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The present research work reveals the electrical relaxation and conduction mechanism of CeO2 modified 0.92(Bi0.5Na0.5TiO3)-0.08(BaTiO3) ceramic (named as BNT-8BT-xCe; x = 0.0 ≤ x ≤ 0.04) synthesized by solid-state sintering method. The structural investigation using X-ray diffraction (XRD) pattern and Rietveld refinement confirms that dual phases of rhombohedral and tetragonal were maintained in all the samples. The non-linear shifting of peaks and the unit cell volume indicates the different site occupancy of Ce ions in the BNT-8BT ceramic. The modification in the microstructure also indicates the different site occupancy of the dopant. The frequency and temperature variant relaxation and conduction mechanism were analyzed using impedance spectroscopy. The variation in the real part of the impedance and the nature of the imaginary part of the impedance highlights the different roles of the Ce in BNT-8BT ceramic. The Nyquist plot shows the NTCR (negative temperature coefficient of resistance) behavior in all compositions and the grain and grain boundary resistance values were figured out using a suitable model. The frequency variant ac conductivity was fitted with power law equations and the fitting parameters were analyzed. The activation energy associated with the relaxation and conduction mechanism was obtained from the Arrhenius equations. All the obtained parameters were correlated to the impact of Ce in the BNT-BT ceramic. [ABSTRACT FROM AUTHOR]

The Indian diaspora, comprised of Non-Resident Indians (NRIs) and Persons of Indian Origin (PIOs), extends globally, transcending borders and unifying through shared identity, ethnicity, and cultural ties. This paper explores the evolving role of diasporas as economic contributors and development agents. It highlights the vastness of the Indian diaspora, with millions residing abroad, driven by various motivations. The historical roots of Indian migration, from ancient dispersals to modern movements, are discussed. In this paper, a comprehensive overview of the Indian diaspora spanning historical, geographical, and sociocultural dimensions is presented. The paper underlines the importance of diasporic contributions to literature, culture, and societal development, emphasizing the unique narratives of each diaspora group. It acknowledges that the Indian diaspora continues to evolve and grow, with opportunities and challenges still awaiting exploration in diaspora studies. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs), in which metal clusters are coupled by organic moieties, exhibit inherent porosity and crystallinity. Although these systems have been examined for vast potential applications, the elementary proton conduction in anhydrous MOFs still remains elusive. One of the approaches to deal with this problem is the utilization of protic organic molecules, to be accommodated in the porous framework. In this work we report the temperature-dependent crystal structure and proton conduction in [C2H5NH3][Na0.5Fe0.5(HCOO)3] metal–organic frameworks using X-ray diffraction and broadband dielectric spectroscopic techniques. The detailed analysis of the crystal structure reveals disorder of the terminal ethylene groups in the polar phase (space group Pn). The structural phase transition from Pn to P21/n at T≈ 363 K involves the distortion of the metal formate framework and ordering of EtA+ cations due to the reduction of the cell volume. The dielectric data have been presented in the dynamic window of permittivity formalism to understand the ferroelectric phase transition. The relaxation times have been estimated from the Kramers–Kronig transformation of the dielectric permittivity. A Grotthuss type mechanism of the proton conduction is possible at low temperatures with the activation energy of 0.23 eV. This type of experimental observation is expected to provide new prospective on the fundamental aspect of elementary proton transfer in anhydrous MOFs. [ABSTRACT FROM AUTHOR]

The fundamental aspects of the relaxation dynamics in niccolite-type, mixed valence metal–organic framework, multiferroic [(CH3)2NH2][Fe3+Fe2+(HCOO)6] single crystals have been reported using dielectric relaxation spectroscopy covering eight decades in frequency (10−2≤f≤ 106) in the temperature range 120 K ≤T≤ 250 K. The compound shows antiferroelectric to paraelectric phase transition near T = 154 K with the relaxor nature of electric ordering. The temperature dependent dielectric response in modulus representation indicates three relaxation processes within the experimental window. The variable range hopping model of small polarons explains the bulk non-Debye type conductivity relaxation. The fastest relaxation with activation energy Ea = 0.17 eV is related to progressive freezing of the reorientation motions of DMA+ cations. X-ray diffraction data revealed that complete freezing of orientational and translational motions of DMA+ cations occurs well below phase transition temperature. These experimental observations are fundamentally important for the theoretical explanation of relaxation dynamics in niccolite-type metal–organic frameworks. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs), in which metal clusters are coupled by organic moieties, exhibit inherent porosity and crystallinity. Although these systems have been examined for vast potential applications, the elementary proton conduction in anhydrous MOFs still remains elusive. One of the approaches to deal with this problem is the utilization of protic organic molecules, to be accommodated in the porous framework. In this work we report the temperature-dependent crystal structure and proton conduction in [C 2 H 5 NH 3 ][Na 0.5 Fe 0.5 (HCOO) 3 ] metal-organic frameworks using X-ray diffraction and broadband dielectric spectroscopic techniques. The detailed analysis of the crystal structure reveals disorder of the terminal ethylene groups in the polar phase (space group Pn). The structural phase transition from Pn to P2 1 /n at T ≈ 363 K involves the distortion of the metal formate framework and ordering of EtA + cations due to the reduction of the cell volume. The dielectric data have been presented in the dynamic window of permittivity formalism to understand the ferroelectric phase transition. The relaxation times have been estimated from the Kramers-Kronig transformation of the dielectric permittivity. A Grotthuss type mechanism of the proton conduction is possible at low temperatures with the activation energy of 0.23 eV. This type of experimental observation is expected to provide new prospective on the fundamental aspect of elementary proton transfer in anhydrous MOFs.

