Change in the room temperature magnetic property of ZnO upon Mn doping

We present in this paper the changes in the room temperature magnetic property of ZnO on Mn doping prepared using solvo-thermal process. The zero field cooled (ZFC) and field cooled (FC) magnetisation of undoped ZnO showed bifurcation and magnetic hysteresis at room temperature. Upon Mn doping the magnetic hysteresis at room temperature and the bifurcation in ZFC-FC magnetization vanishes. The results seem to indicate that undoped ZnO is ferromagnetic while on the other hand the Mn doped ZnO is not a ferromagnetic system. We observe that on addition of Mn atoms the system shows antiferromagnetism with very giant magnetic moments.Comment: 5 figure

Odontogenic tumors: a review of 60 cases

Objective: Studies on odontogenic tumors published from many parts of the world show a distinct geographic va- riation; however, there is little information available in the English-language literature on the relative frequency of odontogenic tumors in India. This retrospective study was designed to determine the relative frequency of odonto- genic tumors in an Indian population and compare them with various reports from other parts of the world. Study design: The histopathology records of the Department of Oral pathology and Microbiology of Government Dental College and Hospital, Mumbai were retrieved retrospectively within the period of January 2001 to March 2010. A total of 60 lesions classified as odontogenic tumors were reviewed. These were analyzed for age, gender, site of tumor and histopathologic typing. Criteria used were World Health Organization (WHO) classification 2005. The controversy still exists regarding the nature of odontogenic keratocyst or tumor, so it has not been included in this study. Results: A total of 60 cases of odontogenic tumors were reported in this period. The most frequent histological type was ameloblastoma (66.67%), followed by odontome (20%), adenomatoid odontogenic tumor (10%). In general, the odontogenic tumors showed a predilection for the mandible and the posterior regions of the jaws. Ameloblastomas occurred with a marked predilection for the mandible, while adenomatoid odontogenic tumor showed predi- lection for the maxilla, anterior regions of the jaws, and young females. Conclusion: Odontogenic tumors show a definite geographic variation. In our study, ameloblastomas were the most frequent odontogenic tumors, with distinct anatomic predilection

Plexiform ameloblastoma of mandible: case report

Ameloblastoma, a benign epithelial odontogenic tumor, is locally aggressive. This tumor comprises about 1% of tumors and cysts arising in the jaws. It appears most commonly in the third to fifth decades and with equal frequency between sexes. Ameloblastoma prevalently occurs in the mandibular molar and the ramus areas. Recurrence frequently appears after inadequate treatment. They are usually benign in growth pattern but frequently invade locally and occasionally metastasize. In the present study, a case of unusually large plexiform ameloblastoma was presented with its clinical, radiological, histological features and treatment modalities, and this is the addition of one more case in the literature

Transient Local Bone Remodeling Effects of rhBMP-2 in an Ovine Interbody Spine Fusion Model

Background: Recombinant human bone morphogenetic protein-2 (rhBMP-2) is a powerful osteoinductive morphogen capable of stimulating the migration of mesenchymal stem cells (MSCs) to the site of implantation and inducing the proliferation and differentiation of these MSCs into osteoblasts. Vertebral end-plate and vertebral body resorption has been reported after interbody fusion with high doses of rhBMP-2. In this study, we investigated the effects of 2 rhBMP-2 doses on peri-implant bone resorption and bone remodeling at 7 time points in an end-plate-sparing ovine interbody fusion model. Methods: Twenty-one female sheep underwent an end-plate-sparing discectomy followed by interbody fusion at L2-L3 and L4-L5 using a custom polyetheretherketone (PEEK) interbody fusion device. The PEEK interbody device was filled with 1 of 2 different doses of rhBMP-2 on an absorbable collagen sponge (ACS): 0.13 mg (1·) or 0.90 mg (7·). Bone remodeling and interbody fusion were assessed via high-resolution radiography and histological analyses at 1, 2, 3, 4, 8, 12, and 20 weeks postoperatively. Results: Peri-implant bone resorption peaked between 3 and 8 weeks in both the 1· and the 7· rhBMP-2/ACS-dose group. Osteoclastic activity and corresponding peri-implant bone resorption was dose-dependent, with moderate-tomarked resorption at the 7·-dose level and less resorption at the 1·-dose level. Both dose (p \u3c 0.0007) and time (p \u3c 0.0025) affected bone resorption significantly. Transient bone-resorption areas were fully healed by 12 weeks. Osseous bridging was seen at all but 1 spinal level at 12 and at 20 weeks. Conclusions: In the ovine end-plate-sparing interbody fusion model, rhBMP-2 dose-dependent osteoclastic resorption is a transient phenomenon that peaks at 4 weeks postoperatively. Clinical Relevance: Using the U.S. Food and Drug Administration (FDA)-approved rhBMP-2 concentration and matching the volume of rhBMP-2/ACS with the volume of desired bone formation within the interbody construct may limit the occurrence of transient bone resorption

