Design and Analysis of a Wide Stopband Microstrip Dual-band Bandpass Filter

A novel configuration of a dual-band bandpass filter (BPF) working as a harmonic attenuator is introduced and fabricated. The proposed filter operates at 3 GHz, for UHF and SHF applications, and 6.3 GHz, for wireless applications. The presented layout has a symmetric structure, which consists of coupled resonators. The designing of the proposed resonator is performed by introducing a new LC equivalent model of coupled lines. To verify the LC model of the coupled lines, the lumped elements are calculated. The introduced filter has a wide stopband up to 85 GHz with 28th harmonic suppression, for the first channel, and 13th harmonic suppression, for the second channel. The harmonics are attenuated using a novel structure. Also, the proposed BPF has a compact size of 0.056 λg2. Having several transmission zeros (TZs) that improve the performance of the presented BPF is another feature. The proposed dual-band BPF is fabricated and measured to verify the design method, where the measurement results confirm the simulations

Bishop score versus transvaginal ultrasonographic measurement of cervical length in predicting successful labor induction in post-term pregnancy: prospective cohort study

Background: The current study aims to compare the efficacy of Bishop score assessment and transvaginal ultrasonographic measurement of the cervical length in prediction of the outcome of labor induction in post-term pregnancy.Methods: A comparative Prospective observational study conducted in Department of Obstetrics and Gynecology, Kom Ombo central hospital from January 2017 to October 2017. Pregnant women were classified into two groups of Bishop Score Group (1): ladies with (Bishop Score 5) = favorable cervix. Also, they were classified into two groups of cervical lengths: Group (1): women with (cervical length <25mm, shorter cervix) and Group (2): those with (cervical length ≥25 mm, longer cervix). The Primary outcome was Bishop score by digital examination and Cervical length by TVS.Results: The study group was 100 women. Regarding sonographic assessment, 44 patients had cervical length <25 mm and the mean cervical length for the whole study group was 25.19±8.16 mm. Successful induction was achieved in 78 patients (78%), while CS was done in 22 patients due to failed induction.  No difference between both groups regarding the parity (p=0.063). When comparing women with successful VD versus those delivered by CS, we found significantly higher Bishop score in the first group 5.12 ± 1.93  vs 3.89 ± 1.71 in the second group (p=0.002). Additionally, VD group had significantly shorter cervix than CS group (22.31 ±7.14 vs. 35.37± 5.80 mm, p=0.007). The Bishop score showed significant moderate negative correlation with the cervical length (r=-0.589, p=0.001).Conclusions: Success of labor induction in women undergoing induction due to prolonged pregnancy can be highly predicted by cervical length as it is more objective and accurate than Bishop Score. The 25 mm cut-off point for cervical length was the best predictor of vaginal delivery

Uterine sparing approaches in management of placenta accreta: a summarized review

Placenta accreta is a potentially life-threatening obstetric condition that required multidisciplinary approach to management. Placenta accreta occurs in complete absence of the decidua basalis. Women with previous cesarean section delivery or placenta previa are known to be at greater risk of placenta accreta. A previous study reported that 24%& 67% increase in the incidence of placenta accreta in women 1 versus 3 or more previous cesarean deliveries respectively. Antenatal diagnosis of placental invasion has the potential to improve maternal and fetal outcomes. In practice, incomplete non-separation of the placenta at delivery leads to massive obstetric hemorrhage resulting in maternal morbidities such as massive blood transfusion, DIC, injury to the bladder and intestines and the need for hysterectomy. Sonographic examination with gray scale and color doppler imaging is the recommended first line modality for diagnosis of morbidly adherent placenta. Techniques developed for conservative management are techniques developed to preserve uterus and future fertility which is crucially linked to societal status and self-esteem

Studying the Effect of Addition of Carbon Black on Rheological Properties of Polypropylene and Polycarbonate

In the present research the rheological properties of polymer melt composed of (polypropylene- polycarbonate ) unfilled_ filled with different amounts of Iraqi carbon black (2 – 7) wt% was studied. Single screw extruder was used for development of these blends . The rheological behaviour of these blends was investigated by using rotational concentric type rheometer . The rheological properties shear rate( ( , apparent viscosity (a), dynamic viscosity(ή ), shear stress (τ) and angular frequency (ω),shearing flow at various temperatures ( 220 ˚C, 240˚C and 260 ˚C) were studied and found to be increase with increasing the amount of filler and decrease with increasing temperature. The flow curves were determined in the range of shear rate from about (10 to10 2 ) s-1. The activation energy was also measured, the values of activation energy varied from(11.939 to 20.892) KJ/Mole for different formation

A Compact Negative Group Delay Microstrip Diplexer with Low Losses for 5G Applications: Design and Analysis

