyed through a questionnaire. Stress is estimated for city and transit bus drivers, using the Effort/Reward Imbalance Model (ERI) of Siegrist, and burnout is calculated using the Copenhagen Burnout Inventory (CBI). For the determination of important determinants, descriptive and regression analyses are conducted. Findings show that stress has emerged as a negative factor for the physical and psychological health of city and transit bus drivers. Results based on bus drivers’ responses suggest that organisational awareness and emphasis on health and safety levels can significantly reduce driver stress and burnout
Procoagulant Extracellular Vesicles Alter Trophoblast Differentiation in Mice by a Thrombo-Inflammatory Mechanism
Procoagulant extracellular vesicles (EV) and platelet activation have been associated with gestational vascular complications. EV-induced platelet-mediated placental inflammasome activation has been shown to cause preeclampsia-like symptoms in mice. However, the effect of EV-mediated placental thrombo-inflammation on trophoblast differentiation remains unknown. Here, we identify that the EV-induced thrombo-inflammatory pathway modulates trophoblast morphology and differentiation. EVs and platelets reduce syncytiotrophoblast differentiation while increasing giant trophoblast and spongiotrophoblast including the glycogen-rich cells. These effects are platelet-dependent and mediated by the NLRP3 inflammasome. In humans, inflammasome activation was negatively correlated with trophoblast differentiation marker GCM1 and positively correlated with blood pressure. These data identify a crucial role of EV-induced placental thrombo-inflammation on altering trophoblast differentiation and suggest platelet activation or inflammasome activation as a therapeutic target in order to achieve successful placentation
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