9,334 research outputs found

    TERMITE FAUNA OF KRAKATAU AND ASSOCIATED ISLANDS, SUNDA STRAITS, INDONESIA

    Get PDF
    Frequent volcanic eruptions, submergence and emergence of some of theIndonesian islands has made them ail object of intense biogeographical significance. These geological catastrophies resulted in complete sterilization of the area biologically, wiping out all forms of life. Subsequent reuegetation and establishment of new fauna attracted many scientists, some of them having made very significant contributions.The present contribution deals with termite fauna of Krakatau and associated islands. In all, twenty five species and 13 genera, the highest number so far reported, from Carita (9 species), Panaitan Islands (6 species), Rahota Besar (2 species), Anak Krakatau and Sertung (1 species each) have been recorded in this publication. Of these, while, Prorhinotermes panaitanensis is new to science, two species (Glyptotermes besarensis and G. panaitanensis) have been described recently by the senior author (MLT). Similarly Glyptotermes minutus, Nasutitermes culasiensis and Hospitalitermes buzpnensis have been recorded for the first time from the Indonesia. Several other species are new distributional records. Nasutitermes matagensis matagensiformisand Schedorhinotermes javanicus are the most successfully colonizedspecies, recorded almost in all the islands under reference.Besides the taxonomic treatment of the fauna, the paper also gives key to genera based on soldier caste

    Driven Intrinsic Localized Modes in a Coupled Pendulum Array

    Full text link
    Intrinsic localized modes (ILMs), also called discrete breathers, are directly generated via modulational instability in an array of coupled pendulums. These ILMs can be stabilized over a range of driver frequencies and amplitudes. They are characterized by a pi-phase difference between their center and wings. At higher driver frequencies, these ILMs are observed to disintegrate via a pulsating instability, and the mechanism of this breather instability is investigated.Comment: 5 pages, 6 figure

    A glance at imaging bladder cancer.

    Get PDF
    Purpose: Early and accurate diagnosis of Bladder cancer (BCa) will contribute extensively to the management of the disease. The purpose of this review was to briefly describe the conventional imaging methods and other novel imaging modalities used for early detection of BCa and outline their pros and cons. Methods: Literature search was performed on Pubmed, PMC, and Google scholar for the period of January 2014 to February 2018 and using such words as bladder cancer, bladder tumor, bladder cancer detection, diagnosis and imaging . Results: A total of 81 published papers were retrieved and are included in the review. For patients with hematuria and suspected of BCa, cystoscopy and CT are most commonly recommended. Ultrasonography, MRI, PET/CT using 18F-FDG or 11C-choline and recently PET/MRI using 18F-FDG also play a prominent role in detection of BCa. Conclusion: For initial diagnosis of BCa, cystoscopy is generally performed. However, cystoscopy can not accurately detect carcinoma insitu (CIS) and can not distinguish benign masses from malignant lesions. CT is used in two modes, CT and computed tomographic urography (CTU), both for dignosis and staging of BCa. However, they cannot differentiate T1 and T2 BCa. MRI is performed to diagnose invasive BCa and can differentiate muscle invasive bladder carcinoma (MIBC) from non-muscle invasive bladder carcinoma (NMIBC). However, CT and MRI have low sensitivity for nodal staging. For nodal staging PET/CT is preferred. PET/MRI provides better differentiation of normal and pathologic structures as compared with PET/CT. Nonetheless none of the approaches can address all issues related for the management of BCa. Novel imaging methods that target specific biomarkers, image BCa early and accurately, and stage the disease are warranted

    Exchange bias effect in the phase separated Nd_{1-x}Sr_{x}CoO_3 at the spontaneous ferromagnetic/ferrimagnetic interface

