431 research outputs found
Comparative study of the noise generated by the moto-compressor and that generated by the turbo-compressor
The fundamental aim of this study is to compare between the noise generated by the moto-compressor and the noise generated by the turbo-compressor operating 24H/24H on the continuous function mode; these two machines make part of the equipment of the GP1Z, a factory of hydrocarbon treatment. To attain the principal objective of this study we divided our work into two parts, in the first part we followed and evaluated the average level of the noise emitted by the two machines, whereas in the second part we studied the noise propagation emitted by the two machines and its impact on the generation of the noise. The results obtained from this study demonstrate that the noise generated by the turbo-compressor is higher than the noise generated by the moto-compressor.Keywords: noise; moto-compressor; turbo-compressor; noise maping
Quantum rotation gates with controlled nonadiabatic evolutions
Quantum gates can be implemented adiabatically and nonadiabatically. Many schemes used at
least two sequentially implemented gates to obtain an arbitrary one-qubit gate. Recently, it has
been shown that nonadiabatic gates can be realized by single-shot implementation. It has also
been shown that quantum gates can be implemented with controlled adiabatic evolutions. In this
paper, we combine the advantage of single-shot implementation with controlled adiabatic
evolutions to obtain controlled nonadiabatic evolutions. We also investigate the robustness to
different types of errors. We find that the fidelity is close to unity for realistic decoherence rate
Comparative Study on the Chronic Vascular Responses Induced by Regular Versus Occasional Waterpipe Smoke Inhalation in Mice
BACKGROUND/AIMS: Waterpipe smoke (WPS) is the second most prevalent form of smoking in the world. There are ample evidences about the vascular alterations caused by regular WPS (Reg-WPS). Nonetheless, comparison of the chronic vascular response induced by regular versus occasional WPS (Occ-WPS) exposure is very scarce. METHODS: We investigated, in BALB/c mice, the effects of Occ-WPS (30 minutes/day, 1 day/week) versus Reg-WPS (30 minutes/day, 5 days/week) for 6 months on thrombogenicity and platelet aggregation in vivo and in vitro. Moreover, various markers of endothelial integrity, inflammation and oxidative stress were assessed by enzyme-linked immunosorbent assay and colorimetric assay. Control mice were exposed to air. RESULTS: Our results showed that either Occ-WPS or Reg-WPS exposure shortened the thrombotic time in pial microvessels in vivo. Moreover, in pial venules, this effect was more marked in Reg-WPS group (-47%) compared with Occ-WPS (-34%). Similarly, exposure to either Occ-WPS or Reg-WPS reduced the prothrombin time and activated partial thromboplastin time. Platelet count was increased only in Reg-WPS exposure. Exposure to either Occ-WPS or Reg-WPS induced platelet aggregation in vitro. In addition, there was a statistically significant difference between Occ-WPS and Reg-WPS groups in platelet count and aggregation. Plasma concentration of tissue factor (+98%), P-selectin (+14%) and E-selectin (+16%) were significantly increased in Occ-WPS group compared with air exposed group. Likewise, compared with air group Reg-WPS caused an increase in concentration of tissue factor (+193%), P-selectin (+21%) and E-selectin (+42%). Nevertheless, only Reg-WPS induced a decrease (-38%) in the plasma concentration of tissue plasminogen activator. Notably, our results showed a statistically significant difference between Occ-WPS and Reg-WPS groups in the concentration of tissue factor. Erythrocyte numbers, hemoglobin concentration, hematocrit and lactate dehydrogenase activity were augmented only in Reg-WPS group compared with either control or Occ-WPS groups. Likewise, only Reg-WPS induced an increase in proinflammatory cytokines, tumor necrosis factor-α and interleukin-1β compared with either control or Occ-WPS groups. However, markers of oxidative stress including 8-isoprostane and total antioxidants were enhanced in both Occ-WPS and Reg-WPS compared with control group. CONCLUSION: Our data confirm the vascular toxicity of the chronic Reg-WPS exposure and shows that even occasional chronic exposure to WPS caused thrombosis, platelet aggregation, endothelial alterations and oxidative stress. The latter findings are an additional cause of concern about the long-term toxicity of occasional waterpipe smoking
Knowledge and preference towards mode of delivery among pregnant women in the United Arab Emirates:The Mutaba’ah study
