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Bulk photovoltaic (BPVE) effect in crystals lacking inversion symmetry offers great potential for optoelectronic applications due to its unique properties such as above bandgap photovoltage and switchable photocurrent. Because of their large spontaneous polarizations, ferroelectric materials are ideal platforms for studying BPVE. However, identifying the origin of experimentally observed photovoltaic response is often challenging due to the entanglement between bulk and interface effects, leading to much debate in the field. This issue is particularly pronounced in vertical heterostructures, where the two effects are comparable. Here we report a crossover between bulk- and interface-dominant response in vertical BiFeO3 heterostructures when changing the photon energy. We show that well above-bandgap excitation leads to bulk photovoltaic response, but band-edge excitation requires interface band bending to separate the photocarriers. Our findings not only help to clarify contradicting reports in the literature, but also lay the ground for a deeper understanding of ferroelectric photovoltaic effect and its applications in various devices., ferroelectric photovoltaic effect, bulk photovoltaic effect, optical linear dichroism, BiFeO3

The purpose of this study is to demonstrate the impact of incorporating two different types of green nanomaterials (sugarcane and eggshell) on destructive and non-destructive properties of mortar. Nano sugarcane (NSC) was manufactured by calcining sugarcane at temperatures of 600 °C for 3 h. On the other hand, nano eggshell (NES) was manufactured by calcining eggshell at temperatures of 600 °C for 6 h. The sugarcane ash and eggshell ash were then milled to nano size. The final nano-sized product replaced Portland cement with different dosages of 2, 4 and 6%. Sixteen mortar mixtures were designed and prepared using only NSC or only NES or a combined hybrid of NSC and NES. Consistency, compressive strength, flexural strength and microstructure analysis (scanning electron microscopy and energy-dispersive X-ray) tests were conducted to investigate the influence of replacement materials on the performance and properties of mortars. The results showed that the use of nano sugarcane and nano eggshell enhanced the compressive strength and reduced permeability of green mortar due to the micropore structure. At the ages of 7 and 28 days, mortars containing a replacement ratio of 2% (0.5% NSC + 1.5% NES) had remarkably improved mechanical properties, and the improvement in compressive strength reached 21.3% and flexural strength to 10.08% when compared to the control sample. The efficiency of NSC and NES in increasing mortar strength was also confirmed by microstructure analysis.

Aim of the work To evaluate the effectiveness and advantages of automated CT volumetry in the assessment of liver volume in living donor liver transplantation and to compare this technique and its results with those calculated from manual volumetry. Materials and Methods This comparative study was conducted on dynamic contrast enhanced hepatic CT scans of 21 potential living liver donors. All potential donors underwent 1st step laboratory investigations to enter the 2nd step investigations for living donor liver transplantation operation. Automated liver volumetry was developed using the Myrian® XP-Liver software. To establish reference standard liver volumes, a radiologist manually traced the contour of the liver on each CT slice. We compared the results obtained with automated with those obtained with the reference standard for this study, manual volumetry. Results The study showed that automated CT liver volumetry achieved excellent agreement with manual volumetry without statistical significance. The average processing times for automated volumetry was 3.09 ± 0.44 min/case, whereas those for manual volumetry were 16.23 ± 0.81 min/case, the difference was statistically significant (p < 0.05). Conclusion Automated CT liver volumetry performed using the Myrian® XP-Liver software can accurately predict the preoperative liver volume and provide acceptable measurements comparable to the gold standard manual volumetry.

Background Invasive mechanical ventilation (IMV) for management of chronic obstructive pulmonary disease (COPD) associated respiratory failure is increasing in Intensive Care Units. The bridging process from IMV to extubation is called weaning in which mechanical ventilation is gradually withdrawn and the patient resumes spontaneous breathing. Many objective parameters have been defined for weaning success. The following review focuses on the different weaning methods in patients chronic obstructive pulmonary disease with respiratory failure. Objective To compare among the different methods of weaning in chronic obstructive pulmonary disease patients with respiratory failure weaned with different method ie BIPAP, CPAP and T-Piece. Patients and Methods Cross sectional descriptive study. 60 patients diagnosed as COPD with respiratory failure on MV, will be recruited from ICU Department Zefta general hospital. This study included 60 patients with acute exacerbation of chronic obstructive pulmonary disease (COPD) with age more than18 years old admitted in adult ICU Department in Zefta general hospital that are on mechanical ventilation. These patients fulfilled the inclusion criteria of the study. Patients were classified randomly into 3 groups. Results In this study I try to overcome these challenges by studying the effect of using of NIPPV both CPAP or BIPAP immediately after extubation or using T piece for 1 hour followed by extubation and using oxygen therapy that BIPAP improves patient gas exchange, hemodynamics and associated with shortest ICU stay which reflects on utilization of resources. Conclusion We suggest that BIPAP improves patient gas exchange specially in hypercapnic patients, hemodynamics and associated with shortest duration of ICU stay and decrease rate of reintuabtion.

