Gold-coated iron nanoparticles (NPs) selectively and significantly (P <0.0001) inhibit proliferation of oral- and colorectal-cancer cells in vitro at doses as low as 5 mg/mL, but have little adverse effect on normal healthy control cells. The particle treatment caused delay in cell-cycle progression, especially in the S-phase. There was no significant difference in the NP uptake between cancer and control cells, and cytotoxicity resulted primarily from the iron core, before oxidation, rather than from the Fe ions released from the core. In contrast with magnetic NPs that usually serve as drug carriers, diagnostic probes or hyperthermia media, the iron, before oxidation, in the NPs selectively suppressed cancer cell growth and left healthy control cells unaffected in vitro and in vivo. This...
Diamagnetic samples placed in a strong magnetic field and a magnetic field gradient experience a magnetic force. Stable magnetic levitation occurs when the magnetic force exactly counter balances...Full Text Available
Lytic activity and recovery of natural killer (NK) cells was monitored in pediatric patients with leukemias (ALL, AML, CML, JMML) and myelodysplastic syndromes after transplantation of T cell depleted stem cells from matched unrelated (n = 18) and mismatched related (haploidentical, n = 29) donors. CD34 + selection with magnetic microbeads resulted in 8 x 10^3/kg residual T cells. No post-transplant immune suppression was given. NK cells recovered rapidly after transplantation (300 CD56+/@mL at day 30, median), whereas T cell recovery was delayed (median: 12 CD3+/@mL at day 90). NK activity was measured as specific lysis of K 562 targets several times (mean: 3 assays per patient). Four temporal patterns of lytic activity could be differentiated: consistently low, consistently high, decreas...
Naturally occurring and contaminant ferromagnetic and ferrimagnetic particles have been found within or near cells, and might allow pulsed magnetic fields to create transient cell membrane opening ("pores")....Full Text Available
The performance of a thermophotovoltaic (TPV) converter for solar energy is compared with that of direct solar energy conversion by silicon and germanium solar cells. The optical selectivity of an intermediate emitter is computed. Experimental results on selective emission, based on selectively emitting materials and on antireflection coatings on metals, are reported. For a TPV converter equipped with silicon solar cells, no selective emitter is found to yield better results than would be obtained by direct conversion. A TPV converter with germanium cells operating with a ThO/sub 2/-coated tungsten emitter, however, may achieve a conversion efficiency superior to that of direct solar energy conversion by either silicon or germanium solar cells.
We present results on searches for exotic particles (relativistic magnetic monopoles and WIMPs) and for UHE neutrinos, obtained with the Baikal neutrino telescope NT200.
Investigation of selective emitter solar cells has been undertaken using both device fabrication and accurate two-dimensional simulation program. Our results show that selective emitter solar cells exhibit a relatively low fill factor because of minority carriers crowding at the lateral junction. It is also found that carrier recombination in the space-charge region of the lateral junction limits open-circuit voltage improvements
The magnetic separation technology using sub-microsized ferromagnetic particle is indispensable in many areas of medical biosciences. For example, ferromagnetic particles (200-500 nm) are widely used for cell sorting in stem cell research with the use of cell surface-specific antigens. Nanosized ferromagnetic particles (10-20 nm) have been suggested as more suitable in drug delivery studies given their efficiency of tissue penetration, however, the magnetic separation method for them has not been established. One of the major reasons is that magnetic force acting on the object particles decreases drastically as a particle diameter becomes small. In this study, magnetic force acting on the targets was enhanced by the combination of superconducting magnet and the filter consisting of ferromagnetic particle. By doing so, we ...
This research deals with in the study of the use of innovating magnetic sensors in eddy current non destructive inspection. The author reports an analysis survey of magnetic sensor performances. This survey enables the selection of magnetic sensor technologies used in non destructive inspection. He presents the state-of-the-art of eddy current probes exploiting the qualities of innovating magnetic sensors, and describes the methods enabling the use of these magnetic sensors in non destructive testing. Two main applications of innovating magnetic sensors are identified: the detection of very small defects by means of magneto-resistive sensors, and the detection of deep defects by means of giant magneto-impedances. Based on the use of modelling, optimization, signal processing tools, probes are manufactured for these both applications.
The authors have performed a preliminary design for a persistent GHz NMR magnet at 23.5 T and 1.8 K operating conditions. In this paper the authors shall address the issues of realistic conductor selection, the coil design, the magnetic and mechanical analysis of the coil, and the required field uniformity. In addition, they shall describe the GHz magnet cryostat with a practical 1.8 K J-T refrigerator system. Finally vibration isolation system and field shield design and its associated field harmonics will be analyzed.
Substitution of various rare earths R within the class of R2PdSi3 single crystals with hexagonal AlB2-type crystallographic structure reveals the systematic dependence of anisotropic magnetic properties governed by the interplay of crystal-electric field effects and magnetic two-ion interactions. Here we compare the floating zone (FZ) crystal growth with radiation heating of compounds with R = Tb, Tm, Pr, and Gd. The congruent melting behavior enabled moderate growth velocities of 3 to 5 mmh-1. The preferred growth directions are close to the basal plane of the hexagonal unit cell. The composition of the crystals, except of Tb2PdSi3, is slightly Pd-depleted with respect to the nominal composition 16.7 at.% Pd. Thin precipitates of RSi secondary phases were detected in the crystal matrix. Their phase fraction can be diminished by growth from Pd-rich melt compositions and annealing treatments. The compounds exhibit ...
Selected derivatives of cyclophosphamide (CP) metabolites were synthesized and the solution chemistry of each was studied by "3"1P nuclear magnetic resonance (NMR) spectroscopy under a standard set of reaction conditions at physiological pH (7.4) and temperature (37"0C). Complementary "2H and "1"3C NMR spectral data was obtained using isotopically ("2G and "1"3C) enriched CP metabolites. The CP derivatives were synthesized by the ozonolysis of substituted 3-butenyl phosphorodiamidates, and were isolated as analogues of either cis and trans 4-hydroperoxy-CP or aldophosphamide (AP). The relative ratios of the tautomeric species, 4-hydroxy-CP and AP, and their half-lives (T/sub 1/2/) were measured by "3"1P NMR spectroscopy. The influence of CP metabolites on perfused U-937 cells, a CP-sensitive human lymphoma, was observed by high resolution "3"1P NMR spectroscopy. In this manner, it was possible to measure, for the first ...
Epidemiologic studies suggest a weak link between occupational or residential exposure to extremely low frequency electromagnetic fields and cancer, especially tumors of the central nervous and hematopoietic systems. This report discusses these studies with reference to basic research on ELF EMF bioeffects relevant to cancer-promoting mechanisms. Many of the studies suggest a possible interaction of ELF EMF with the immune system, endocrine system, or growth-regulatory signals and morphogenic movements that involve calcium flux through cell membranes. Many bioeffects have been reported only with certain specific combinations of frequency, amplitude, and orientation of the EMF signal with respect to the geomagnetic field. The possibility of signal-specific effects raises a complication in dosimetry for both epidemiologic and experimental studies since ELF EMF effects may not be directly related to field strength. The report concludes with a discussion of design ...
Three different magnetic regimes; aerial, surface and buried; each with three different forces, have been used to investigate their effects on the water contents and photosynthetic pigments of sweet basil plants (Ocimum basilicum L.). Two groups of sweet basil seeds, Ocimum basilicum L. have been cultivated, one under normal conditions and the second has been subdivided into three portion (aerial, surface and buried) to examine the effect of different magnetic forces coming from the three directions on the resulted plants. At all directions of magnets, water contents have been significantly affected by the magnetic forces. Chlorophyll A and carotene contents have been affected, as well, according to the three magnetic forces coming from soil surface regime only. Chlorophyll B did not significantly affected by differences magnetic forces in the three regimes, but ...
Synthetic polymers and nanomaterials display selective phenotypic effects in cells and in the body that affect signal transduction mechanisms involved in inflammation, differentiation, proliferation,...Full Text Available
Select members of the Reoviridae are the only nonenveloped viruses known to induce syncytium formation. The fusogenic orthoreoviruses accomplish cell-cell fusion through a distinct...Full Text Available
Taste cells use multiple signaling mechanisms to generate appropriate cellular responses to discrete taste stimuli. Some taste stimuli activate G protein coupled receptors (GPCRs) that cause calcium...Full Text Available
Pancreatic islet transplantation into the liver provides a possibility to treat selected patients with brittle type 1 diabetes mellitus. However, massive early β-cell death increases the number...Full Text Available
Bacterial pathogens use virulence strategies to invade epithelial barriers, but active processes of epithelial cells may also contribute to the endocytosis of microbial particles. To focus on the latter,...Full Text Available
BackgroundMalaria resistance by the sickle cell trait (genotype HbAS) has served as the prime example of genetic selection for over half a century. Nevertheless, the mechanism...Full Text Available
I present results for the mass spectrum of excited baryons and pentaquarks using overlap fermions and Bayesian curve-fitting method; and magnetic moments and polarizabilities for a variety of hadrons in the background field method.
I present results for the mass spectrum of excited baryons and pentaquarks using overlap fermions and Bayesian curve-fitting method; and magnetic moments and polarizabilities for a variety of hadrons in the background field method.
Scientists at JPL have developed chemical and biological techniques using microspheres filled with drugs, electron-opaque metals, or radioactive, fluorescent, magnetic or electrically charged materials to label specific groups of cells. Synthetic polymeric microspheres are coupled with specific antibodies to form reagents called immunomicrospheres, which can seek out and attach themselves to any specific group of cells. These cell-labeling techniques, therefore, open new avenues not only to the basic study of cells but also to the diagnosis and treatment of many diseases, including cancer.
A design of the modular coil system for CHS-qa has been made for the plasma configuration '2b32' with the aspect ratio 3.2. The magnetic field strength and the major radius are 1.5 T and 1.5 m, respectively. The normal component of magnetic field produced by the modular coils is minimized on the plasma boundary to obtain the optimum coil design. We put engineering constraint on the distance between adjacent modular coils and the radius of coil curvature. The dependence of the residual normal component of the field on these conditions is examined, and the realistic values for them are selected. Additional coils to control various properties of the magnetic field configuration (the rotational transform, the magnetic well depth, etc.) have been designed and a flexibility of the magnetic field configuration is realized. For the case that the ...
