Effect of fabrication technique on the crystalline phase and electrical properties of PVDF films

The effect of different fabrication techniques on the formation of electroactive beta-phase polyvinylidene fluoride (PVDF) has been investigated. Films with varying concentration of PVDF and solvent - dimethyl formamide (DMF) were synthesized by tape casting and solvent casting techniques. The piezoelectric beta-phase as well as non polar alpha-phase were observed for both the tape cast and solvent cast films from X-ray diffraction (XRD) micrographs and Fourier transform infra-red spectroscopy (FT-IR) spectra. A maximum percentage (80 %) of beta-phase was obtained from FT-IR analysis for a solvent cast PVDF film. The surface morphology of the PVDF films was analyzed by FESEM imaging. The dielectric properties as a function of temperature and frequency and the ferroelectric hysteresis loop as a function of voltage were measured. An enhancement in the value of the dielectric constant and polarization was obtained in solvent cast films

Higher levels of CO2 during late incubation alter the hatch time of chicken embryos

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Comparative study on ultrasonic placental grading among normotensive pregnancy and pregnancy-induced hypertension and its correlation with fetal outcome

Background: Placenta is essential for the fetal well-being, growth, and development which can be evidenced as early as possible through ultrasound at 6 weeks of gestation. The placenta mediates the intrauterine interaction between a mother and her baby. Aims and Objectives: This study aims to compare the pattern of placental grading among normotensive and pre-eclampsia mothers in a tertiary care hospital. Materials and Methods: This hospital-based observational analytical study has been conducted in the labor ward and outpatient department of the Department of Obstetrics and Gynaecology, Bankura Sammilani Medical College and Hospital from April 2021 to September 2022. A total of 69 pre-eclampsia mothers (study group) and 69 normotensive mothers (control group) who fulfill inclusion and exclusion criteria were included in the study. Template was generated and analysis was done on Statistical Package for the Social Sciences software. Results: A total of 138 pregnant women with 69 pregnant normotensive and 69 pregnant preeclampsia mothers were included in the study. The mean age of the study participants was 21.3 years (standard deviation=3.6). About 81.2% and 89.9% of the normotensive and hypertensive mothers, respectively, resided in rural areas. Cesarean/instrumental delivery was higher among the hypertensive pregnant women (42.0%) when compared to normotensive pregnant women (27.5%) and it was found to be statistically significant. Birth asphyxia was observed to be higher among the neonates in the hypertensive group (15.9%) when compared to the normotensive group (4.3%) and it was found to be statistically significant. Neonatal intensive care unit admission was more among the neonates of the mother with hypertension and it was found to be statistically significant. There was no significant difference in the birth weight of the newborn with the placental grading among the normotensive pregnant women. Conclusion: Ultrasonographic placental grading could be used as a screening tool for antepartum fetal surveillance in the obstetric population. Placental grading will help us to early diagnosis and to formulate line of management and timely intervention to reduce maternal and perinatal complications

Effect of transportation duration of 1-day-old chicks on postplacement production performances and pododermatitis of broilers up to slaughter age

This experiment studied the effect of transportation duration of 1-d-old chicks on dehydration, mortality, production performance, and pododermatitis during the growout period. Eggs from the same breeder flock (Ross PM3) were collected at 35, 45, and 56 wk of age, for 3 successive identical experiments. In each experiment, newly hatched chicks received 1 of 3 transportation duration treatments from the hatchery before placement in the on-site rearing facility: no transportation corresponding to direct placement in less than 5 min (T00), or 4 (T04) or 10 h (T10) of transportation. The chicks were housed in 35-m2 pens (650 birds each) and reared until 35 d old. Hematocrit and chick BW were measured on sample chicks before and after transportation. During the growout period, bird weight, feed uptake, and feed conversion ratio were measured weekly until slaughter. Transportation duration affected BW; T00 groups had a significantly higher BW than T04 and T10 transported birds but this effect lasted only until d 21. No clear effect on hematocrit, feed uptake, feed conversion ratio, or mortality was observed for birds transported up to 10 h. The decrease in weight in T10 birds was associated with less severe pododermatitis. Increasing age of the breeder flock was correlated with reduced egg fertility and hatchability, and also with higher quality and BW of hatched chicks. Chicks from older breeders also exhibited reduced mortality during the growout period

Generalized Flows around Neutron Stars

In this chapter, we present a brief and non-exhaustive review of the developments of theoretical models for accretion flows around neutron stars. A somewhat chronological summary of crucial observations and modelling of timing and spectral properties are given in sections 2 and 3. In section 4, we argue why and how the Two-Component Advective Flow (TCAF) solution can be applied to the cases of neutron stars when suitable modifications are made for the NSs. We showcase some of our findings from Monte Carlo and Smoothed Particle Hydrodynamic simulations which further strengthens the points raised in section 4. In summary, we remark on the possibility of future works using TCAF for both weakly magnetic and magnetic Neutron Stars.Comment: 15 pages, 7 figures. arXiv admin note: text overlap with arXiv:1901.0084

Wearable high-performance pressure sensors based on three-dimensional electrospun conductive nanofibers

Polymer-based pressure sensors play a key role in realizing lightweight and inexpensive wearable devices for healthcare and environmental monitoring systems. Here, conductive core/shell polymer nanofibers composed of poly (vinylidene fluoride-co-hexafluoropropene) (PVDF-HFP)/poly(3,4-ethylenedioxythiophene) (PEDOT) are fabricated using three-dimensional (3D) electrospinning and vapor deposition polymerization methods, and the resulting sponge-like 3D membranes are used to create piezoresistive-type pressure sensors. Interestingly, the PEDOT shell consists of well-dispersed spherical bumps, leading to the formation of a hierarchical conductive surface that enhances the sensitivity to external pressure. The sponge-like 3D mats exhibit a much higher pressure sensitivity than the conventional electrospun 2D mats due to their enhanced porosity and pressure-tunable contact area. Furthermore, large-area, wireless, 16 x 10 multiarray pressure sensors for the spatiotemporal mapping of multiple pressure points and wearable bands for monitoring blood pressure have been fabricated from these 3D mats. To the best of our knowledge, this is the first report of the fabrication of electrospun 3D membranes with nanoscopically engineered fibers that can detect changes in external pressure with high sensitivity. The developed method opens a new route to the mass production of polymer-based pressure sensors with high mechanical durability, which creates additional possibilities for the development of human-machine interfaces.11Ysciescopu