Field experiments were carried out at Sakha Agricultural Research Station in Egypt to compare the effect of the newly developed raised bed technique with different bed widths (RB130, RB100, RB80 cm) on wheat productivity to the conventional flat basin (FB) method during 2019/2020. The statistical analyses were carried out using a randomized complete block design. According to the results of statistical analysis, using RB130 cultivation gave the highest significant averages of water-saving (21.81%) and the highest averages of wheat 1000 kernels weight (50.05 g) over the FB method. However, no significant differences were found between RB130 and FB method, which produced the highest averages of grain yield, straw yield, and biological yield. Wheat sowing on FB gave the highest significant average of grain yield, straw yield, and biological yield than RB100, RB80 at 5% level of significance, but there were no significant differences in the number of kernels per spike, kernel weight spike, and harvest index ratio between wheat sowing on FB and RB130, RB100 or RB80. There were no significant differences in the number of kernels per spike, kernel weight spike, number of spikes per m2, straw yield, biological yield, and harvest index ratio at 5% level of significance between wheat sowing on RB130, RB100, RB80. But wheat sowing on RB130 produced the highest significant average of crop water productivity and grain yield than RB80 at 5%. Finally, according to the study findings, using raised beds cultivation resulted in saving irrigation water by 15~21% compared to a flat basin.

Field experiments were carried out at the Sakha Agricultural Research Station in the governorate of Kafr el Sheikh, Egypt to evaluate and optimize the irrigation performance of raised beds wheat using the WinSRFR model during 2019/2020. Raised beds (RB130 cm, and RB100 cm) were prepared using Raised bed planter. The model calibration was based on a close match between the observed and simulated curves of advance and recession time. Simulation Analysis World was used to evaluate the current irrigation performance of the raised bed furrows (RB) and the flat basin (FB) methods. The simulation analysis shows that for RB130 cm, RB100 cm, and FB irrigation systems, the application efficiencies were 80, 64, 43%, and distribution uniformities were 86, 88, 90%, and deep percolation losses were 20, 36, 56%, and adequacy were 1.07, 1.37, 2.08%, respectively. Physical Design World was used to optimize and develop different design strategies. The results showed that irrigation performance decreased with the increasing length of furrow and basin, so extremely long lengths should be avoided because they result in decreased efficiency and uniformity, as well as big deep percolation loss. Managing the inflow rate and irrigation cut-off through Operation Analysis World can increase application efficiency and reduce deep percolation losses by more than 15%, 60%, and 17%, 33%, and 23%, 17.5% respectively, for RB130 cm, RB100 cm, and FB.

Inspired by the fascinating class of hybrid organic-inorganic halide perovskite materials, halide double perovskites have emerged as non-toxic Pb-free contenders for application as active layers in optoelectronic devices. Heterovalent substitution of Pb2+ by non-toxic metal cations yields the double-perovskite structure, which allows for compositional flexibility. In fact, the compositional space is large, given that multiple cations and halides can be combined, resulting in >106 perovskite combinations. A starkly increasing number of stable halide double-perovskite compositions are theoretically predicted. The synthesis, however, lags behind, and many double perovskites are primarily synthesized as powder samples instead of thin films. The latter, however, are needed for thin-film devices such as solar cells, light-emitting devices, and thin-film transistors. Comparing the synthetic approaches successfully applied to hybrid perovskites to methods used for the fabrication of double perovskites, the latter are clearly in their very infancy. The question is whether solution engineering and compositional modification strategies can be exploited to match the exceptional optoelectronic properties of hybrid perovskites. This review is motivated by a text mining effort that illustrates not only the prevalence of powder over thin-film synthesis but also the discrepancy between the number of compositions experimentally realized and studied and the many predicted compositions. Here we summarize the synthesis aspects of halide double perovskites, and in particular of thin films, including deposition techniques and synthetic modifications to alter film properties.

Postfabrication surface treatment strategies have been instrumental to the stability and performance improvements of halide perovskite photovoltaics in recent years. However, a consensus understanding of the complex reconstruction processes occurring at the surface is still lacking. Here, we combined complementary surface-sensitive and depth-resolved techniques to investigate the mechanistic reconstruction of the perovskite surface at the microscale level. We observed a reconstruction toward a more PbI2-rich top surface induced by the commonly used solvent isopropyl alcohol (IPA). We discuss several implications of this reconstruction on the surface thermodynamics and energetics. Particularly, our observations suggest that IPA assists in the adsorption process of organic ammonium salts to the surface to enhance their defect passivation effects.