The macroscopic behavior of magnetostrictive materials results from domain evolutions occurring at a microscopic scale. The author shows how to compute magnetization and magnetostriction curves by appraising the behavior of the underlying microstructures. The method hinges on an averaging device (Young measures), which allows one to pass from the microscopic to the macroscopic scale. He takes into account the kinematical constraints on the accommodation of elastic effects, and he highlights the role of material symmetry in the selection of energetically optimal microstructures.
CERN has encouraged the US-LARP collaboration to participate in Phase I of the LHC luminosity upgrade by analyzing the benefits gained by using Nb3Sn technology to replace the functionality of select NbTi magnets that CERN is committed to construct. Early studies have shown that the much higher gradients (shorter magnetic lengths) and temperature margins (quench stability) of Nb3Sn magnets compared to their NbTi counterparts is favorable--allowing the insertion of additional absorbers between Q1 and Q2, for example. This paper discusses the relative merits of the NbTi and Nb3Sn options.
MAGNETIC FORMING .............. MAGNETIC INDUCTION ............ MAGNETIC MATERIALS ............ MAGNETIC MEASUREMENT .......... MAGNETIC PERMEABILITY . ...
The mapping of the magnetic flux bundle from the center cell to the Plasma Potential Control plates (PPC) on the end fan of the Tandem Mirror Experiment Upgrade (TMX-U), was improved by the addition of trim coils (12,000 amp-turns) on each side of each end fan next to the pump beam magnetic shields. The coils' axes are oriented perpendicular to the machine centerline. These coils made the necessary corrections to the field-line mapping, while keeping the field in the nearby pump beam magnetic shield below the saturation threshold. This paper briefly describes the problem, discusses the design as it evolved, and presents the results of the field testing. A brief description of the improvement in the machine performance is also included.
In this review, we show how advances in the theory of magnetic pseudodifferential operators (magnetic $\\Psi$DO) can be put to good use in space-adiabatic perturbation theory (SAPT). As a particular example, we extend results of [PST03] to a more general class of magnetic fields: we consider a single particle moving in a periodic potential which is subjectd to a weak and slowly-varying electromagnetic field. In addition to the semiclassical parameter $\\eps \\ll 1$ which quantifies the separation of spatial scales, we explore the influence of additional parameters that allow us to selectively switch off the magnetic field. We find that even in the case of magnetic fields with components in $C_b^{\\infty}(\\R^d)$, e. g. for constant magnetic fields, the results of Panati, Spohn and Teufel hold, i.e. to each isolated family of Bloch bands, ...
Some laboratory experiments have suggested that power-frequency electric and magnetic fields (EMF) may be capable of influencing calcium efflux from cell membranes, pineal function, and circadian rhythms....Full Text Available
Iron is a central element in the metabolism of normal and malignant cells. Abnormalities in iron and ferritin expression have been observed in many types of cancer. Interest in characterizing iron compounds...Full Text Available
BackgroundStable transgenesis is an undeniable key to understanding any genetic system. Retrovirus-based insertional strategies, which feature several technical challenges when they...Full Text Available
This document summarizes work done at the Astronautics Technology Center of the Astronautics Corporation of America (ACA) in Phase 1 of a four phase program leading to the development of a magnetic liquefier for hydrogen. The project involves the design, fabrication, installation, and operation of a hydrogen liquefier providing significantly reduced capital and operating costs, compared to present liquefiers. To achieve this goal, magnetic refrigeration, a recently developed, highly efficient refrigeration technology, will be used for the liquefaction process. Phase 1 project tasks included liquefier conceptual design and analysis, preliminary design of promising configurations, design selection, and detailed design of the selected design. Fabrication drawings and vendor specifications for the selected design were completed during detailed design. The design of a subscale, ...
This letter describes a new simple fabrication process, developed recently for blue response'' improvement in low-cost polycrystalline silicon solar cells. A selective emitter is created by heavily doping the emitter, followed by a wet etching-back of the cell area between the fingers. An improvement up to 17 mV in {ital V}{sub oc}, 1.5 mA/cm{sup 2} in {ital J}{sub sc}, and 1% (absolute value) in {eta} is obtained. Effective phosphorus gettering, self-alignment, and application in a low-cost full screenprinting technology are the main advantages of the proposed process.
The synthesis of a new kind of magnetic, fluorescent multifunctional nanoparticles (~30 nm in diameter) was demonstrated, where multiple fluorescent CdTe quantum dots (QDs) are covalently linked...Full Text Available
Abstract. Objective: Lapatinib (Tykerb, GW572016), a potent inhibitor of the catalytic activities of epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER2) (ErbB2), inhibits population growth of selected EGFR and HER2 overexpressing cell lines. Previous studies with a small number of cell lines suggest a correlation between overexpression of EGFR and/or HER2 and sensitivity to growth inhibition by lapatinib; however, the precise determinants of lapatinib selectivity for tumour and/or other cells remain unclear. Materials and methods: To clarify the determinants of its selectivity in cultured cells, lapatinib-induced cell population growth inhibition and relative EGFR and HER2 protein expression were quantified in 61 different human tumour cell lines fro...
Chronic HTLV-I (human T cell lymphotropic virus type I) infection may cause adult T cell leukemia/lymphoma (ATL), a disease with dismal long-term prognosis. The HTLV-I transactivator, Tax, initiates...Full Text Available
Cyclooxygenase-2 (COX-2) content is increased in many types of tumor cells. We have investigated the mechanism by which resveratrol, a stilbene that is pro-apoptotic in many tumor cell lines, causes apoptosis in human head and neck squamous cell carcinoma UMSCC-22B cells by a mechanism involving cellular COX-2. UMSCC-22B cells treated with resveratrol for 24 h, with or without selected inhibitors, were examined: (1) for the presence of nuclear activated ERK1/2, p53 and COX-2, (2) for evidence of apoptosis, and (3) by chromatin immunoprecipitation to demonstrate p53 binding to the p21 promoter. Stilbene-induced apoptosis was concentration-dependent, and associated with ERK1/2 activation, serine-15 p53 phosphorylation and nuclear accumulation of these proteins. These effects were blocked by ...
Ex vivo expanded peripheral blood progenitor cells (PBPC) have been shown to provide rapid neutrophil engraftment, and in some patients, to eliminate neutropenia after transplantation to support high-dose chemotherapy. However, the effect of expansion culture on stem cell content and potential loss of stem cells caused by induction of differentiation remains a concern. We have transplanted 21 patients with breast cancer with expanded autologous PBPC, with 11 patients receiving expanded PBPC as their sole hematopoietic cell source. In these studies, the CD34+ cells were selected and cultured for 10 days in defined media containing 100 ng/mL each of recombinant human stem cell factor (rhSCF), recombinant human granulocyte colony stimulating factor (rhG-CSF), and recombinant human megakaryocy...
We present an x-ray magnetic circular dichroism (XMCD) study performed on both Ho{sub 6}Fe{sub 23} and Y{sub 6}Fe{sub 23} compounds as a function of the temperature. The combined analysis of both Fe K-edge and Ho L{sub 2,3}-edge XMCD spectra recorded through the magnetic compensation transition allows us to disentangle the thermal dependence of both Fe and Ho magnetic moments in Ho{sub 6}Fe{sub 23}. In addition, contributions from Ho ions to the Fe K-edge XMCD signals and, conversely, from Fe ions to the Ho L{sub 2,3}-edge XMCD spectra have been clearly identified. These extra contributions, arising from the strong Fe(3d)-Ho(5d) hybridization, have been isolated from the spectra and correlated with the magnetic state of both Ho and Fe ions surrounding the absorbing site. The influence of these contributions to the values of the orbital and spin moments derived by using sum rule analysis is also shown.
Electromagnetic fields have been reported to cause a variety of biological effects. It has been hypothesized that many of these phenomena are mediated by a primary effect on the concentration of cytosolic free calcium ((Ca2+)i). We investigated the effects of exposure to electromagnetic fields on (Ca2+)i in HL-60 cells using the Ca2(+)-sensitive fluorescent indicator indo-1. Indo-1-loaded cell samples were exposed to a radiofrequency electromagnetic field, a static magnetic field, and a time-varying magnetic field, which were generated by a magnetic resonance imaging (MRI) unit. We found that a 23-min exposure to all three fields, in combination, induced a significant increase in (Ca2+)i of 31 +/- 8 (SE) nM (P less than 0.01, n = 13) from a basal level of 121 +/- 8 nM. Also, cells exposed to only the time-varying magnetic field had a mean ...
The magnetic pyrochlore Er{sub 2}Ru{sub 2}O{sub 7} has been studied with neutron scattering and susceptibility measurements down to a base temperature of 270 mK. For the low temperature phase in which the Er sublattice orders, new magnetic Bragg peaks are reported which can be indexed with integer (hkl) for a face centered cubic cell. Inelastic measurements reveal a wealth of crystal field levels of the Er ion and a copious amount of magnetic scattering below 15 meV. The three lowest groups of crystal field levels are at 6.7, 9.1 and 18.5 meV.
Magnetic properties of the Al1-xGaxFeO3 family of oxides crystallizing in a non-centrosymmetric space group have been investigated in detail along with structural aspects by employing X-ray and neutron diffraction, Moessbauer spectroscopy and other techniques. The study has revealed the occurrence of several interesting features related to unit cell parameters, site disorder and ionic size. Using first-principles density functional theory based calculations, we have attempted to understand how magnetic ordering and related properties in these oxides depend sensitively on disorder at the cation site. The origin and tendency of cations to disorder and the associated properties are traced to the local structure and ionic sizes. -- Graphical abstract: We have studied both experimentally and theoretically the important role of disorder at the cation site on magnetic and related properties of the Al1-xGaxFeO3 ...
31P nuclear magnetic resonance (NMR) spectroscopy was used to monitor the response of oil palm (Elaeis guineensis) and carrot (Daucus carota) cell suspensions...Full Text Available
A rechargeable cell is disclosed which is characterized in the following manner. A positive electrode is formed from a manganese oxide electrode material. This manganese oxide electrode material contains a heavy metal selected from the group comprising lead, bismuth, and mixtures of lead and bismuth. The cell also contains a negative electrode of zinc. A separator is provided between the positive electrode and the negative electrode. An alkaline electrolyte consisting essentially of an alcohol and an alkaline hydroxide is also contained in the rechargeable cell in contact with both the positive electrode and the negative electrode.