Bifurcation analysis of phytoplankton-fish model through parametric control by fish mortality rate and food transfer efficiency

An Algae-zooplankton fish model is studied in this article. First the proposed model is evaluated for positive invariance and boundedness. Then,the Routh-Hurwitz parameters and the Lyapunov function are used to determine the presence of a positive interior steady state and the criteria for plankton model stability (both local and global). Taylor’s sequence is also used to discuss Hopf bifurcation and the stability of bifurcated periodic solutions. The model’s bifurcation analysis reveals that Hopf-bifurcation can occur when mortality rate and food transfer efficiency are used as bifurcation parameters. Finally, we use numerical simulation to validate the analytical results

Water relations, growth, and dry matter accumulation of sorghum under post-rainy season conditions

Field studies were conducted on deep vertisols to assess the effects of water stress on the growth and DM accumulation of sorghum. Leaf water potential and stomatal conductance were measured diurnally on 4 dates during the growing season. Irrigated sorghum exhibited higher stomatal conductance, higher leaf water potentials, higher LAI and greater DM accumulation than non-irrigated sorghum. Higher transpiration rates in irrigated sorghum were explained by increased net radiation measured over the irrigated canopy. Lower leaves in the sorghum canopy showed lower stomatal conductance. Non-irrigated sorghum had fewer tertiary branches/secondary branch, fewer seeds/panicle and smaller seeds. Non-irrigated sorghum used 213 mm water to produce 0.51 kg DM/m2; irrigated sorghum extracted 321 mm water to produce 0.93 kg DM/m

Genetic and Epigenetic Alterations of Lysophosphatidic Acid Receptor Genes in Rodent Tumors by Experimental Models

Lysophosphatidic acid (LPA) is a bioactive mediator and induces several biological effects, including cell proliferation, migration, morphogenesis and differentiation. LPA interacts with at least six G protein-coupled receptors (GPCRs), including LPA receptor-1 (LPA1), LPA2, LPA3, LPA4, LPA5 and LPA6. These receptors show different biological functions through the binding of LPA, depending on the type of cells. In human malignancies, a high level of LPA production was found in plasma and ascites in ovarian cancer cases. Moreover, aberrant expression levels of LPA receptor genes were detected in some cancer cells. Therefore, it is suggested that LPA receptors may be involved in the pathogenesis of tumor cells as well as LPA per se. Recently, we have reported that alterations of LPA receptor genes also occur in rodent tumors. In this review, we summarize the recent evidence in the investigations of LPA receptor alterations in rodent tumors by experimental models

Effect of water deficit at different growth phases of peanut. I. Yield responses

Response of groundnut cv. Robut 33-1 to drought stress imposed at (a) emergence to maturity, (b) emergence to peg initiation, (c) from the start of flowering to the start of seed growth, and (d) from the start of seed growth to maturity was studied during the post-rainy seasons of 1980-81 and 1981-82. The amount of water applied during these phases was varied using line-source irrigation, but the crops otherwise were irrigated uniformly at regular intervals. The greatest reduction in seed yield (28-96%) occurred when stress was imposed during (d). Decreased irrigation during (b) increased pod yield relative to the fully irrigated control treatment by 19% in 1980-81 and 13% in 1981-82. The evapotranspiration-yield relationships showed a strong interaction with timing of drough

Correlation between the Josephson coupling energy and the condensation energy in bilayer cuprate superconductors

We review some previous studies concerning the intra-bilayer Josephson plasmons and present new ellipsometric data of the c-axis infrared response of almost optimally doped Bi_{2}Sr_{2}CaCu_{2}O_{8}. The c-axis conductivity of this compound exhibits the same kind of anomalies as that of underdoped YBa_{2}Cu_{3}O_{7-delta}. We analyze these anomalies in detail and show that they can be explained within a model involving the intra-bilayer Josephson effect and variations of the electric field inside the unit cell. The Josephson coupling energies of different bilayer compounds obtained from the optical data are compared with the condensation energies and it is shown that there is a reasonable agreement between the values of the two quantities. We argue that the Josephson coupling energy, as determined by the frequency of the intra-bilayer Josephson plasmon, represents a reasonable estimate of the change of the effective c-axis kinetic energy upon entering the superconducting state. It is further explained that this is not the case for the estimate based on the use of the simplest ``tight-binding'' sum rule. We discuss possible interpretations of the remarkable agreement between the Josephson coupling energies and the condensation energies. The most plausible interpretation is that the interlayer tunneling of the Cooper pairs provides the dominant contribution to the condensation energy of the bilayer compounds; in other words that the condensation energy of these compounds can be accounted for by the interlayer tunneling theory. We suggest an extension of this theory, which may also explain the high values of T_{c} in the single layer compounds Tl_{2}Ba_{2}CuO_{6} and HgBa_{2}CuO_{4}, and we make several experimentally verifiable predictions.Comment: 16 pages (including Tables) and 7 figures; accepted for publication in Physical Review