Rectification in Discharge Tubes

A detailed study of rectification phenomena in air following the earlier work of Chiplonkar is given. The effect in hydrogen and CO is also discussed. Recently Mr. Chiplonkar (1939) has made some quantitative investigations of the well-known phenomenon of rectification in discharge tubes. His work was mainly confined to the study of the precise role of the electrodes, their relative sizes and the inter-electrode distance in determining the rectification effect. This paper is an extension of Mr. Chiplonkar's work and deals with a detailed study of rectification phenomena in air. The effect in hydrogen and CO has also been partly studied

Connective tissue disorders in pregnancy: maternal and fetal perspective

Background: The objective of this study was to study maternal and fetal outcome in connective tissue disorders in pregnancy.Methods: This was a retrospective type of observational study done in department of obstetrics and gynecology and department of rheumatology at a King Edward Memorial hospital over a period of 1.5 years. 48 women were included in this study after informed consent. All these women presented with collagen disorders to ANC outpatient department or to rheumatology outpatient department or in emergency. All postpartum patients having connective tissue disorders not recruited during ANC were also included in this study after taking their written, informed and valid consent.Results: Connective tissue disorders are associated with multiple voluntary and involuntary abortions as well as intrauterine fetal deaths. Even in those women having live births, many undergo cesarean sections due to various indications like fetal distress, poor biophysical profile, non-reassuring non stress test etc. Neonates born to mothers with connective tissue disorders are growth restricted and many of them need intensive care admission. Also, these women were found to have multiple associated medical comorbidities in pregnancy.Conclusions: The data collected and the results arrived upon should help contribute significant literature regarding collagen disorders in pregnancy and help in better fetal and maternal management during pregnancy

Ultrasonographic measurement of uterine lower segment scar thickness in cases of previous one caesarean section and obstetric outcome

Background: Vaginal birth after caesarean section (VBAC) has become an integral part of modern obstetrics with more than 1lakh VBACs achieved each year nationwide. Several studies have reported perinatal risks associated with failed trial of labour and uterine rupture in women attempting VBAC, due to concerns about these complications, the rate of VBAC deliveries has continued to fall in developed countries, with an inverse increase in Caesarean Sections (CS). To better assess the risk of uterine rupture, many authors have proposed sonographic measurement of scar or lower uterine segment (LUS) thickness near term, assuming that there is an inverse correlation between LUS thickness and the risk of uterine scar defect. Therefore, this assessment for the management of women with prior CS has increased safety by selecting women with the lowest risk of uterine rupture.Methods: Present study was a prospective observational study which assessed the obstetric outcome in women with previous lower segment caesarean section willing for trial of labour. Secondly, authors aimed to ascertain the best cut off values for predicting uterine rupture.Results: Present study found that as duration between previous LSCS and next pregnancy increased there was better chance of VBAC. As the baby weight increased VBAC rate reduced. Study also showed that scar thickness of 2.55mm and above measured by transabdominal method in the third trimester can be safely given trial of VBAC.Conclusions: Authors thus conclude that measurement of lower uterine segment/ scar thickness can help obstetrician decide whether VBAC is safe or not in patients with previous one LSCS willing for VBAC. Scar thickness of more than 2.55mm can be given safe trial of labour in women with previous one lower segment caesarean section

Audit on maternal mortality in a tertiary care centre in India of 6 years, a retrospective analysis

Background: This study is carried out on 382 cases of maternal deaths from July 2010 to June 2016 at the department of obstetrics and gynaecology of tertiary centre to evaluate causes and risk factor associated with maternal deaths.Methods: Retrospective analysis of all maternal deaths occurred in department of obstetrics and gynaecology of tertiary care hospital from July 2010 to June 2016.Results: The MMR in the study period was 915/100000 live births. Maximum no. of maternal death 42.7% were in age group of 21-25 years, majority of them residing in urban area. 117 patients referred from sub-district/district hospital. 76.4% patients were registered. 60% maternal deaths were seen in postnatal period. In present study majority of maternal deaths 60% were due to indirect cause while 40% patients died due to direct cause. Major causes of maternal deaths were hypertensive disorder 12%, obstetric haemorrhage 11% tuberculosis 11%, hepatitis E 8% and pregnancy related infections 5.6%.Conclusions: High maternal mortality can be due to the fact that the study was conducted in tertiary care referral centre. Referral of moribund cases from rural, sub-district, district and peripheral hospital to our institute have inflated this mortality ratio. All of these being preventable causes of death can be avoided by improving standard of obstetric care, increasing number of health professionals, upgradation of healthcare facilities at first referral units and by making better health policies

Electronic states of PrCoO3_3: X-ray photoemission spectroscopy and LDA+U density of states studies

Electronic states of PrCoO$_3$ are studied using x-ray photoemission spectroscopy. Pr 3d$_{5/2}$ core level and valence band (VB) were recorded using Mg K$_\beta$ source. The core level spectrum shows that the 3d$_{5/2}$ level is split into two components of multiplicity 4 and 2, respectively due to coupling of the spin states of the hole in 3d$_{5/2}$ with Pr 4f holes spin state. The observed splitting is 4.5 eV. The VB spectrum is interpreted using density of states (DOS) calculations under LDA and LDA+U. It is noted that LDA is not sufficient to explain the observed VB spectrum. Inclusion of on-site Coulomb correlation for Co 3d electrons in LDA+U calculations gives DOS which is useful in qualitative explanation of the ground state. However, it is necessary to include interactions between Pr 4f electrons to get better agreement with experimental VB spectrum. It is seen that the VB consists of Pr 4f, Co 3d and O 2p states. Pr 4f, Co 3d and O 2p bands are highly mixed indicating strong hybridization of these three states. The band near the Fermi level has about equal contributions from Pr 4f and O 2p states with somewhat smaller contribution from Co 3d states. Thus in the Zaanen, Sawatzky, and Allen scheme PrCoO$_3$ can be considered as charge transfer insulator. The charge transfer energy $\Delta$ can be obtained using LDA DOS calculations and the Coulomb-exchange energy U' from LDA+U. The explicit values for PrCoO$_3$ are $\Delta$ = 3.9 eV and U' = 5.5 eV; the crystal field splitting and 3d bandwidth of Co ions are also found to be 2.8 and 1.8 eV, respectively.Comment: 12 pages, 7 figures; to appear J. Phys.: Condens. Matte

Pathophysiology of altered color perception

Human beings are able to perceive hundreds of shades of color which depends on the three types of cone system and various ratios of stimulation in response to different wavelengths. Perceptually and cognitively, men and women may experience appearance of color differently. The convention seems to be that women tend to prefer brighter and gratifying colors and men are more comfortable with stifled and soft colors. The reason may be linked to hormonal, developmental and environmental differences amongst both the sexes. The present review discusses various types of clinical and experimental studies done on alteration in color perception

Game Theoretic Approach for Cognitive Radio Networks

Cognitive radio is a promising approach to make efficient use of spectrum by rapidly adapting the changes in wireless environment. In such networks, nodes are expected to be aware of their environment and must be able to learn from the outcomes of past decisions. Game theory which comprise of analytical tools designed to study interactive decision-making processes can be applied effectively to solve some of such complex problems. This paper discusses the significance of using game theory for cognitive radio networks and resource allocation, and various game theoretic approaches used for it. DOI: 10.17762/ijritcc2321-8169.15059