Transdifferentiation of an individual's own cells into functional differentiated cells to replace an organ's lost function would be a personalized approach to therapeutics. In this two part series, we will describe the progress toward establishing functional transdifferentiated adrenal cortical cells. In this article (Part 1), we describe adrenal development and function, and discuss genes involved in these processess and selected for use in our pilot studies of transdifferentiation that are presented in the second article (Part 2).
The use of magnetic resonance imaging for diagnosis and the preoperative staging of renal cell carconoma was evaluated in 79 patients with 88 tumors. Gradient-echo and spin-echo images before and after intravenous administration of Gadolinium DTPA were compared with the results of computed tomography (CT) and histologic staging. The two imaging techniques had comparable results: T-stage was predicted correctly with CT in 78%.4% and with MRI in 84.0% of the cases, while the N-stage was accurately assessed in 81.8% and 79.5%, respectively. MRI had some advantages in diagnosing perirental tumor spread and in excluding an infiltration beyond Gerota's fascia. Therefore, MRI is a true alternative to CT for staging large renal cell carcinomas and especially for patients with contraindications for iodinated contrast agents. (orig.).
Direct current motors are used in photovoltaic systems. Important characteristics of electric motors are the starting to rated current and the torque ratios. These ratios are dictated by the size of the solar cell array and are different for the various dc motor types. The paper deals with the calculation of the starting to rated current ratio and starting to rated torque ratio of the permanent magnet, separately, series and shunt excited motors when powered by solar cells for the two cases: where (1) the system includes a maximum-power-point-tracker (MPPT) and (2) without an MPPT. Comparing these two cases, one gets a torque magnification of about 3 for the permanent magnet motor and about 7 for other motor types at rated design insolation. The calculation of the torques may assist the PV system designer to determine the advantage of including an MPPT in the system as far as the starting ...
The current role of magnetic resonance imaging (MRI) in different organ systems is discussed and compared to nuclear medicine and to other available clinical diagnostic modalities. The value of optimizing radiofrequency pulse sequence selection to provide additional tissue characterization is also described. The results of nuclear medicine and MRI studies in 56 patients are compared to evaluate the clinical diagnostic contribution of each imaging modality for various pathological processes. In addition, the state-of-the-art MRI systems and future development in MRI technology with its potential contribution is defined.
Reference is made to Cheng and Leblond (Amer. J. Anat.; 141:537 (1974)) who used tritiated thymidine to kill cells synthesising DNA in the crypts of the small intestine. Amongst their findings was that very low doses caused measurable cell killing and that the killing was not random throughout the crypt but occurred selectively at the crypt base where stem cells are presumably located. It is here reported that the presence of hypersensitive cells at the base of the crypts can be demonstrated after whole-body X- or gamma-irradiation, and the time sequence for the production and loss of the killed cells is described together with their dose-response relationship. The studies were conducted on mice. The data were expressed as surviving rather than killed cells, and it was established that the crypt are amongst the most sensitive of mammalian ...
A brief overview if provided of selected reports presented at the International Symposium on Molecular Mechanisms of Radiation- and Chemical Carcinogen-Induced Cell Transformation held at Mackinac Island, Michigan on September 19-23, 1993.
Hypoxia inducible factor-1 (HIF-1) promotes tumor cell adaptation to microenvironmental stress. HIF-1 is up-regulated in irradiated tumors and serves as a promising target for radiosensitization....Full Text Available
There is a quest for the development of a new generation of vaccines consisting of well-defined subunit antigens. For a number of practical reasons it is attractive to develop vaccines on the basis...Full Text Available
The goal of ultrasonic molecular imaging is the detection of targeted contrast agents bound to receptors on endothelial cells. We propose imaging methods that can distinguish adherent microbubbles...Full Text Available
By pretreating simian virus 40-infected BSC-1 cells with glucosamine, [3H]uridine labeling of both cellular and viral RNA can be halted instantaneously by addition of cold uridine. We have...Full Text Available
The pathogenesis of Pseudomonas aeruginosa disseminated infections depends on bacterial interaction with blood vessels. We have hypothesized that in order to traverse the endothelial barrier, bacteria...Full Text Available
The ability to achieve tumor selective expression of therapeutic genes is an area that needs improvement for cancer gene therapy to be successful. One approach to address this is through the...Full Text Available
BackgroundCD26 (dipeptidyl peptidase IV, DPPIV) is a 110 kDa surface glycoprotein expressed in most normal tissues, and is a potential novel therapeutic target for selected cancers....Full Text Available
The nicotinic acetylcholine receptor (AChR) controls signal transmission between cells in the nervous system. Abused drugs such as cocaine inhibit this receptor. Transient kinetic investigations indicate...Full Text Available
Cd36 is a small-molecular-weight integral membrane protein expressed in a diverse, but select, range of cell types. It has an equally diverse range of ligands and physiological functions, which has...Full Text Available
Transgenic mouse models have contributed considerably to our understanding of the cellular and molecular mechanisms by which androgens control spermatogenesis. Cell-selective ablation of the androgen...Full Text Available
The thermophotovoltaic (TPV) option was not selected for further deep space mission technology development in NASA for several reasons. Chief among them was the large radiator required to keep the photovoltaic cells at a sufficiently low operating temperature. This led to significant integration problems with the spacecraft and limited sensor view angles. It is clear that the issue of cell temperature is crucial for space applications because of radiator size and system impact. Many efforts have focused on matching cell band gap to appropriate emitters in the 1 to 2 {mu}m range, resulting in band gaps in the 0.5 to 0.8 eV range. However, low band gaps lead to low open circuit voltages ({approximately}0.25 to 0.45 V) caused by high intrinsic carrier concentrations (n{sub i}{sup 2}). Thus, in order to obtain high performance. Photovoltaic cell temperatures must be kept near room ...
The 12 GeV upgrade at Jefferson Lab has identified two new large spectrometers as Physics detectors for the project. The first is a 7.5 Gev/c 35 m-sr. spectrometer that requires a pair of identical Combined Function Superconducting Magnets (CFSM) that can simultaneously produce 1.5 T dipole fields and 4.5 T/m quadrupole fields inside a warm bore of 120cm. The second is an 11 GeV/c 2 m-sr. spectrometer that requires a CFSM that simultaneously produces a dipole field of 4.0 T and a quadruple field of 3.0 T/m in a 60 cm warm bore. Magnetic designs using TOSCA 3D have been performed to realize the magnetic requirements, provide 3d fields for optics analysis and produce field and force information for the engineering feasibility of the magnets. A two-sector cos( theta )/cos(2 theta ) design with a low nominal current density, warm bore and warm iron design has been selected and analyzed. ...
Certain transition metal chalcogenides are promising materials for use as cathodes in nonaqueous lithium batteries involving the intercalation into these layered compounds. The electrochemical behavior of the chalcogenides depends on various properties such as structure, stoichiometry, electrical conductivity, crystal morphology, etc. The influence of these properties and of the ultimate practical application of the battery on the selection of cathode material is discussed. Battery performance of selected cathode materials is discussed and life limitations due to the limited cycle life of lithium anodes are outlined. 15 refs.
We propose a novel method for ultrasensitive isotope analysis that combines magnetic mass selection, resonant charge-exchange neutralization, and resonant laser ionizaion. Our method attains high isotopic abundance selectivity by means of continuous multistage separation of ions stored in a small ring. For the environmentally interesting case of /sup 90/Sr versus /sup 88/Sr we estimate that sensitivity better than 10/sup -15/ for a throughput of 10/sup 13/ atoms/sec and an efficiency (after the ion source) greater than 10% are readily achievable.
The use of a selective epitaxial growth technique for fabricating YBCO thin-film microstructures is described. No film post-deposition processing is required; hence damage to the structure is minimized. The technique is compatible with a passivation process to protect the structure without exposure to air. The microbridges, Josephson junctions and rf SQUIDs protected by an amorphous YBCO passivation have long lifetime even after severe accelerated aging tests. Rf SQUIDs fabricated by this technique show a significant reduction of low-frequency noise when operating in weak magnetic fields compared with SQUIDs fabricated by the conventional ion beam etching technique. (author)
In order to understand the physical processes concerned with the selective heating by ion cyclotron resonance and with the subsequent collection of heated particles, experiments were carried out with the extraction of lithium samples, enriched with "6Li isotopes. Probe and integral extractors allow to collect enriched Li at the end of the selective heating region. Surface density distribution on the collector and local isotopic content of lithium are measured, as a function of the screen height and the retarding potential. Dependence of the collected amount of lithium and of its isotopic content on the value of the magnetic field is also measured. 4 figs., 2 tabs., 5 refs.
Current multi-scale computational models of ventricular electromechanics describe the full process of cardiac contraction on both the micro- and macro- scales including: the depolarization of cardiac cells, the release of calcium from intracellular stores, tension generation by cardiac myofilaments, and mechanical contraction of the whole heart. Such models are used to reveal basic mechanisms of cardiac contraction as well as the mechanisms of cardiac dysfunction in disease conditions. In this paper, we present a methodology to construct finite element electromechanical models of ventricular contraction with anatomically accurate ventricular geometry based on magnetic resonance and diffusion tensor magnetic resonance imaging of the heart. The electromechanical model couples detailed repres...
Inhibition of large conductance calcium-activated potassium (BKCa) channels mediates, in part, oxygen sensing by carotid body type I cells. However, BKCa channels remain active...Full Text Available
BackgroundHIV infection causes a qualitative and quantitative loss of CD4+ T cell immunity. The institution of anti-retroviral therapy (ART) restores CD4+ T...Full Text Available
Propagation of an intense charged particle beam pulse through a background plasma is a common problem in astrophysics and plasma applications. The plasma can effectively neutralize the charge and current of the beam pulse, and thus provides a convenient medium for beam transport. The application of a small solenoidal magnetic field can drastically change the self-magnetic and self- electric fields of the beam pulse, thus allowing effective control of the beam transport through the background plasma. An analytic model is developed to describe the self-magnetic field of a finite- length ion beam pulse propagating in a cold background plasma in a solenoidal magnetic field. The analytic studies show that the solenoidal magnetic field starts to infuence the self-electric and self-magnetic fields when ?ce > ?pe?b, where ?ce = e?/mec is the electron gyrofrequency, ...