Background: The rate of cesarean section (CS) is growing in the United Arab Emirates (UAE). Pregnant women’s knowledge on the mode of delivery, factors associated with lack of adequate knowledge, and preference towards CS delivery were investigated. Methods: Baseline cross-sectional data from 1617 pregnant women who participated in the Mutaba’ah Study between September 2018 and March 2020 were analyzed. A self-administered questionnaire inquiring about demographic and maternal characteristics, ten knowledge-based statements about mode of delivery, and one question about preference towards mode of delivery was used. Knowledge on the mode of delivery was categorized into “adequate (total score 6–10)” or “lack of adequate (total score 0–5)” knowledge. Crude and multivariable models were used to identify factors associated with “lack of adequate” knowledge on the mode of delivery and factors associated with CS preference. Results: A total of 1303 (80.6%) pregnant women (mean age 30.6 ± 5.8 years) completed the questionnaire. The majority (57.1%) were ≥30 years old, in their third trimester (54.5%), and had at least one child (76.6%). In total, 20.8% underwent CS delivery in the previous pregnancy, and 9.4% preferred CS delivery for the current pregnancy. A total of 78.4% of pregnant women lacked adequate knowledge on the mode of delivery. The level of those who lacked adequate knowledge was similar across women in different pregnancy trimesters. Young women (18–24 years) (adjusted odds ratios (aOR), 3.07, 95% confidence interval (CI), 1.07–8.86) and women who had CS delivery in the previous pregnancy (aOR, 1.90, 95% CI, 1.06–3.40) were more likely to be classified with a lack of adequate knowledge. Age (aOR, 1.08, 95% CI, 1.02–1.14), employment (aOR, 1.96, 95% CI, 1.13–3.40), or previous CS delivery (aOR, 31.10, 95% CI, 17.71–55.73) were associated with a preference towards CS delivery. Conclusion: This study showed that pregnant women may not fully appreciate the health risks associated with different modes of delivery. Therefore, antenatal care appointments should include a balanced discussion on the potential benefits and harms associated with different delivery modes.</p
Trade Privacy for Utility: A Learning-Based Privacy Pricing Game in Federated Learning
To prevent implicit privacy disclosure in sharing gradients among data owners
(DOs) under federated learning (FL), differential privacy (DP) and its variants
have become a common practice to offer formal privacy guarantees with low
overheads. However, individual DOs generally tend to inject larger DP noises
for stronger privacy provisions (which entails severe degradation of model
utility), while the curator (i.e., aggregation server) aims to minimize the
overall effect of added random noises for satisfactory model performance. To
address this conflicting goal, we propose a novel dynamic privacy pricing
(DyPP) game which allows DOs to sell individual privacy (by lowering the scale
of locally added DP noise) for differentiated economic compensations (offered
by the curator), thereby enhancing FL model utility. Considering
multi-dimensional information asymmetry among players (e.g., DO's data
distribution and privacy preference, and curator's maximum affordable payment)
as well as their varying private information in distinct FL tasks, it is hard
to directly attain the Nash equilibrium of the mixed-strategy DyPP game.
Alternatively, we devise a fast reinforcement learning algorithm with two
layers to quickly learn the optimal mixed noise-saving strategy of DOs and the
optimal mixed pricing strategy of the curator without prior knowledge of
players' private information. Experiments on real datasets validate the
feasibility and effectiveness of the proposed scheme in terms of faster
convergence speed and enhanced FL model utility with lower payment costs.Comment: Accepted by IEEE ICC202
Cardiac Inflammation, Oxidative Stress, Nrf2 Expression, and Coagulation Events in Mice with Experimental Chronic Kidney Disease
Chronic kidney disease (CKD) is known to be associated with cardiovascular dysfunction. Dietary adenine intake in mice is also known to induce CKD. However, in this experimental model, the mechanisms underlying the cardiotoxicity and coagulation disturbances are not fully understood. Here, we evaluated cardiac inflammation, oxidative stress, DNA damage, and coagulation events in mice with adenine (0.2% w/w in feed for 4 weeks)-induced CKD. Control mice were fed with normal chow for the same duration. Adenine increased water intake, urine output, relative kidney weight, the plasma concentrations of urea and creatinine, and the urinary concentrations of kidney injury molecule-1 and neutrophil gelatinase-associated lipocalin. It also decreased the body weight and creatinine clearance, and caused kidney DNA damage. Renal histological analysis showed tubular dilation and damage and neutrophilic influx. Adenine induced a significant increase in systolic blood pressure and the concentrations of troponin I, tumor necrosis factor-α, and interleukin-1β in heart homogenates. It also augmented the levels of markers of lipid peroxidation measured by malondialdehyde production and 8-isoprostane, as well as the antioxidants superoxide dismutase and catalase. Immunohistochemical analysis of the hearts showed that adenine increased the expression of nuclear factor erythroid-derived 2-like 2 by cardiomyocytes. It also caused cardiac DNA damage. Moreover, compared with the control group, adenine induced a significant increase in the number of circulating platelet and shortened the thrombotic occlusion time in pial arterioles and venules in vivo, and induced a significant reduction in the prothrombin time and activated partial thromboplastin time. In conclusion, the administration of adenine in mice induced CKD-associated cardiac inflammation, oxidative stress, Nrf2 expression, and DNA damage. It also induced prothrombotic events in vivo. Therefore, this model can be satisfactorily used to study the cardiac pathophysiological events in subjects with CKD and the effect of drug treatment thereon