Microstrip Diplexers play an important role in modern wireless communication systems. In this paper, a novel compact microstrip diplexer based on spiral cells is presented. The proposed resonator primarily consists of two spiral thin lines connected to a pair of coupled lines. This novel resonator is analyzed mathematically to find its behavior and tune the dimensions of the final layout easily. Using the analyzed resonator, two bandpass filters (BPFs) are designed. Then, a novel high-performance microstrip diplexer is obtained by designing and integrating these two BPFs. The center frequencies of the first and second channels of the proposed diplexer are 1.86 GHz and 4.62 GHz, respectively. The proposed diplexer boasts a remarkably small size of 0.004 λg2 and features flat channels with low insertion losses of only 0.048 dB and 0.065 dB for the first and second channels, respectively. The maximum group delays of S21 and S31 are 0.31 ns, 0.86 ns, respectively, which are good values for a modern communication system. Meanwhile, inside its passbands for some frequency ranges, its group delays are negative. Thus, using this diplexer can decrease the signal dispersion. The 1st and 2nd passbands are wide with 47.3% and 47.1% fractional bandwidths (FBW), respectively. Therefore, this diplexer can be easily and successfully used in designing high-performance RF communication systems

Propiedades y durabilidad de los cementos adicionados con metacaolín

This paper evaluates the optimal calcination temperature and replacement ratio to ensure high metakaolin (MK) pozzolanicity in blended cement. The MK used was prepared by firing two types of local at temperatures ranging from 700 to 850 ºC. Dry blends of ordinary Portland cement (OPC) and varying proportions of MK were mixed with the amount of water required to ensure optimal consistency of the resulting pastes. The specimens were cured at 100% RH for 24 h and then immersed in water for 3, 7, 28, 90 or 180 days. At each test time, the degree of hydration and compressive strength of the hardened cement pastes were measured The findings showed that the most suitable calcination temperature to obtain metakaolin is 700 ºC, while the optimal replacement ratio ranges from 25 to 30%. DTA was used to determine the phases comprising the hydration products forming at the ages studied. Pure OPC and OPC-MK specimens were immersed in 3% NaCl and 5% MgSO4 solutions for 30, 90 and 180 days to measure their durability. The OPC-MK pastes immersed in the 3% NaCl solution were observed to be highly resistant to chloride attack.El presente trabajo evalúa el comportamiento puzolánico de metacaolín (MK), producto de la calcinación a distintas temperaturas de dos tipos de caolín local de composiciones químicas diferentes, al incorporarse al cemento en diferentes proporciones. Se preparó un cemento adicionado mediante la mezcla en seco de cemento Portland ordinario (OPC) y metacaolín (MK), a los que se añadió la cantidad óptima de agua para obtener una pasta de la consistencia deseada. Las probetas se curaron a una HR del 100% durante 24 horas, sumergiéndose posteriormente en agua durante 3, 7, 28, 90 o 180 días. A cada tiempo de ensayo se controló el grado de hidratación de las pastas endurecidas y se comprobó la resistencia a la compresión de las probetas cúbicas a las edades de curado establecidas. Los resultados obtenidos indican que la temperatura más adecuada para la calcinación del caolín es de 700 °C y que el porcentaje óptimo de éste en la mezcla se encuentra entre el 25 y el 30%. Las fases que componen los productos resultantes de la hidratación se identificaron mediante ATD a distintas edades de curado. Se estableció la durabilidad del OPC puro y de las mezclas de OPC-MK en disoluciones de NaCl al 3% y MgSO4 al 5% tras 30, 90 y 180 días de inmersión. Se concluyó que las pastas de OPC-MK muestran una elevada resistencia al ataque del ion cloruro

Propiedades y durabilidad del cemento con adición de metacaolín: mortero y hormigón