Thermophotovoltaic (TPV) converters were developed and tested at the heat source operating temperature of 1,700 K. Rare-earth-doped yttrium aluminum garnet (YAG) and lutetium yttrium aluminum garnet (Lu, YAG) selective emitters, as well as a blackbody emitter, were coupled to InGaAs/InP photovoltaic (PV) cells and bandpass/infrared (IR) reflector filters. YAG-based selective emitters were adopted with Ho, Tm, and Er. PV cells had bandgaps of 0.51, 0.57, and 0.69 eV. Converter energy conversion efficiencies approaching 30%, as well as electrical output power densities near 2 W/cm{sup 2} were demonstrated. The overall performance of the filtered blackbody-based converter was found to be superior to the selective emitter YAG-based converters. The details of the measurements performed on the above converters and their individual components are presented.
Thermophotovoltaic energy conversion achieves direct conversion of thermal energy to electricity without the need for complex dynamic machinery operating in one of several possible thermodynamic cycles. This paper presents an analysis of a hybrid solar thermophotovoltaic (STPV) energy conversion system in which a receiver/photovoltaic (PV) array subsystem is powered by either a solar concentrator or a fossil fuel combustion source. The overall TPV system efficiency is calculated using an appropriate selective emitter and a spectrally tuned solar cell designed to achieve maximum conversion efficiency in the narrow band emitted by the selective emitter. Two limiting cases are examined to place upper and lower bounds on system performance. The estimates of system performance are based on actual experimental data from PV cells and selective emitters.
Abstract MicroRNAs (miRNAs) play important roles in global gene regulation. Researchers in recombinant protein production have proposed miRNAs as biomarkers and cell engineering targets. However, miRNA expression remains understudied in Chinese Hamster Ovary cells, one of the most commonly used host cell systems for therapeutic protein production. To profile highly conserved miRNA expression, we used the miRCURY- miRNA array for screening miRNAs in CHO cells. The selection criteria for further miRNA profiling included positive hybridization signals and experimentally validated predicted regulatory targets. On the basis of screening, we selected 16 miRNAs for quantitative RT-PCR profiling. We profiled miR expression in parental CHO DG44 and CHO K1 cell lines as well as four recombinant DG44...
The static magnetization of solid "3He contained in sintered copper was measured. The results of the density on the melting curve show that below 5 mK, the magnetization M rises above the Curie-Weiss law extrapolated from high temperature. It reaches a maximum of twice as much as the Curie Weiss law value at temperature Tm, which would be somewhat below 1.25 mK if the system could be warmed up at infinitesimally slow rate. Below Tm, M decreases rapidly to 0.4 of its maximum, then appears to become independent of temperature. The previously reported decrease of specific heat below the Curie-Weiss law value in the range below 4 mK is apparently related to the increase of M in that range. At the low temperature end, apparent decrease of M is due to the fact that there is background magnetization which is out of equilibrium with the thermometer when there is solid "3He in the sample cell. It is suspected ...
In this paper, we discuss various aspects of the development of an inverted-grown AlGaAs/GaAs cascade solar cell incorporating a patterned germanium tunnel junction. Topics include the development of the Al{sub 0.37}Ga{sub 0.63}As top cell, the growth of the GaAs bottom cell over the patterned germanium tunnel junction, and a technique for selective removal of thin AlGaAs/GaAs heterostructures after lattice-matched growth on germanium substrates. The problems to be overcome for the achievement of around 30% efficiencies in the AlGaAs/GaAs cascade cell under concentrator applications are also discussed. (orig.).
Three classes of solar emanations, namely, photon radiation from solar flares, solar energetic particles, and inhomogeneities in the solar wind that drive magnetic storms, are examined, and their effects on humans and technological systems are discussed. Solar flares may disrupt radio communications in the HF and VLF ranges. Energetic particles pose a special hazard at low-earth orbit and above, where they can penetrate barriers such as spacesuits and aluminum and destroy cells and solid state electronics. Energetic solar particles also influence terrestrial radio waves propagating through polar regions. Magnetic storms may disturb the operation of navigation instruments, power lines and pipelines, and satellites; they give rise to ionospheric storms which affect radio communication at all latitudes. There is also a growing body of evidence that changes in the geomagnetic field affect biological systems. 3 refs.
In vitro cytocompatibility and cellular interactions of lauric acid and dextran-coated magnetite nanoparticles were evaluated with two different cell lines (mouse fibroblast and human cervical carcinoma). Lauric acid-coated magnetite nanoparticles were less cytocompatible than dextran-coated magnetite nanoparticles and cellular uptake of lauric acid-coated magnetic nanoparticles was more than that of dextran-coated magnetite nanoparticles. Lesser cytocompatibility and higher uptake of lauric acid-coated magnetite nanoparticles as compared to dextran-coated magnetic nanoparticles may be due to different cellular interactions by coating material. Thus, coating plays an important role in modulation of biocompatibility and cellular interaction of magnetic nanoparticles.
In vitro cytocompatibility and cellular interactions of lauric acid and dextran-coated magnetite nanoparticles were evaluated with two different cell lines (mouse fibroblast and human cervical carcinoma). Lauric acid-coated magnetite nanoparticles were less cytocompatible than dextran-coated magnetite nanoparticles and cellular uptake of lauric acid-coated magnetic nanoparticles was more than that of dextran-coated magnetite nanoparticles. Lesser cytocompatibility and higher uptake of lauric acid-coated magnetite nanoparticles as compared to dextran-coated magnetic nanoparticles may be due to different cellular interactions by coating material. Thus, coating plays an important role in modulation of biocompatibility and cellular interaction of magnetic nanoparticles.
Studies have shown that CCl_4 administration to rats inhibits endoplasmic reticulum calcium pump activity and reduces the amount of calcium associated with subsequently isolated microsomal subcellular fractions. This report confirms that exposure of isolated hepatocytes to CCl_4 rapidly produces these effects in isolated parenchymal cells and demonstrates that when isolated hepacytes are exposed to CCl_4 calcium is rapidly released from cells. This release can be detected with a calcium ion-selective electrode when cells are incubated in a medium with low extracellular calcium. Calcium released from an intracellular pool(s) may initiate hepatotoxic changes in liver. (author).
The first essential before embarking on the radiation-hardening of electrical insulation - mostly magnet coils - in any beam line application is to obtain a reliable estimate of the dose to the components. These are examples ( switchyards at SLAC and LAMPF) where the degree of hardness specified was much higher than was required. Although experience shows that the cost premium for substantial radiation - hardening is of the order of 10%, it has also become clear that well - designed beam line have negligible losses: hardening is required only in the vicinity of targets, collimators or other beam - intercepting devices. Where the beam is deliberately scraped, local shielding will minimize the associated radiation in the surroundings. Electron machines have their own special problems due to synchrotron radiation, so certainly coils and other electrical equipment should be kept away from the beam bend - plane. Because proton beams interact with thick targets in the ...
Abstract A fabrication process for Emitter-Wrap-Through solar cells on monocrystalline material with high quality gap passivation by wet thermal silicon dioxide is investigated. Masking and structuring steps are performed by screen-printing technology. Via-holes are created by an industrially applicable high-speed laser drilling process. The cell structure features a selective emitter structure fabricated in a single high temperature step: a highly doped emitter at the via-holes and the rear side, allowing for a low via-hole resistivity as well as a low resistivity contact to screen-printed pastes, and a moderately doped front side emitter exhibiting high quantum efficiency in the low wavelength range. Therefore a novel approach is applied depositing either doped or undoped PECVD silicon d...
Invading melanoma spreads to local and unpredictable distant location at the early stages of its development. It is justifiable, therefore, to classify the disease as a systemic disorder. This requires a systemic treatment that reaches all melanoma cells irrespective of whether they are singly dispersed and in circulation or already forming solid tumours of various sizes. Targeted radiotherapy affects directly and selectively cancer cells provided an appropriate radionuclide and its carrier are chosen. Melanoma is a pigmented tumour. Methylene blue (MTB)) accumulates selectively in melanoma cells due to its exceptionally high affinity to melanin. MTB serves, therefore, as a carrier for radionuclides. "2"1"1At-MTB has proved to be particularly effective in treating disseminated melanoma when administered systemically and, at the same time, non-toxic to normal non-pigmented and ...
Palladium/magnetite nanoparticulate catalysts were developed for efficient elimination of halogenated organic pollutants from contaminated wastewater. Particle recovery from treated water can be ensured via magnetic separation. However, in worst-case scenarios, this catalyst removal step might fail, leading to particle release into the environment. Therefore, a toxicological study was conducted to investigate the impact of both pure magnetite and palladium/magnetite nanoparticle exposure upon human skin (HaCaT) and human colon (CaCo-2) cell lines and a cell line from rainbow trout gills (RTgill-W1). To quantify cell viability after particle exposure, three endpoints were examined for all tested cell lines. Additionally, the formation of reactive oxygen species was studied for the human cells. The results showed only minor effects of the particles on the tested ...
We introduce a methodology for analysis of multiwavelength data from X-ray selected BL Lac (XBL) objects detected in the TeV regime. By assuming that the radio--through--X-ray flux from XBLs is nonthermal synchrotron radiation emitted by isotropically-distributed electrons in the randomly oriented magnetic field of a relativistic blazar jet, we obtain the electron spectrum. This spectrum is then used to deduce the synchrotron self-Compton (SSC) spectrum as a function of the Doppler factor, magnetic field, and variability timescale. The variability timescale is used to infer the comoving blob radius from light travel-time arguments, leaving only two parameters. With this approach, we accurately simulate the synchrotron and SSC spectrum of flaring XBLs in the Thomson through Klein-Nishina regimes. Photoabsorption by interactions with internal jet radiation and the intergalactic background light (IBL) is included. Doppler ...
