Five Layers Aurivillius Phases Pb2-xBi4+xTi5-xMnxO18: Synthesis, Structure, Relaxor Ferroelectric and Magnetic Properties

Synthesis of five layers Aurivillius phases, Pb2-xBi4+xTi5-xMnxO18 (0 "žT x "žT 1) were carried out by molten salts method using eutectic mixture of Na2SO4/K2SO4 salts (1:1 molar ratio) as the flux. The samples were characterized by X-ray diffraction powder and refined by Le Bail technique. The refinement results revealed that the samples with composition x = 0, 0.2, 0.4, and 0.6 formed five layers Aurivillius with the space group B2cb; however, the samples with x = 0.4 and 0.6 contained impurity as BiMnO3 and the additional phase of four layers Aurivillius (PbBi4Ti4O15) was also observed for x = 0.6. The samples with x = 0.8 and 1 resulted in two phases: four layers Aurivillius and BiMnO3. The dielectric properties of the Pb2-xBi4+xTi5-xMnxO18 show broad peaks with the temperature of the maximum of the dielectric constant (Tm) at temperature of 295, 295, 304, and 343"žaC at a frequency of 2 MHz for x = 0, 0.2, 0.4, and 0.6, respectively. The Tm of these samples is shift to the left with decreasing frequency as indication of relaxor ferroelectric behavior. The samples with x = 0.8 and 1 show anomaly at 514"žaC and 551"žaC which correspond to the transition phase of four layers Aurivillius. Magnetic properties for all samples containing Mn are paramagnetic

Magnetic field induced ferroelectric to relaxor crossover in Tb1-xCaxMnO3

The influence of magnetic field on the electrical properties of Tb1−xCaxMnO3 has been investigated by means of dielectric, polarization and neutron diffraction measurements. A field of 6 T applied along the b-axis induces a crossover from ferroelectric to relaxor behavior for the x = 0.02 compound at temperatures close to the ferroelectric transition. The mechanism of this field induced crossover involves a decrease in the coherence length of the Mn-spin-spiral structure due to increasing electron hopping rates associated with double exchange. Moreover, a large negative magnetocapacitance is observed at the freezing temperature for x = 0.05, which originates from suppression of the relaxor state and thus represents a new mechanism of magnetocapacitance.

Perkembangan Embrio Dan Penentuan Jenis Kelamin DOC (Day-Old Chicken) Ayam Jawa Super

Super Javanese chicken is the result of a cross breeding between male domestic chicken and female layer chicken. . There has not been much research aboutSuper Javanese chicken embryonic development. This study attempts to provide information about embryonic development and sexing on Super Javanese chicken. This study used Super Javanese chicken fertile eggs from Java Farm, Maguwoharjo, Depok, Sleman. These eggs were incubated at temperature of 37o-38oC. Samples were observed with Neutral Red and Hematoxilin Eosine (HE) staining. The measurement of the Super Javanese chicken embryo were about length of the third finger, beak, and the length of the embryo's body. This observation obtained embryonic development of the super Javanese chicken spesifically. This concluded that Super Javanese chicken as a first generation from cross breeding has slower growth in embryonic developmen

What brain abnormalities can magnetic resonance imaging detect in foetal and early neonatal spina bifida: a systematic review

PURPOSE: Open spina bifida (OSB) encompasses a wide spectrum of intracranial abnormalities. With foetal surgery as a new treatment option, robust intracranial imaging is important for comprehensive preoperative evaluation and prognostication. We aimed to determine the incidence of infratentorial and supratentorial findings detected by magnetic resonance imaging (MRI) alone and MRI compared to ultrasound. METHODS: Two systematic reviews comparing MRI to ultrasound and MRI alone were conducted on MEDLINE, EMBASE, and Cochrane databases identifying studies of foetal OSB from 2000 to 2020. Intracranial imaging findings were analysed at ≤ 26 or > 26 weeks gestation and neonates (≤ 28 days). Data was independently extracted by two reviewers and meta-analysis was performed where possible. RESULTS: Thirty-six studies reported brain abnormalities detected by MRI alone in patients who previously had an ultrasound. Callosal dysgenesis was identified in 4/29 cases (2 foetuses ≤ 26 weeks, 1 foetus under any gestation, and 1 neonate ≤ 28 days) (15.1%, CI:5.7-34.3%). Heterotopia was identified in 7/40 foetuses ≤ 26 weeks (19.8%, CI:7.7-42.2%), 9/36 foetuses > 26 weeks (25.3%, CI:13.7-41.9%), and 64/250 neonates ≤ 28 days (26.9%, CI:15.3-42.8%). Additional abnormalities included aberrant cortical folding and other Chiari II malformation findings such as lower cervicomedullary kink level, tectal beaking, and hypoplastic tentorium. Eight studies compared MRI directly to ultrasound, but due to reporting inconsistencies, it was not possible to meta-analyse. CONCLUSION: MRI is able to detect anomalies hitherto underestimated in foetal OSB which may be important for case selection. In view of increasing prenatal OSB surgery, further studies are required to assess developmental consequences of these findings

