Effect of Zn Doping on Structural/Microstructural, Surface Topography, and Dielectric Properties of Bi2Fe4O9 Polycrystalline Nanomaterials.

In the present research work, bismuth ferrite mullite type Bi2Fe4-xZnxO9 (0.0 ≤ x ≤ 0.05) nanostructures are prepared by a chemical coprecipitation method and the effect of Zn doping concentration on the structural, surface topography, and dielectric properties is reported. The powder X-ray diffraction pattern of the Bi2Fe4-xZnxO9 (0.0 ≤ x ≤ 0.05) nanomaterial shows an orthorhombic crystal structure. Using Scherer's formula, the crystallite sizes of the nanomaterial Bi2Fe4-xZnxO9 (0.0 ≤ x ≤ 0.05) have been calculated and found to be 23.54 and 45.65 nm, respectively. The results of the atomic force microscopy (AFM) investigations show that spherical shape nanoparticles have grown and are densely packed around each other. AFM/scanning electron microscopy images, however, also illustrate that spherical nanoparticles transform into nanorod-like nanostructures with an increase in Zn concentrations. The transmission electron micrography images of Bi2Fe4-xZnxO9 (x = 0.05) showed elongated/spherical shape grains homogeneously distributed throughout the inside of the surface of the sample. The dielectric constants of Bi2Fe4-xZnxO9 (0.0 ≤ x ≤ 0.05) materials have been calculated and found to be 32.95 and 55.32. It is found that the dielectric properties improve with an increase in the Zn doping concentration, making it a good potential contender for multifunctional modern technological applications.

Dielectric study of Clove oil.

Dielectric properties of clove oil were determined using an impedance gain phase analyzer (HP 4194 A) at discrete frequencies between 10 kHz and 3 MHz and a range of temperature between 25 °C and 45 °C. A micro processor controller based temperature controller (Julabo F-25) was used for keeping the temperature of clove oil constant. Dielectric constant of the sample is found to decrease with increase in frequency and temperature, while dielectric loss decreases with increase in frequency but increases with increase in temperature. Penetration depth has been calculated with the help of dielectric data and is found to decrease with increase in frequency.

Multiphoton microscopy: a potential "optical biopsy" tool for real-time evaluation of lung tumors without the need for exogenous contrast agents.

CONTEXT: Multiphoton microscopy (MPM) is an emerging, nonlinear, optical-biopsy technique, which can generate subcellular-resolution images from unprocessed and unstained tissue in real time. OBJECTIVE: To assess the potential of MPM for lung tumor diagnosis. DESIGN: Fresh sections from tumor and adjacent nonneoplastic lung were imaged with MPM and then compared with corresponding hematoxylin-eosin slides. RESULTS: Alveoli, bronchi, blood vessels, pleura, smokers' macrophages, and lymphocytes were readily identified with MPM in nonneoplastic tissue. Atypical adenomatous hyperplasia (a preinvasive lesion) was identified in tissue adjacent to the tumor in one case. Of the 25 tumor specimens used for blinded pathologic diagnosis, 23 were diagnosable with MPM. Of these 23 cases, all but one adenocarcinoma (15 of 16; 94%) was correctly diagnosed on MPM, along with their histologic patterns. For squamous cell carcinoma, 4 of 7 specimens (57%) were correctly diagnosed. For the remaining 3 squamous cell carcinoma specimens, the solid pattern was correctly diagnosed in 2 additional cases (29%), but it was not possible to distinguish the squamous cell carcinoma from adenocarcinoma. The other squamous cell carcinoma specimen (1 of 7; 14%) was misdiagnosed as adenocarcinoma because of pseudogland formation. Invasive adenocarcinomas with acinar and solid pattern showed statistically significant increases in collagen. Interobserver agreement for collagen quantification (among 3 observers) was 80%. CONCLUSIONS: Our pilot study provides a proof of principle that MPM can differentiate neoplastic from nonneoplastic lung tissue and identify tumor subtypes. If confirmed in a future, larger study, we foresee real-time intraoperative applications of MPM, using miniaturized instruments for directing lung biopsies, assessing their adequacy for subsequent histopathologic analysis or banking, and evaluating surgical margins in limited lung resections.

Procalcitonin as the biomarker of inflammation in diagnosis of appendicitis in pediatric patients and prevention of unnecessary appendectomies.

Numerous diseases mimic appendicitis, and it is often difficult to rule it out on the basis of clinical presentation. Concentration of procalcitonin selectively increases in inflammatory conditions and determination of its level can help in the diagnosis of acute appendicitis. A prospective, single centre based observational study carried out at our tertiary care institute. Twenty eight patients were admitted with preliminary diagnosis of acute appendicitis. The control group involved around 12 healthy children. Serum Procalcitonin concentration was measured in all patients using the 'Immunoluminometric Method' (LUMI- Test PCT), besides carrying out clinical examination and other investigations. The serums PCT comes out to be a better diagnostic test than serum CRP measurement as serum PCT was able to differentiate patients who came with abdominal pain but were having normal appendix from the patients who were actual cases of acute appendicitis. In patients with histologically confirmed acute appendicitis the level of PCT was above the normal value of 0.5 ng/ml in most cases. The analysis of procalcitonin in different groups of patients showed the serum procalcitonin test having high sensitivity of 95.65% and a specificity of about 100% on the basis of histopathological diagnosis of the removed appendix taking as the standard. The serum procalcitonin test when combined with reliable clinical signs and symptoms is an excellent diagnostic marker of the disease and should be done in the patients of pediatric appendicitis so that proper handling of the patient can be done and we can prevent unnecessary appendectomies.