This study is devoted to the formation of high-low-level-doped selective emitter for crystalline silicon solar cells for photovoltaic application. We report here the formation of porous silicon under chemical reaction condition. The chemical mixture containing hydrofluoric and nitric acid, with de-ionized water, was used to make porous on the half of the silicon surface of size 125 x 125 cm. Porous and non-porous areas each share half of the whole silicon surface. H{sub 3}PO{sub 4}:methanol gives the best deposited layer with acceptable adherence and uniformity on the non-porous and porous areas of the silicon surface to get high- and low-level-doped regions. The volume concentration of H{sub 3}PO{sub 4} does not exceed 10% of the total volume emulsion. Phosphoric acid was used as an n-type doping source to make emitter for silicon solar cells. The measured emitter sheet resistances at the high- and low-level-doped regions ...
This report summarizes the results and activities funded by this three-year award. The principal goal of this project was to determine the thermal conductivity in clusters of galaxies. Intracluster plasmas possess chaotic magnetic fields. Since charged particles are constrained to move primarily along magnetic field lines, the topology of intracluster magnetic fields slows particle diffusion relative to the non-magnetized case, thereby reducing the thermal conductivity. Our first approach to this problem was to employ the static-magnetic-field approximation. In reality, intracluster magnetic field lines are constantly moving, since they are advected by turbulent intracluster motions. The turbulent velocities, however, are much smaller than the rapid speeds of thermal electrons, which make the dominant contribution to the thermal conductivity. In the static-field ...
In this experiments, we established long-termed culture methods of bone marrow stromal cells for proliferation and differentiation of stem cells. And we selected some extracts which support maximal proliferation of stromal cells with this method. We conformed the synergic effects of herbal mixture extracts for stromal cell growth. The proliferation of stromal cells was increased rather by the addition of mixture extracts than by addition of single strain extract. In the previous and cooperative experiments, we selected complex extracts (Him-I, Him-II) which increased the number of nonadherent mononuclear cells. Different cytokine expression patterns were observed stromal cells cultured in the presence or absence of mixture extracts which support differentiation of nonadherent ...
The authors describe the application of an approximate fuzzy C-means (AFCM) clustering algorithm as a data dimension reduction approach to medical magnetic resonance images (MRI). Image data consisted of one T1-weighted, two T2-weighted, and one T2*-weighted (magnetic susceptibility) image for each cranial study and a matrix of 10 images generated from 10 combinations of TE and TR for each body lymphoma study. All images were obtained with a 1.5 Tesla imaging system (GE Signa). Analyses were performed on over 100 MR image sets with a variety of pathologies. The cluster analysis was operated in an unsupervised mode and computational overhead was minimized by utilizing a table look-up approach without adversely affecting accuracy. Image data were first segmented into 2 coarse clusters, each of which was then subdivided into 16 fine clusters. The final tissue classifications were presented as color-coded anatomically-mapped images and as two and ...
A comparison of the loss mechanisms in screen-printed solar cells relative to buried contact cells and cells with photolithography-defined contacts is presented in this paper. Model calculations show that emitter recombination accounts for about 0.5% absolute efficiency loss in conventional screen-printed cells with low-sheet-resistance emitters. Ohmic contact to high-sheet-resistance emitters by screen-printing has been investigated to regain this efficiency loss. Our work shows that good quality ohmic contacts to high sheet-resistance emitters can be achieved if the glass frit chemistry and Ag particle size are carefully tailored. The melting characteristics of the glass frit determine the firing scheme suitable for low contact resistance and high fill factors. In addition, small to regular Ag particles were found to help achieve a higher open-circuit voltage and maintain a low contact resistance. ...
In this experiments, we established long-termed culture methods of bone marrow stromal cells for proliferation and differentiation of stem cells. And we selected some extracts which support maximal proliferation of stromal cells with this method. We conformed the synergic effects of herval mixture extracts for stromal cell growth. The proliferation of stromal cells was increased rather by the addition of mixture extracts than by addition of single strain extract. In the previous and cooperative experiments, we selected complex extracts which increased the number of nonadherent mononuclear cells. Different cytokine expression patterns were observed stromal cells cultured in the presence or absence of mixture extracts which support differentiation of nonadherent cells. Stimulation ...
Glypican-3 (GPC3), a membrane-bound heparan sulfate proteoglycan, is found to be overexpressed in hepatocellular carcinoma (HCC). The purpose of the present study was to investigate the possible role of GPC3 in the development of HCC. In this study, RNA interference (RNAi) with a GPC3 small hairpin RNA (GPC3 shRNA) was used to identify the effects of GPC3 on the regulation of malignant behaviors of HCC. MHCC97-H, a highly metastatic human HCC cell line in which GPC3 mRNA and protein levels were detected as the highest among the 4 HCC cell lines assessed in this study, and was thus selected as a cell model for in vitro and in vivo experiments. The results showed that down-regulation of GPC3 can significantly inhibit the proliferative and invasive ability of MHCC97-H. Compared with the parental HCC cells, GPC3-silenced cells exhibited attenuated capacities in ...
An exposure chamber is described for the quantifiable addition of fine and ultrafine aerosol particulate matter directly to cells and used to demonstrate the in vitro cytotoxicity of fine 1,4-naphthoquinone particles to murine lung epithelial cells. The electrostatic particulate dosage and exposure system (EPDExS) operates on the principle of electrostatic precipitation and is shown to deposit fine and ultrafine aerosol particles directly to cells with 100% efficiency for particle diameters in the range of 40-530nm. This range is not limited by the EPDExS, but rather by the aerosolization method used for this study. Numbers of particles deposited onto the cells are counted with a condensation particle counter, negating any need to calculate or estimate particle exposure. The process of particle introduction, assessed using Trypan blue dye exclusion, had no effect on cell viability. ...
We have employed both 31P nuclear magnetic resonance spectroscopy and two intracellular fluorescent pH indicator dyes to monitor the pH of the vacuole and cytoplasm of suspension-cultured...Full Text Available
Currently, human leukocyte antigen (HLA)-mismatched/haploidentical allografts have been validated as an alternative stem cell source for patients who have no immediate access to an HLA-matched related or unrelated donor. However, relapse remains a challenge after HLA-mismatched/haploidentical hematopoietic stem cell transplantation (HSCT) that is employed in the treatment of patients with hematological malignancies. In recent years, newly developed immunomodulatory strategies, which include prophylactic and therapeutic donor lymphocyte/natural killer (NK) cell infusion, donor selection based on NK alloreactivity/non-inherited maternal antigen (NIMA), immune reconstitution promotion, and application of exogenous cytokines, have made it possible to decrease the relapse rate and improve outco...
A red basil cell line (T2b) rich in rosmarinic acid (RA) was selected for the stable production of anthocyanins (ACs) in the dark. Cell suspension cultures were subjected to mechanical stress through increased agitation (switch from 90 to 150rpm) to determine the relationship between AC and RA accumulation. Cell extracts were analyzed by HPLC and LC-MS, and the resulting data were processed with multivariate statistical analysis. MS and MS/MS spectra facilitated the putative annotation of several complex cyanidin-based ACs, which were esterified with coumaric acid and, in some cases, also with malonic acid. It was also possible to identify various RA-related molecules, some caffeic and coumaric acid derivatives and some flavanones. Mechanical stress increased the total AC and RA contents, ...
Extracellular ATP stimulates transmembrane ion fluxes in the mouse macrophage cell line J774. In the presence of Mg2+, nonhydrolyzable ATP analogs and other purine and pyrimidine nucleotides do not elicit this response, suggesting the presence of a specific receptor for ATP on the macrophage plasma membrane. One candidate for such a receptor is the ecto-ATPase expressed on these cells. We, therefore, investigated the role of this enzyme in ATP-induced /sup 86/Rb+ efflux in J774 cells. The ecto-ATPase had a broad nucleotide specificity and did not hydrolyze extracellular ATP in the absence of divalent cations. /sup 86/Rb+ efflux was not blocked by inhibition of the ecto-ATPase and did not require Ca2+ or Mg2+. In fact, ATP-stimulated /sup 86/Rb+ efflux was inhibited by Mg2+ and correlated with the availability of ATP4- in the medium. In the absence of divalent cations, the slowly hydrolyzable ATP analogs adenosine ...
This paper describes a novel Fourier transform infrared (FTIR) spectroscopic method that can be used to rapidly screen soil samples from potentially hazardous waste sites. Samples are heated in a thermal desorption unit and the resultant vapors are collected and analyzed in a long-path gas cell mounted in a FTIR. Laboratory analysis of a soil sample by FTIR takes approximately 10 minutes. This method has been developed to identify and quantify microgram concentrations of explosives in soil samples and is directly applicable to the detection of selected volatile organics, semivolatile organics, and pesticides.
Solid-state nuclear magnetic resonance (NMR) has been used to explore the nanometer-scale structure of Nafion, the widely used fuel cell membrane, and its composites. We have shown that solid-state NMR can characterize chemical structure and composition, domain size and morphology, internuclear distances, molecular dynamics, etc. The newly-developed water channel model of Nafion has been confirmed, and important characteristic length-scales established. Nafion-based organic and inorganic composites with special properties have also been characterized and their structures elucidated. The morphology of Nafion varies with hydration level, and is reflected in the changes in surface-to-volume (S/V) ratio of the polymer obtained by small-angle X-ray scattering (SAXS). The S/V ratios of different Nafion models have been evaluated numerically. It has been found that only the water channel model gives the measured S/V ratios in the normal hydration ...
A electrochemical cell is described comprising an anode, a cathode, a solid polymer electrolyte; and a redox shuttle additive to protect the cell against overcharging and a redox shuttle additive to protect the cell against overcharging selected from the group consisting of: (a) a substituted anisole having the general formula shown in a figure (in an uncharged state): where R{sub 1} is selected from the group consisting of H, 0CH{sub 3}, OCH{sub 2}CH{sub 3}, and OCH{sub 2}phenyl, and R{sub 2} is selected from the group consisting of OCH{sub 3}, OCH{sub 2}CH{sub 3}, OCH{sub 2} phenyl, and O{sup {minus}}Li{sup +}; and (b) a di-anisole compound having the general formula shown in a second figure (in an uncharged state): where R is selected from the group consisting of -OCH{sup 3} and -CH{sub 3}, m is either 1 or 0, n is either 1 or 0, and X is ...
