1,377 research outputs found
Carbon neutrality concept and progress
Sufficient scientific evidence now shows that Earth’s temperature is warmer than before. The temperature of the planet (global warming) is becoming s source of climate change that is estimated to have negative consequences for all living beings (Sovacool and Griffiths, 2020). Climate change, if it keeps moving in the direction in which it is heading now, will have severe consequences for anything and everything that exists on this planet. This is not a man-made story; rather, the argument is established upon the data collected by international organizations such as United Nations’ Intergovernmental Panel on Climate Change, Environmental Protection Agency, and NASA, among others. Data on global warming have been gathered across multiple time periods and analyzed for a very long time to arrive at the conclusion of severe and unpleasant consequences for everyone and everything on the planet. Excessive carbon dioxide emis- sions is the main contributing factor of global warming. However, it is not only carbon dioxide that causes global warming—many other gases are harmful to the climate, such as carbon dioxide, methane, and nitrous oxide, as well as hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride. This is not an exhaustive list, but for now, think of greenhouse gases as a catch-all term for the harmful substances we are pumping into the atmo- sphere. Since carbon dioxide has the most significant share among harmful gases, academic and nonacademic researchers study carbon dioxide more than other gases
Quantifying residues of insecticide applied for management of brinjal shoot and fruit borer
The experiment was undertaken to detect and quantify carbosulfan residues on brinjal fruit with comparison with maximum residue level (MRL) recommended by Food and Agricultural Organization (FAO). Carbosulfan was applied at the recommended rate of 1.5 ml·L-1 and the elevated rate of 3.0 ml·L-1 of water under tropical conditions. Samples were collected at different days after treatment (DAT) to determine presence, and degradation of, residues. A residue above the MRL was detected up to 3 DAT for the 1.5 ml·L-1 rate and 10 DAT for 3.0 ml·L-1 rate. Degradation shortly after application proceeded more slowly, but the rate of degradation increased over time. Carbosulfan is still legal for use on brinjal and it should not be applied above 1.5 ml·L-1 and the pre-harvest interval should not be less than 7 days
Association between disability measures and healthcare costs after initial treatment for acute stroke
<p><b>Background and Purpose:</b> The distribution of 3-month modified Rankin scale (mRS) scores has been used as an outcome measure in acute stroke trials. We hypothesized that hospitalization and institutional care home stays within the first 90 days after stroke should be closely related to 90-day mRS, that each higher mRS category will reflect incremental cost, and that resource use may be less clearly linked to the National Institutes of Health Stroke Scale (NIHSS) or Barthel index.</p>
<p><b>Methods:</b> We examined resource use data from the GAIN International trial comparing 90-day mRS with total length of stay in hospital or other institutions during the first 90 days. We repeated analyses using NIHSS and Barthel index scores. Relationships were examined by analysis of variance (ANOVA) with Bonferroni contrasts of adjacent score categories. Estimated costs were based on published Scottish figures.</p>
<p><b>Results:</b> We had full data from 1717 patients. Length of stay was strongly associated with final mRS (P<0.0001). Each mRS increment from 0 to 1–2 to 3–4 was significant (mean length of stay: 17, 25, 44, 58, 79 days; P<0.0005). Ninety-five percent confidence limits for estimated costs (£) rose incrementally: 2493 to 3412, 3369 to 4479, 5784 to 7008, 7300 to 8512, 10 095 to 11 141, 11 772 to 13 560, and 2623 to 3321 for mRS 0 to 5 and dead, respectively. Weaker relationships existed with Barthel and NIHSS.</p>
<p><b>Conclusions:</b> Each mRS category reflects different average length of hospital and institutional stay. Associated costs are meaningfully different across the full range of mRS outcomes. Analysis of the full distribution of mRS scores is appropriate for interpretation of treatment effects after acute stroke and more informative than Barthel or NIHSS end points.</p>
Improved Vivaldi Antenna with Radiation Pattern Control Features
Vivaldi antenna has been considered as a mitigation to the scattering effect of an antenna. However, the current performance of Vivaldi antenna suffers from multipath effect, interfering signals and radiation pattern control. This paper proposed an improved Vivaldi antenna which combined triple radiating slot to enable control of radiation pattern features. This is accomplished by controlling the position of the radiating element through the asymmetric arrangement of ideal switches to steer the beam in three desired-directions. The Using operating frequency lied between 900 MHz and 2.5GHz, the proposed design was fabricated and tested. Depending on the radiating element, the proposed antenna covered about ±90º with an almost equal gain at the three different focal in contrast to ±45º coverage of traditional rectangular microstrip antenna beam. The results satisfied pattern reconfigurability and the proposed design can be very useful for wireless communications where multipath fading problems are frequently encountered
Finite Element Analysis of Slab and a Comparative Study with Others Analytical Solution
Slabs are one of the most widely used structural elements. The function of slabs is to resist
loads normal to their plane. In many structures, in addition to support transverse load, the
slab also forms an integral portion of the structural frame to resist lateral load. Inspite of
their widespread use, there has never been a universally accepted method of designing all