Impact of Covid-19 on Yamuna River water quality: Possible ways to rejuvenate the riverine ecosystem in national capital of India

The water quality of Yamuna River was studied for four years from 2019 until August 2022. The period witnessed the onset of COVID-19 pandemic and government-imposed complete lockdown which caused slight improvement in the water quality. Five parameters pH, Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Dissolved Oxygen (DO) and Faecal Coliform (FC) monitored by Delhi Pollution Control Committee (DPCC) were analyzed to see the changes in water quality of Yamuna River in the Delhi stretch before the onset of COVID-19 (2019), during the COVID-19 (2020 and 2021) and after the pandemic (2022). Maximum improvement in some water quality parameters were observed only during the 1st lockdown in the year 2020 when government had imposed complete restriction on the movement of people and industries were not functioning at there maximum capacity. The water quality again declined in the year 2021 and further in the year 2022. Major cause of pollution was the untreated waste reaching the river from various drains. Therefore, it is extremely important to intersect all the major and minor drains through Sewage Treatment Plants (STPs). The floodplain of the river needs to be managed to keep the pollution in control

Amustaline-glutathione pathogen-reduced red blood cell concentrates for transfusion-dependent thalassaemia

Transfusion-dependent thalassaemia (TDT) requires red blood cell concentrates (RBCC) to prevent complications of anaemia, but carries risk of infection. Pathogen reduction of RBCC offers potential to reduce infectious risk. We evaluated the efficacy and safety of pathogen-reduced (PR) Amustaline-Glutathione (A-GSH) RBCC for TDT. Patients were randomized to a blinded 2-period crossover treatment sequence for six transfusions over 8–10 months with Control and A-GSH-RBCC. The efficacy outcome utilized non-inferiority analysis with 90% power to detect a 15% difference in transfused haemoglobin (Hb), and the safety outcome was the incidence of antibodies to A-GSH-PR-RBCC. By intent to treat (80 patients), 12·5 ± 1·9 RBCC were transfused in each period. Storage durations of A-GSH and C-RBCC were similar (8·9 days). Mean A-GSH-RBCC transfused Hb (g/kg/day) was not inferior to Control (0·113 ± 0·04 vs. 0·111 ± 0·04, P = 0·373, paired t-test). The upper bound of the one-sided 95% confidence interval for the treatment difference from the mixed effects model was 0·005 g/kg/day, within a non-inferiority margin of 0·017 g/kg/day. A-GSH-RBCC mean pre-transfusion Hb levels declined by 6·0 g/l. No antibodies to A-GSH-RBCC were detected, and there were no differences in adverse events. A-GSH-RBCCs offer potential to reduce infectious risk in TDT with a tolerable safety profile

The Effect of Refractivity on Propagation at UHF and VHF Frequencies

This paper is using weather parameters to investigate the effect of refractivity on propagation in the first kilometer of the atmosphere over the English Channel for a long transhorizon path of 140 km. Different refractivity profiles are constructed based on meteorological data taken from the UK Meteorological Office in order to investigate the effects of refractivity on propagation. The analysis is made for the hourly experimental path loss between the transmitter and receiver obtained from the experimental setup comprised of two communication links. The frequency of operation of the first link is 2015 MHz and that of the second link is 240 MHz. Parabolic equation method is modelled to get an hourly modelled path loss corresponding to each hourly experimental path loss to be analyzed for the said communication links. The correlation between the modelled path loss and experimental path loss is computed for refractivity distribution recommended by the ITU and predicted profiles. It is inferred from the simulated and experimental results that little or no influence exists by the evaporation duct upon path loss at 2015 MHz specifically for a long path of 140 km over the sea