Selected applications of novel techniques in Agricultural Biotechnology, Health Food formulations and Medical Biotechnology are being reviewed with the aim of unraveling future developments and policy changes that are likely to open new markets for Biotechnology and prevent the shrinking or closing of existing ones. Amongst the selected novel techniques with applications in both Agricultural and Medical Biotechnology are: immobilized bacterial cells and enzymes, microencapsulation and liposome production, genetic manipulation of microorganisms, development of novel vaccines from plants, epigenomics of mammalian cells and organisms, and biocomputational tools for molecular modeling related to disease and Bioinformatics. Both fundamental and applied aspects of the emerging new techniques are being discussed in relation to their anticipated, marked impact on future markets and present policy changes that ...
In recent years, increased attention has been focused on the use of lasers in different fabrication steps of solar cells, in particular laser doping to form emitter and/or selective emitter. In this method the laser energy is used to melt silicon, allowing the diffusion of dopant atoms to occur in the liquid phase. The main advantage of this method is the localised nature of the laser beam, which melts and diffuses a limited area without heating the bulk, therefore reducing the possible degradation associated with high temperature processes. At the University of New South Wales a novel laser doping method was developed, which combines the formation of the selective emitter with a self-aligned metallisation pattern. Despite achieving high efficiencies, concerns arose regarding the adhesion ...
Silver iron oxide nanoparticles of fairly small size (average diameter approximately 1 nm) with narrow size distribution have been synthesized by the interaction of colloidal beta- Fe2O3 and silver nanoparticles. The surface morphology and size of these particles have been analyzed by using atomic force microscopy (AFM), field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). Their structural analysis has been carried out by employing x-ray diffraction (XRD), selected-area electron diffraction (SAED), optical and infrared (IR) spectroscopic techniques. The ageing of these particles exhibits the formation of self-assembly, possibly involving weak supramolecular interactions between Ag(I)O4 and Fe(III)O4 species. These particles display the onset of absorption in the near-infrared region and have higher absorption coefficient in the visible range compared to that of its precursors. Magnetic measurements ...
Early effects of boron neutron capture therapy (BNCT) on malignant glioma are characterized by reduction of the enhancement area and regression of the peritumoral edema radiologically. The aim of this study was to investigate the early histological changes of tumors and inflammatory cells after BNCT in the rat brain. Rats were treated with BNCT using boronophenylalanine (BPA) 7 days after implantation of C6 glioma cells. The tumors were assessed with magnetic resonance imaging and histopathological examination at 4 days after BNCT. The mean tumor volumes were 39#+-#2 mm"3 in the BNCT group and 134#+-#18 mm"3 in the control group. In the BNCT group, tumor cells showed a less pleomorphic appearance with atypical nuclei and mitotic figures. The Ki-67 labeling index was 6.5%#+-#4.7% in the BNCT and 35%#+-#3.8% in the control group. The reactions of the inflammatory cells were examined ...
Hematopoietic stem cells (HSCs) have remained at the forefront of stem cell research for the past 50 years, since the therapeutic potential of bone marrow transplantation was realized. Uniquely, among stem and progenitor cells, research progress has been made in parallel between the laboratory benchtop and hospital bedside during this period. Integral to this work has been the role of the transfusion medicine services in the collection, storage, and processing of HSCs. The next decade promises to bring further developments: with new fields of cellular therapies, stem cell vaccination, and stem cell drug testing opening up. This article summarizes exciting areas of research concerning the behavior and potential clinical applications of HSCs. For the purposes of clarity, we describe in turn the trafficking and transfer of HSCs; ex vivo expansion of HSC units from different sources; ...
Tissue hypoxia is a feature of cancer, heart disease and stroke, and imaging it may become clinically important. Copper-ATSM (ATSMH2 = 2,3-butanedione bis(N-methyl)thiosemicarb-azone), labelled with 60Cu, 62Cu or 64Cu, is selectively taken up in hypoxic cells in vitro and in vivo by a bioreductive mechanism, and is a prototype hypoxia imaging agent amenable to improvement. In vitro studies with several differently alkylated analogues of CuATSM show that hypoxia selectivity is a general property of complexes with two alkyl groups at the diketone backbone, offering a range of pharmacokinetic properties while retaining hypoxia selectivity. This pharmacokinetic control affords a route to development of second-generation hypoxia imaging agents with optimized properties for different clinical ap...
Ethnobotanical and chemotaxonomical studies for antiparasitic activity of Colombian Annonaceae were carried out. In vitro antiprotozoal activity of 36 extracts obtained from six different species was determined against promastigotes of three Leishmania species, epimastigotes of Trypanosoma cruzi and both chloroquine sensitive (F32) and resistant (W2) Plasmodium falciparum. Cytotoxic activity was evaluated in U-937 cells. Active extracts were selected according their selectivity index (SI). Extracts from Annona muricata, Rollinia exsucca, Rollinia pittieri and Xylopia aromatica were active against Leishmania spp. and Trypanosoma cruzi showing IC50 values lower than 25mg/ml. Hexane extract from Rollinia pittieri leaves was the most selective against Trypanosoma cruzi and Leishmania spp. (IS=...
Resistance and tolerance are two types of host defense mechanisms that increase fitness in response to fungi. Several genetic polymorphisms in pattern recognition receptors, most remarkably Toll-like receptors (TLRs), have been described to influence resistance and tolerance to aspergillosis in distinct clinical settings. TLRs on dendritic cells pivotally contribute in determining the balance between immunopathology and protective immunity to the fungus. Epithelial cells also contribute to this balance via selected TLRs converging on indoleamine-2,3-dioxygenase (IDO). Studies in experimental hematopoietic transplantation confirmed the dichotomy of pathways leading to resistance and tolerance to the fungus providing new insights on the relative contribution of the hematopoietic/nonhematopoi...
The contention of this commentary, focused on the vestibulocerebellum (particularly the flocculus), is that the great importance for our understanding of cerebellar organization in terms of climbing fiber zones, begun years ago by Voogd [1969, 2011] and Oscarsson [1969], needs to be matched by coming more to grips with the other fundamental geometrical organization of the cerebellum, the parallel fibers. The central issue is the selection of those parallel fiber signals to be transformed into Purkinje cell activity in the different zones. At present, in comparison to our knowledge of vestibulocerebellar climbing fiber inputs, the deficiencies in our knowledge of the zonal anatomy and physiology of vestibulocerebellar mossy fibers and granule cells are glaring. The recent emphasis on molecu...
Thermophotovoltaic (TPV) systems are attractive possibilities for direct thermal-to-electric energy conversion, but have typically required the use of black body radiators operating at high temperatures. Recent advances in both the understanding and performance of solid rare-earth oxide selective emitters make possible the use of TPV at temperatures as low as 1200K. Both selective emitter and filter system TPV systems are feasible. However, requirements on the filter system are severe in order to attain high efficiency. A thin-film of a rare-earth oxide is one method for producing an efficient, rugged selective emitter. An efficiency of 0.14 and power density of 9.2 W/KG at 1200K is calculated for a hypothetical thin-film neodymia (Nd2O3) selective emitter TPV system that uses radioisotope decay as the thermal energy source.
Nitroaromatic radiosensitizers become metabolically bound preferentially to hypoxic cells and at least 10/sup 9/ adducts/cell can be tolerated as non-toxic. EMT-6 tumor cells have been incubated in hypoxia in the presence of /sup 3/H-Misonidazole and /sup 125/I-Azomycin Riboside for various times and the amount of /sup 3/H or /sup 125/I bound/cell was determined. Cells were stored as monolayers at 25"0C for up to 96 hr to accumulate radioactive decays and transferred at various times to 37"0C for colony-forming assays. No radiation inactivation was measured in cells which had incorporated at least 10/sup 6/ /sup 3/H or 10/sup 5/ /sup 125/I atoms. Previous studies had shown that -- 1% of MISO adducts to EMT-6 cells was associated with cellular DNA. These data indicate that the radiation-induced damage produced by these quantities of bound ...
It is possible to produce energetic beams of radioactive nuclei, as secondary beams, from the heavy-particle compound accelerator called BEVALAC. These beams can be focused into experimental areas without significant contamination using suitable magnetic filters and proper beam-optics. Properly selected high-energy beams of radioactive nuclei (those which defay by positron emission) can provide a truly unique opportunity to evaluate the effectiveness of these beams in localizing the Bragg peak on a tumor volume - necessary in heavy-particle therapy. Preliminary data are presented here to demonstrate the possible use of these beams in radiotherapy treatment-planning verification.
Pittston Coal Company recognized the potential economic benefit of improving process efficiency with increased capacity at it`s U.K. No. 1 Coal Preparation Plant. Accordingly, extensive research, both domestically and internationally, was conducted to select the appropriate technologies to achieve the desired circuit in the most cost effective manner while, at the same time, sacrificing neither structural integrity nor process performance. Large diameter heavy media cyclone technology was combined with highly efficient banana type screens and improved high intensity magnetic separators to create a coordinated process circuit that provided high efficiency at very high capacities in an economically attractive package.
A laser-induced plasma of alkali atoms was studied with a view to efficient recovery of isotope ions, with small charge exchange losses. The electron temperature was measured by the double-probe method for several kinds of excitation schemes, which gave the relationship between temperature and the energy given to ions by laser photons. A charge exchange process between lithium isotopes was also studied in an electromagnetic field. It was shown that optimum electrostatic and magnetic field strength exist which maximise the 'separative power'.
A non-invasive, wide-band electromagnetic (EM) impedance difference system for shallow subsurface electrical structure characterization in environmental and engineering problems has been developed at the Lawrence Berkeley National Laboratory (LBNL). Electrical parameters of interest are electrical conductivity and dielectric permittivity that are deduced from the impedance difference data. The prototype system includes a magnetic loop transmitter, which operates between 0.1 MHz and 100 MHz, an electrical dipole antenna for observing the electric field, and a loop antenna for measuring the magnetic field.All antennas are mounted on a cart made of non-metallic material for easy movement of the whole array for profiling. Surface EM impedance difference is obtained by taking the difference of the ratios of the electric fields to the magnetic fields at selected frequencies at two different levels. Numerical ...