Objectives: There are many myths surrounding pregnancy and tuberculosis (TB), and outcome of treatment. This prospective study was conducted at the Department of Obstetrics and Gynecology, SCB Medical College, Cuttack, India, and at the authors' private clinics from 1986 to 2001 to determine the outcome of pregnancy if TB is treated properly., Methods: A total of 111 pregnant women diagnosed as having pulmonary and glandular TB were included in the study. They were matched for age, parity, and socioeconomic status with 51 pregnant women without TB (first control group), and 51 women with pulmonary TB but without pregnancy (second control group). The usual pregnancy management was given to the women in the study group, along with a short course of chemotherapy: either ethambutol, INH, or rifampicin and pyrazinamide for 2 months followed by INH and rifampicin for 4 months; or ethambutol, INH, and rifampicin for 2 months followed by INH and rifampicin for 7 months. Statistical analysis was done using a chi(2)-test., Results: There were no statistical differences in duration of gestation, preterm labor, and other complications of pregnancy, labor, and puerperium between the pregnancy groups. There were no congenital anomalies in the babies born to the groups. Pregnancy had no effect on the course of TB as regards sputum conversion, stabilization of the disease, and non-relapse even after 2-5 years of follow-up and a further delivery in a few cases., Conclusions: If proper and adequate chemotherapy is given to pregnant women with TB, they are not a higher risk than non-pregnant women with TB. Neither the disease nor chemotherapy is threatening to mother or newborn. However, today the ominous combination of human immunodeficiency virus, TB, and pregnancy poses a new challenge.

In spite of advancement of knowledge in diagnosis and management, tuberculosis is still the biggest health problem. There are more than 400 million people infected with tuberculous bacillus and more than 14 million cases are suffering from the disease. Prevention, control and care of tuberculosis are possible. General practitioners play a major role in combating the disease. Quick and right diagnosis and treating the cases effectively should be the motto. Sputum microscopy is the backbone of diagnosis of tuberculosis. With the availability of modern chemotherapy the outcome of a tuberculosis case has undergone dramatic changes. Short-course chemotherapy is the standard choice while tackling cases of tuberculosis. Results of directly observed treatment (DOT) strategy are very good provided execution is proper. HIV/AIDS, another dreaded disease if becomes co-infected along with tuberculosis, mortality and morbidity become very high. The general practitioners are the major strength of healthcare system in any society. They should be good enough to know all about the control programmes well implemented in the country.

In 150 cases of dysfunctional uterine bleeding the endometrial aspiration cytology was compared with histopathology in order to know the value of the former in such cases as the technique is found to be safe, simple, reliable and well accepted by patients as an outpatient department procedure. The material was adequate in 93% cases for cytology. It tallied 100% in tuberculosis and 94% in rest of the diseases with histopathology. Both the methods were equally effective in diagnosing and phasing the endometrium. But it becomes mandatory to follow up the cases where a malignant smear is not corroborated by histopathology.

Sixty-two cases of bacteriologically positive pulmonary tuberculosis were studied in the Department of Tuberculosis and Chest Diseases at the V.S.S. Medical College Hospital, Burla, India. Apart from other investigations, all patients underwent laparoscopy to determine the incidence of genital involvement. Positive findings were observed in 37 women; tubercles were present in the tubes of 15 women. At dilatation and curettage, the endometrium was obtained in 37 women. Tuberculous endometritis was detected in 4 women.

We studied 200 women with pulmonary tuberculosis to check for genital lesions: 13% of these women had genital tuberculosis. As clinical diagnosis was not possible, we relied on meticulous and repeated histopathologic studies. The occurrence of genital tuberculosis was more frequent in women who had pulmonary tuberculosis of shorter duration, but was not related to the severity of the disease. Pulmonary tuberculosis indirectly affects the female genital tract in almost all cases, giving rise to various gynecologic symptoms and signs. A review of the literature and further discussion about this subject are presented.