    Full text link
    We report the new results of exchange bias effect in Nd_{1-x}Sr_{x}CoO_3 for x = 0.20 and 0.40, where the exchange bias phenomenon is involved with the ferrimagnetic (FI) state in a spontaneously phase separated system. The zero-field cooled magnetization exhibits the FI (T_{FI}) and ferromagnetic (T_C) transitions at ~ 23 and \sim 70 K, respectively for x = 0.20. The negative horizontal and positive vertical shifts of the magnetic hysteresis loops are observed when the system is cooled through T_{FI} in presence of a positive static magnetic field. Training effect is observed for x = 0.20, which could be interpreted by a spin configurational relaxation model. The unidirectional shifts of the hysteresis loops as a function of temperature exhibit the absence of exchange bias above T_{FI} for x = 0.20. The analysis of the cooling field dependence of exchange bias field and magnetization indicates that the ferromagnetic (FM) clusters consist of single magnetic domain with average size around \sim 20 and ~ 40 \AA ~ for x = 0.20 and 0.40, respectively. The sizes of the FM clusters are close to the percolation threshold for x = 0.20, which grow and coalesce to form the bigger size for x = 0.40 resulting in a weak exchange bias effect.Comment: 9 pages, 9 figure

    Evaluation of a PACAP Peptide Analogue Labeled with (68)Ga Using Two Different Chelating Agents.

    Get PDF
    OBJECTIVE: The authors have conjugated chelating agents (DOTA and NODAGA) with a peptide (pituitary adenylate cyclase-activating peptide [PACAP] analogue) that has a high affinity for VPAC1 receptors expressed on cancer cells. To determine a suitable chelating agent for labeling with (68)Ga, they have compared the labeling kinetics and stability of these peptide conjugates. METHODS: For labeling, (68)GaCl3 was eluted in 0.1 M HCl from a [(68)Ge-(68)Ga] generator. The influences of peptide concentration, pH, and temperature on the radiolabeling efficiency were studied. The stability was evaluated in saline, human serum, DTPA, transferrin, and metallic ions (FeCl3, CaCl2, and ZnCl2). Cell binding assay was performed using human breast cancer cells (T47D). Tissue biodistribution was studied in normal athymic nude mice. RESULTS: Optimal radiolabeling (\u3e95.0%) of the DOTA-peptide conjugates required a higher (50°C-90°C) temperature and 10 minutes of incubation at pH 2-5. The NODAGA-peptide conjugate needed incubation only at 25°C for 10 minutes. Both radiocomplexes were stable in saline, serum, as well as against transchelation and transmetallation. Cell binding at 37°C for 15 minutes of incubation with (68)Ga-NODAGA-peptide was 34.0% compared to 24.5% for (68)Ga-DOTA-peptide. Tissue biodistribution at 1 hour postinjection of both (68)Ga-labeled peptide conjugates showed clearance through the kidneys. CONCLUSIONS: NODAGA-peptide showed more convenient radiolabeling features than that of DOTA-peptide

    Superconductivity in correlated disordered two-dimensional electron gas

    Full text link
    We calculate the dynamic effective electron-electron interaction potential for a low density disordered two-dimensional electron gas. The disordered response function is used to calculate the effective potential where the scattering rate is taken from typical mobilities from recent experiments. We investigate the development of an effective attractive pair potential for both disordered and disorder free systems with correlations determined from existing numerical simulation data. The effect of disorder and correlations on the superconducting critical temperature Tc is discussed.Comment: 4 pages, RevTeX + epsf, 4 figure

    Plasmon dispersion in quasi-one and one-dimensional systems with non-magnetic impurities

    Full text link
    We calculate the plasmon dispersion in quasi-one-dimensional quantum wires, in the presence of non-magnetic impurities, taking into consideration the memory function formalism and the role of the forward scattering. The plasma frequency is reduced by the presence of impurities. We also calculate, analytically, the plasmon dispersion in the Born approximation, for the scattering of the electrons by the non-magnetic impurities. We compare our result with the numerical results of Sarma and Hwang.Comment: 12 pages, no figures, Physica E, 40, 474, (2008

    Systematic study of proton-neutron pairing correlations in the nuclear shell model

    Full text link
    A shell-model study of proton-neutron pairing in 2p1f2p1f shell nuclei using a parametrized hamiltonian that includes deformation and spin-orbit effects as well as isoscalar and isovector pairing is reported. By working in a shell-model framework we are able to assess the role of the various modes of proton-neutron pairing in the presence of nuclear deformation without violating symmetries. Results are presented for 44^{44}Ti, 45^{45}Ti, 46^{46}Ti, 46^{46}V and 48^{48}Cr to assess how proton-neutron pair correlations emerge under different scenarios. We also study how the presence of a one-body spin-obit interaction affects the contribution of the various pairing modes.Comment: 12 pages, 16 figure
    • …
    corecore