Extraskeletal Ewing's sarcoma (ES) and primitive neuroectodermal tumor (PNET) are widely regarded as clinically and histologically identical tumors which consist of small blue round cells. Extraskeletal ESs/PNETs usually occur in the deep soft tissues of the paraspinal region, chest wall, or lower extremities. However, superficially located cases, so-called cutaneous ESs/PNETs, are exceedingly rare, and the vast majority of the reported cases present as a single small mass. We present magnetic resonance imaging (MRI) findings and clinical course of a unique case of primary cutaneous ES/PNET presenting as numerous huge masses with severe ulceration on them. (orig.)
A concept of direct energy recovery system applying an alternating or rotating magnetic field is proposed for a negative-ion-based neutral beam injection system (NNB) to heat a plasma and/or drive a plasma current in a fusion reactor. Nearly same amounts of residual positive and negative hydrogen-isotope ion beams with beam energy of {approx}1 MeV are produced in an NNB using a gas neutralizing cell. Consequently, a recovered energy is obtained directly in the form of ac electric power, if these positive- and negative-ion beams are alternated or rotated and introduced to two or more recovery electrodes in turn by an alternating or rotating magnetic field. This concept will greatly reduce a technological difficulty in regeneration of a recovered electric energy with such a very high voltage. (author).
Four 10 MW, highly-stabilized power supply modules have been installed at the National High Magnetic Field Laboratory in Tallahassee, FL, to energize water-cooled, resistive, high-field research magnets. The power supply modules achieve a long term current stability if 10 ppM over a 12 h period with a short term ripple and noise variation of <10 ppM over a time period of one cycle. The power supply modules can operate independently, feeding four separate magnets, or two, three or four modules can operate in parallel. Each power supply module consists of a 12.5 kV vacuum circuit breaker, two three-winding, step-down transformers, a 24-pulse rectifier with interphase reactors, and a passive and an active filter. Two different transformer tap settings allow rated dc supply output voltages of 400 and 500 V. The rated current of a supply module is 17 kA and each supply module has a one-hour overload capability of 20 kA. The ...
Understanding of probiotic-induced regulatory gene expression and networking is critical to further explore their roles in controlling infection. Transcriptional profile of selected innate immune genes in primary bovine intestinal epithelial cells was assessed over a time course of incubation with the probiotic Lactobacillus plantarum 299v. Based on gene expression results, a time point was chosen to prime epithelial cells with the probiotic prior to infection with rotavirus. Plaque assays and genomic analysis provided the basis for establishing the efficacy of probiotics in preventing a rotaviral infection. Plaque assays revealed that the probiotic is capable of decreasing (at least by 100-fold) the levels of live virus when the cells were primed with the probiotic. Results from gene expr...
This thesis deals with the evaluation of Solar Grade Silicon (SoG-Si) purified by different techniques, and also the fabrication and characterization of high efficiency and advanced bifacial solar cells. In the beginning of Chapter 1, various SoG-Si production methods relevant for this work are qualitatively described. The three feedstock materials used in this work are from the Fluidized Bed Reactor (FBR) process, metallurgical feedstock-I and feedstock-II process. In metallurgical feedstock-I, the lifetime of the minority charge carriers in multicrystalline silicon (mc-Si) samples at the grain boundaries are found to be higher than the grains themselves possibly due to lower resistivities in the grain boundaries. The efficiency of the best solar cell obtained using the mc-Si metallurgical feedstock-I is 16.1%. It has been identified that the fast light induced degradation, whose magnitude is lower than that of a reference ...
This study provides an analysis of potential changes that may take place in a Uranium Mill Tailings Remedial Action (UMTRA) Project disposal cell cover system as a result of plant biointrusion. Potential changes are evaluated by performing a sensitivity analysis of the relative impact of root penetrations on radon flux out of the cell cover and/or water infiltration into the cell cover. Data used in this analysis consist of existing information on vegetation growth on selectedcell cover systems and information available from published studies and/or other available project research. Consistent with the scope of this paper, no new site-specific data were collected from UMTRA Project sites. Further, this paper does not focus on the issue of plant transport of radon gas or other contaminants out of the disposal cell cover though it is acknowledged that such ...
This study provides an analysis of potential changes that may take place in a Uranium Mill Tailings Remedial Action (UMTRA) Project disposal cell cover system as a result of plant biointrusion. Potential changes are evaluated by performing a sensitivity analysis of the relative impact of root penetrations on radon flux out of the cell cover and/or water infiltration into the cell cover. Data used in this analysis consist of existing information on vegetation growth on selectedcell cover systems and information available from published studies and/or other available project research. Consistent with the scope of this paper, no new site-specific data were collected from UMTRA Project sites. Further, this paper does not focus on the issue of plant transport of radon gas or other contaminants out of the disposal cell cover though it is acknowledged that such ...
Transplantation procedures using intraparenchymal injection of stem cells result in tissue injury in addition to associated surgical risks. Intravenous injection of mesenchymal stem cells gives engraftment to lesions, but the method has low efficiency and specificity. In traumatic brain injuries (TBI), there is a transient breakdown of the blood-brain barrier and an inflammatory response, which increase migration of cells from blood to parenchyma. The aim of this investigation was to analyze the effect of intra-arterial administration on cellular engraftment. Experimental TBI was produced in a rat model. Endovascular technique was used to administer human mesenchymal stem cells in the ipsilateral internal carotid artery. Evaluation of engraftment and side effects were performed by immunohistochemical analysis of the brain and several other organs. The results were compared to intravenous administration ...
The effect of abatacept, a selective T-cell co-stimulation modulator, on vaccination has not been previously investigated. In this open-label, single-dose, randomized, parallel-group, controlled study,...Full Text Available
Background2-Methylthioadenosine 5'-triphosphate (2-MeSATP), formerly regarded as a specific P2Y (metabotropic) purinergic receptor agonist, stimulates Ca2+ influx and...Full Text Available
BackgroundWhen eukaryotic cells are deprived of amino acids, uncharged tRNAs accumulate and activate the conserved GCN2 protein kinase. Activated Gcn2p up-regulates the general amino...Full Text Available
A mutant strain of Saccharomyces cerevisiae (D10-ER1) has been isolated after a two-step mutagenesis of strain 4059-358D (SUC 1) using ethyl methane sulfonate. Cells of this new strain produced a level...Full Text Available
...) Abstract: Fluorescence microscopic imaging is widely used in biomedical research to study molecular and cellular processes in cell culture or tissue samples. This is motivated by the high inherent sensitivity of fluorescence techniques, the spatial resolution that compares favorably with cellular dimensions, the stability of the fluorescent labels used and the sophisticated strategies that have been developed for selectively labeling target molecules. More recently, two and ...
The Self Actuated Shutdown System (SASS) is now under development for use in a large scale FBR, in order to establish the passive shutdown capability against the postulated ATWS events, i.e. ULOF, UTOP and ULOHS. The function of SASS makes use of the safety characteristics of a liquid metal cooled FBRs such as a large subcooling and low pressure system. The insertion of the control rods insertion is assured even in the most conservative seismic design condition by employing articulate rods and the SASS will be installed into the detaching mechanism employing a curie point the magnet alloy. ULOF analysis of the present FBR shows that coolant boiling inception is prevented if a control rod of the SASS is detached at the uppermost temperature of 680degC for the Curie point magnet, and after the reactor shutdown the coolant temperature is kept below 600degC by the pony motor flow. Therefore the SASS will establish passive shutdown capability ...
The specification describes a semiconductor solar cell and fabrication process therefor wherein a thin N-type gallium arsenide layer is deposited on a larger P-type substrate layer which is selected from the group of III-V ternary compounds consisting of aluminum phosphide antimonide, AlPSb, and aluminum indium phosphide, AlInP. P-type impurities are diffused from the substrate layer into a portion of the thin N-type gallium arsenide layer to form P-type region wherein which defines a PN junction in the thin gallium arsenide layer. Thus, the quantity of gallium arsenide required to provide this PN photovoltaic junction layer in the cell is minimized, and th P-type substrate serves as a high bandgap window layer for the cell. Such high bandgap of this window material is especially well suited for efficiently transmitting the blue spectrum of sunlight to the PN junction, thus enhancing the power ...
X-ray magnetic circular dichroism (XMCD) was used to probe the existence of induced magnetic moments in yttrium iron garnet (YIG) films in which yttrium is partly substituted with lanthanum, lutetium or bismuth. Spin polarization of the 4d states of yttrium and of the 5d states of lanthanum or lutetium was clearly demonstrated. Angular momentum resolved d-DOS of yttrium and lanthanun was shown to be split by the crystal field, the two resolved substructures having opposite magnetic polarization. The existence of a weak orbital moment involving the 6p states of bismuth was definitely established with the detection of a small XMCD signal at the Bi M{sub 1}-edge. Difference spectra also enhanced the visibility of subtle changes in the Fe K-edge XMCD spectra of YIG and {l_brace}Y, Bi{r_brace}IG films. Weak natural X-ray linear dichroism signatures were systematically observed with all iron garnet films and with a bulk YIG ...
Magnetic particles have become very promising materials for drug delivery. However, preparation of magnetite particles with high surface area, biocompatibility, strong magnetic response, and suitable particle size still remains a major challenge. In this report, magnetite nanocrystal clusters with high surface areas were fabricated through a solvothermal process by introducing ammonium acetate as a porogen and trisodium citrate as a surface modification agent. The porosity, which was controlled by the reactant concentration, has been investigated in detail. The surface area of the nanocrystal clusters was as high as 141?m(2) g(-1) . Ibuprofen, as a model drug, was entrapped into the magnetite carriers. The interfacial interaction between the carboxylic groups on the drug molecules and the carboxylate groups on the carriers enhanced the loading efficiency. Low cytotoxicity in MCF-7 cell and in vitro constant drug release ...
The effect of the external pH on the intracellular pH in mung bean (Vigna mungo (L.) Hepper) root-tip cells was investigated with the T P nuclear magnetic resonance (NMR) method. The T P NMR spectra showed three peaks caused by cytoplasmic G-6-P, cytoplasmic Psub(i) and vacuolar Psub(i). The cytoplasmic and vacuolar pHs could be determined by comparing the Psub(i) chemical shifts with the titration curve. When the external pH was changed over a range from pH 3 to 10, the cytoplasmic pH showed smaller changes than the vacuolar pH, suggesting that the former is regulated more strictly than the latter. The H -ATPase inhibitor, DCCD, caused the breakdown of the mechanism that regulates the intracellular pH. H -ATPase appears to have an important part in the regulation of the intracellular pH.