This article explores the effect of metakaolin, a pozzolan, on concrete performance. Compressive and splitting tensile strength were found for specimens cured for up to 360 and 90 days, respectively. Changes were recorded in the compressive strength of specimens exposed to salt (chloride and sulfatechloride solutions), and chloride penetration and binding capacity were measured. The findings were compared to the results for concrete prepared with ordinary Portland (OPC) and moderate heat of hydration (Type II) cement. MK was found to have a very positive effect on 28-day concrete strength, due to microstructure improvement of the hydrated cement. Replacing cement with metakaolin effectively raised concrete resistance to chloride attack. Concrete containing metakaolin proved to be substantially more durable in sulfate-chloride environment.En este trabajo se estudia el efecto del metacaolín sobre las prestaciones del hormigón. Las probetas curadas a 360 y 90 días se sometieron a ensayos de resistencia a compresión y de tracción indirecta respectivamente. Se hizo un seguimiento de la resistencia a la compresión de los materiales ante el ataque de sales (soluciones de cloruro y de sulfato-cloruro) y, se midió la penetración de cloruros y la capacidad de los hormigones de inmovilizar estos iones. Los resultados se compararon con los obtenidos con hormigones elaborados con cemento pórtland ordinario (OPC) y, con cemento de calor de hidratación moderado (tipo II). El MK resultó influir muy positivamente en la resistencia del hormigón a 28 días debido a la mejora de la microestructura del cemento hidratado. La sustitución de cemento por metacaolín aumentó la resistencia del hormigón al ataque de cloruros. El hormigón con metacaolín demostró ser más duradero en entornos de sulfato-cloruro que los hormigones elaborados con OPC o con cemento de tipo II. Los perfiles de concentración de cloruros a distintas profundidades y la diferencia entre los contenidos de cloruro libre y total, mostraron claramente que el cemento con metacaolín reducía la penetración de cloruros en el hormigón y, aumentaba su capacidad para combinar con iones cloruro. La conclusión general fue que podía fabricarse material puzolánico utilizable, mediante la activación térmica del caolín local

Evaluation of the gas turbine unit in the Kirkuk gas power plant to analyse the energy and exergy using ChemCad simulation

The purpose of the study is to evaluate the thermal performance of the gas turbine unit represented by (K3) under actual weather conditions by applying the first and second laws of thermodynamics, the design production of the unit (283.6 MW) at standard conditions (1 bar) and temperature (15) Celsius, which included the analysis of the unit energy and available energy. Hence, to find out the weaknesses and losses in the system ChemCad simulation has been used to estimate the effects of external factors (ambient temperature, compression ratio and relative humidity) for a whole year on the performance of the turbine unit. Overall results showed that the maximum exergy efficiency was obtained in November; it was ∼37% when Ta was 19.39◦C. The maximum efficiency obtained at Ta equal to 19.39◦C, which was ∼37.67%. Higher ambient temperature increases specific fuel consumption (SFC). The results show that the SFC for the practical and program calculations increases with the increase in the temperature of the external environment and reached the maximum rate in the practical calculations in September (0.224) at 33.27◦C. Thus, it economically affects the price of power production. Moreover, the results showed that the combustion chamber occupied the first place for the destruction of available energy, and the results of energy efficiency and available energy were 39.20% and 30.83%, respectively. © The Author(s) 2022. Published by Oxford University Pres

Physical activity level and stroke risk in US population: A matched case-control study of 102,578 individuals

Background: Stroke has been linked to a lack of physical activity; however, the extent of the association between inactive lifestyles and stroke risk has yet to be characterized across large populations. Purpose: This study aimed to explore the association between activity-related behaviors and stroke incidence. Methods: Data from 1999 to 2018 waves of the concurrent cross-sectional National Health and Nutrition Examination Survey (NHANES) were extracted. We analyzed participants characteristics and outcomes for all participants with data on whether they had a stroke or not and assessed how different forms of physical activity affect the incidence of disease. Results: Of the 102,578 individuals included, 3851 had a history of stroke. A range of activity-related behaviors was protective against stroke, including engaging in moderate-intensity work over the last 30 days (OR = 0.8, 95% CI = 0.7-0.9; P = 0.001) and vigorous-intensity work activities over the last 30 days (OR = 0.6, 95% CI = 0.5-0.8; P \u3c 0.001), and muscle-strengthening exercises (OR = 0.6, 95% CI = 0.5-0.8; P \u3c 0.001). Conversely, more than 4 h of daily TV, video, or computer use was positively associated with the likelihood of stroke (OR = 11.7, 95% CI = 2.1-219.2; P = 0.022). Conclusion: Different types, frequencies, and intensities of physical activity were associated with reduced stroke incidence, implying that there is an option for everyone. Daily or every other day activities are more critical in reducing stroke than reducing sedentary behavior duration

Coherent diffraction of single Rice Dwarf virus particles using hard X-rays at the Linac Coherent Light Source

Single particle diffractive imaging data from Rice Dwarf Virus (RDV) were recorded using the Coherent X-ray Imaging (CXI) instrument at the Linac Coherent Light Source (LCLS). RDV was chosen as it is a wellcharacterized model system, useful for proof-of-principle experiments, system optimization and algorithm development. RDV, an icosahedral virus of about 70 nm in diameter, was aerosolized and injected into the approximately 0.1 mu m diameter focused hard X-ray beam at the CXI instrument of LCLS. Diffraction patterns from RDV with signal to 5.9 angstrom ngstrom were recorded. The diffraction data are available through the Coherent X-ray Imaging Data Bank (CXIDB) as a resource for algorithm development, the contents of which are described here.11Ysciescopu