slabs systems. The paper presents finite element analysis of slabs. The finite element method
is chosen as this is more powerful and versatile compared to other numerical methods. A slab
element is developed on the basis of conventional slab theory expressed in terms of
rectangular co-ordinates and displacement. The element incorporates 20 degree of freedom,
namely, normal displacement with its first derivatives along longitudinal and transverse
direction respectively and two tangential displacements. A computer program is developed
for solution of finite element equations as well as to check rigid body modes and to obtain the
results. The results are compared with analytical solution and previously developed finite
element solution with the help of a table
CP violation in the decay mode
Within the framework of Standard Model, the exclusive decay mode is studied. Although the usual short distance contribution is
small compared to the similar mode, the process offers the
possibility of studying the CP violation, a feature absent in the
counterpart.Comment: 11 page latex file including 2 ps figures. Typos corrected, minor
changes. To appear in PR
Improvement of third-order intermodulation product of RF and microwave amplifiers by injection
This paper discusses the improvement in the third-order intermodulation product (IM3) performance obtainable from RF and microwave amplifiers by two alternative injection techniques. The first is the addition to the amplifier input of the second harmonics of the input spectrum and the second is the addition to the amplifier input of the difference frequencies between the spectral components of the input signal. Both techniques are considered in theory, by simulation and in practice. Both techniques give useful improvements in two-tone IM3 performance. The second harmonic technique reduced the IM3 level by 43 dB in an amplifier at 835 MHz. The difference-frequency technique gave a reduction of 48 dB in an amplifier at 880 MHz. The difference-frequency technique also gives a greater improvement for complex spectra signal
Therapeutic effects of Laser and L-carnitine against amiodarone-induced pulmonary toxicity in adult male rats
Purpose: To compare the effects of laser and/or L-carnitine (LC) on amiodarone (AM)-induced lung toxicity in adult male rats.Methods: Lung toxicity was induced in 50 healthy male albino rats (150-180 g) by AM for 8 weeks. The rats were divided into 4 groups (7 per group): AM recovery, LC, laser, and laser + LC. After a 4-week exposure to laser and/or LC, key antioxidant enzymes, nitric oxide (NO), angiotensin II, cyclooxygenase-II (COX-II) and lipoxygenase (LOX) as well as oxidative stress and inflammation parameters were determined.Results: Administration of LC and/or laser exposure led to significant increases in reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT) and angiotensin II; and significant decreases in nitric oxide (NO) level and glutathione-S-transferase (GST) activity in the AM-treated rats when compared with the AM recovery group (p ˂ 0.05). The LC and/or laser exposure also significantly inhibited COX II and LOX activities in the lungs, and brought about significant reduction in levels of TNF-α and lipid peroxidation (LPO), and significant increases in cytochrome levels (p ˂ 0.05).Conclusion: These results indicate that AM induced pulmonary fibrosis in rats. However, AM withdrawal and treatment by LC and/or exposure to laser exerted mitigating effects against the AMinduced fibrosis.Keywords: Amiodarone, Lung toxicity, Laser; L-carnitin
Paper Review: Flutter Phenomenon in Aero-Elasticity
Flutter is aero-elasticity phenomenon concerning the analysis of the relationship among aerodynamic and elastic forces, aerodynamic forces (static-aeroelasticity). Inertia, elastic and aerodynamic forces (dynamic-aeroelasticity). Elastic forces and laws of control (aero-servo-elasticity). Modern airplane designs can be very versatile and this versatility of the airframe allows aero-elastic analysis an essential part of airplane construction and Procedures for validation. Torsional and wing flutter are the two major aero-elastic phenomena considering in airplane architecture. Hopf bifurcation is a instability case that happens when the torsional stiffness of the system is counteracted by static aerodynamic impact. Flutter is a fluctuating motion due to instability in aero-elastic influences defined by a continuous fluctuation of the system resulting from the interaction among the inertial, elastic and aerodynamic forces operating on the entire body. This article provides a better understanding for flutter phenomena and aero-elasticity issues that seek to offer readers an understanding of the topic
THERMAL EXPANSION BEHAVIOR OF THE Ba0.2Sr0.8Co0.8Fe0.2O3−δ (BSCF) WITH Sm0.2Ce0.8O1.9
Nanostructured perovskite oxides of Ba0.2Sr0.8Co0.8Fe0.2O3−δ (BSCF) were synthesized through the co-precipitation method. The thermal decomposition, phase formation and thermal expansion behavior of BSCF were characterized by thermogravimetric analysis, X-ray diffraction (XRD), and dilatometry, respectively. XRD peaks were indexed to a cubic perovskite structure with a Pm3m (221) space group. All the combined oxides produced the desired perovskite-phase BSCF. The microstructures were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The TEM analysis showed that BSCF powders had uniform nanoparticle sizes and high homogeneity. The cross-sectional SEM micrograph of BSCF exhibited a continuous and no delaminated layer from the electrolyte-supported cell. The thermal expansion coefficient (TEC) of BSCF was 16.2×10-6 K-1 at a temperature range of 600°C to 800°C. Additional experiments showed that the TEC of BSCF is comparable to that of Sm0.2Ce0.8O1.9 (SDC) within the same temperature range. The results demonstrate that BSFC is a promising cathode material for intermediate-temperature solid-oxide fuel cells
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