Brane inflation and the fine-tuning problem
Brane inflation can provide a promissing framework for solving the
fine-tuning problem in standard inflationary models. The aim of this paper is
to illustrate the mechanism by which this can be achieved. By considering the
supersymmetric two-stage inflation model it is shown that the initial
fine-tuning of the coupling parameter can be considerably relaxed. SubPlanckian
values of the inflaton during inflation can also be obtained.Comment: 04 pages (Revtex
Impact of recurrent miscarriage on maternal outcomes in subsequent pregnancy:The Mutaba’ah study
Purpose: To estimate the prevalence of recurrent miscarriage (RM) and investigate the association between RM and adverse maternal outcomes in subsequent pregnancies. Participants and Methods: This is an interim analysis of a prospective study of 1737 pregnant women with gravidity of two or more prior to the current pregnancy. These women joined the Mutaba’ah Study between May 2017 and April 2019 and were followed up until they delivered. Hospital medical records were used to extract data on past pregnancy history and the progress and outcomes of the current pregnancy, such as gestational diabetes, preeclampsia, mode of delivery, preterm delivery, and complications at birth. Results: Amongst pregnant women with at least two previous pregnancies (n=1737), there were 234 (13.5%) women with a history of two or more consecutive miscarriages. Women with RM were slightly older, more parous, and more likely to have had previous infertility treatment (all p-values <0.05). Women with a history of RM had independently significant increased odds of cesarean section (adjusted odds ratio (aOR) 1.81, 95% CI 1.24–2.65) and preterm (<37 weeks, aOR: 2.52, 95% CI 1.56–4.08) or very preterm delivery (<32 weeks, aOR: 7.02 95% CI 2.41–20.46) in subsequent pregnancies than women who did not have a history of RM. Conclusion: Women with a history of RM were twice as likely to undergo cesarean section and seven times more likely to deliver prior to 32 weeks of gestation than women without a history of RM. The study findings support the need for early pregnancy monitoring or assessment units to ensure better follow-up and customized care for at-risk pregnant women with a history of RM.</p
Patterns of tobacco smoking and nicotine vaping among university students in the united arab emirates: A cross-sectional study
Various forms of tobacco smoking and nicotine vaping tools are available on the market. This study quantified the prevalence of and identified factors associated with patterns of smoking and nicotine vaping among university students in the United Arab Emirates (UAE). A cross-sectional sample of students enrolled in three public universities was surveyed. Self-reported current smoking and nicotine vaping were recorded. Of 1123 students, 81.7% completed the online survey (mean age, 20.7 ± 3.4 (SD) years; 70.7% females). The prevalence of current smoking was 15.1% while the prevalence of current nicotine vaping was nearly 4.0%. Among current smokers, 54.7% reported conventional smoking only, 15.1% reported nicotine vaping only, and 28.8% were poly-users. Conventional midwakh (47.5%), followed by conventional shisha/waterpipe (36.7%), conventional cigarettes (36.7%), electronic shisha/waterpipe (25.2%), and electronic cigarettes (24.5%), were most commonly reported by students. Students aged 20–25 years (adjusted odds ratios (aOR): 2.08, 95% confidence interval (CI): 1.18–3.67) or \u3e25 years (aOR: 4.24, 95% CI: 1.41–12.80) had higher odds of being current smokers compared to those aged 17–19 years. The male gender was also independently associated with higher odds of being a current smoker (aOR: 5.45, 95% CI: 3.31–8.97) as well as higher odds of smoking cigarettes, shisha, and midwakh, or nicotine vaping compared to being female. Of nicotine vaping users, 36.1% reported using nicotine vaping because they enjoyed the flavor and vaporizing experience and 34.4% used it to help them to quit smoking. A relatively high prevalence of self-reported smoking was reported among university students in the UAE. The findings also suggest that nicotine vaping use is relatively widespread, but still less common than traditional smoking. Vigilant and tailored university-based smoking control and preventive measures are warranted
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