Because every cell within the body has the same genetic information, a significant problem in biology is to understand how cells within a tissue express genes selectively. A sophisticated network of physical and biochemical signals converge in a highly orchestrated manner to bring about the exquisite regulation that governs gene expression in diverse tissues. Thus, the ultimate decision of a cell to proliferate, express tissue-specific genes, or apoptose must be a coordinated response to its adhesive, growth factor, and hormonal milieu. The unifying hypothesis examined in this overview is that the unit of function in higher organisms is neither the genome nor the cell alone but the complex, three-dimensional tissue. This is because there are bidirectional connections between the components of the cellular microenvironment (growth factors, hormones, and extracellular matrix) and the ...
In this study, the shear viscosities of wood?plastic composites (WPC)/supercritical CO2 (sc-CO2) solutions at different die temperatures and sc-CO2 contents were measured by a slit die attached on a single-screw extrusion system. A theoretical model based on the Carreau-Yasuda model and Arrhenius equation was then developed to describe the shear-thinning behavior of the WPC/sc-CO2 solution. This model was incorporated into a finite element method software, POLYFLOW, to simulate the pressure and velocity field of WPC/sc-CO2 solution flowing through a foaming die. Based on the simulation results, the pressure drop rate and the location of the supersaturation point were estimated to investigate the cell nucleation. The saturation pressure of sc-CO2 in WPC was determined by a magnetic suspensi...
The objective was to characterize imaging findings of benign notochordal cell tumors (BNCTs). Clinical and imaging data for 9 benign notochordal cell tumors in 7 patients were reviewed retrospectively. Conventional radiographs (n = 9), bone scintigrams (n = 2), computed tomographic images (n = 7), and magnetic resonance images (n = 8) were reviewed. Eight of the 9 lesions were stained with hematoxylin-eosin and microscopically examined. There were 3 male and 4 female patients with an age range of 22 to 55 years (average age, 44 years). Two patients had two lesions at different sites. The lesions involved the cervical spine in 4 patients, the lumbar spine in 2, the sacrum in 2, and the coccyx in 1. The most common symptom was mild pain. The lesions of 2 patients were found incidentally during imaging studies for unrelated conditions. Five patients underwent surgical procedures. One patient died of surgical complications. All ...
... Title : Refining the Magnetic Forming Capability. ... Abstract : The purpose of this project was to refine the in-house magnetic forming capability. ...
in pulse applications such as magnetic forming. ... In magnetic-forming electric circuitry, the ..... Aspects of Electrohydraulic land Magnetic Forming. ...
The marked difference between the intra- and extracellular "3"1P NMR chemical shifts of various phosphoryl compounds when added to a red cell suspension may be largely understood in terms of the effects of hemoglobin on the "3"1P NMR chemical shifts. The presence of [oxy- or (carbonmonoxy)-] hemoglobin inside the red cell causes the bulk magnetic susceptibility of the cell cytoplasm to be significantly less than that of the external solution. This difference is sufficient to account for the difference in the intra- and extracellular chemical shifts of the two phosphate esters trimethyl phosphate and triethyl phosphate. However, in the case of the compounds dimethyl methylphosphonate, diethyl methylphosphonate, and trimethylphosphine oxide as well as the hypophosphite, phenylphosphinate, and diphenylphosphinate ions, hemoglobin exerts an additional, much larger, effect, causing the "3"1P NMR resonances ...
This report covers the first year of operation of a fuel cell power plant, installed by PPL Spectrum, Inc. (PPL) under contract with the United States Coast Guard (USCG), Research and Development Center (RDC). The fuel cell was installed at Air Station Cape Cod in Bourne, MA. The project had the support of the Massachusetts Technology Collaborative (MTC), the Department of Energy (DOE), and Keyspan Energy. PPL selected FuelCell Energy, Inc. (FCE) and its fuel cell model DFC{reg_sign}300 for the contract. Grant contributions were finalized and a contract between PPL and the USCG for the manufacture, installation, and first year's maintenance of the fuel cell was executed on September 24, 2001. As the prime contractor, PPL was responsible for all facets of the project. All the work was completed by PPL through various subcontracts, including the primary ...
Within the framework of the French inter lab SPACT project (Fuel Cell Systems for Transportation Applications), the behavior of a 5 kW PEM fuel cell stack, fed by humidified hydrogen and compressed air, is investigated in a test platform at Belfort, France. A set of polarization curves are recorded, under various conditions of stack temperature, gas pressure, and stoichiometry rates, in order to obtain a kind of cartography, representing the static stack performance. Initially, the tests are defined considering experimental design techniques. In order to study the relative impacts of the physical factors on the fuel cell voltage, some polarization curve results are selected from the static tests available applying experimental design methodology. First, several analyses are used to estimate the impact of the stack temperature, gas pressure, and stoichiometry rate on the fuel cell ...
Exposures from most natural and artificial sources, with the exception of those from medical radiology, are received at average dose rates of only a few microsieverts a day. Such risks as may be caused by these exposures are most unlikely to be determined with precision directly by epidemiological studies of populations exposed at these low rates. They may, however, be reliably inferred from the observed risks of exposure to rather larger doses delivered at higher dose rates in the light of the increasing knowledge of the phenomena involved in the initial cellular damage, the extent to which such damage is incorrectly repaired, and the processes which intervene between the genetic or other harm to cells and the likelihood of its final expression in inherited abnormality, in cancer development, or in defective foetal or embryonic growth. Current studies are of great importance, therefore, in examining the circumstances in which coding sections of the chromosomal DNA ...
In drug development, Caco-2 cells are often employed to study the influence of membrane transporters on drug permeability. The aim of the current study was to characterize permeability and kinetic parameters of selected organic anionic compounds in Caco-2 cells, and to investigate whether the Caco-2 cell line may be used as an overall model to predict interactions on multiple membrane transporters in the intestine. Taurocholic acid (TCA) and estrone-3-sulfate (E(1) S) were used as model substrates. Possible inhibitors studied were TCA, E(1) S, taurolithocholic acid, fluvastatin, and glipizide. The effects of these compounds on initial uptake, apparent permeability, and intracellular end-point accumulations of the probe substrates were studied. Both interactions on apical and basolateral influx transporters were observed. These interactions were proposed to be mediated mainly by the apical ...
We are continuing to study the suitability of modified thermal-battery technology as a potential power source for geothermal borehole applications. Previous work focused on the LiSi/FeS{sub 2} couple over a temperature range of 350 C to 400 C with the LiBr-KBr-LiF eutectic, which melts at 324.5 C. In this work, the discharge processes that take place in LiSi/CsBr-LiBr-KBr eutectic/FeS{sub 2} thermal cells were studied at temperatures between 250 C and 400 C using pelletized cells with immobilized electrolyte. The CsBr-LiBr-KBr eutectic was selected because of its lower melting point (228.5 C). Incorporation of a quasi-reference electrode allowed the determination of the relative contribution of each electrode to the overall cell polarization. The results of single-cell tests and limited battery tests are presented, along with preliminary data for battery stacks tested in a simulated ...
In the current wind turbine generation system, there are substantial problems such as the maximum power of the wind turbine cannot be obtained under the fluctuating wind speed, high in cost and low in annual net electricity production (due to mismatch between a generator and a wind turbine). A new wind turbine generator optimized for the wind turbine output is presented in order to solve such problems. This wind turbine generator consists of a permanent magnet generator, a reactor and a rectifier, and uses neither a control circuit which requires standby electricity nor a PWM converter having a switching element. By selecting most appropriate combination of the permanent magnet generator having multiple windings and the reactor connected in series with each winding, the maximum output of the wind turbine can be obtained without using a control circuit. The new wind turbine generator was directly coupled with the straight ...
Retroelements constitute a large part of the human genome. These sequences are mostly silenced in normal cells, but genome-wide DNA hypomethylation in cancers might lead to their re-expression. Whether this re-expression really occurs in human cancers is largely unkown. We therefore investigated expression and DNA methylation of several classes of retroelements in human prostate cancer tissues and cell lines by quantitative reverse transcription-polymerase chain reaction and pyrosequencing, respectively. The most striking finding was strong and generalized increased expression of the HERV-K_22q11.23 provirus in cancers, including de novo expression of a spliced accessory Np9 transcript in some tumors. In parallel, DNA methylation in the long terminal repeat (LTR) decreased. Conversely, HER...
The efficiency of electric power generation by dye-sensitized mesoscopic photovoltaic cells has been progressing steadily over the last years reaching now 11% in full sunlight. An important question for practical applications concerns the stability of these devices under prolonged exposure to light or heat. Strikingly stable operation can be obtained by judicious selection of the sensitizer, electrolyte and sealant rendering feasible a service life of at least 20 years under normal outdoor conditions. The sensitizer playing a central role in the light energy conversion process, we analyze the kinetic requirements for it to sustain the required one hundred million turnovers. We also review recent results on the use of self-assembled monolayers of amphiphilic sensitizers and co-adsorbents to enhance the thermal robustness of the device. (author)
This article describes the complete microsporogenesis and pollen formation in cassava (Manihot esculenta Crantz) at the various developmental stages (pollen mother cell, meiosis, tetrads, early free spore, mid uninucleate, late uninucleate, binucleate and mature pollen grain). Light microscopy, transmission electron microscopy and confocal laser scanning microscopy were used for the study. Floral bud size and other inflorescence characteristics were correlated with specific stages of the microspore development. This association allows a rapid selection of floral buds with similar microspore developmental stages, useful when a large number of homogeneous cells are needed for analysis and for in vitro induction of androgenesis. This article also compares methods for digestion the exine wall ...
Dissolved microcystins (MCs) are regularly present in water dominated by microcystin-producing, bloom-forming cyanobacteria. In vitro experiments with environmentally feasible concentrations (5 ? 10?7 M) of the three most common microcystins, MC-LR, MC-RR, and MC-YR, revealed that they influence the metabolism of different representative phytoplanktons. At light intensities that are close to the cyanobacterial bloom environment (50??mol m?2 s?1), they produce morphological and physiological changes in both microcystin-producing and -nonproducing Microcystis aeruginosa strains and also have similar effects on the green alga Scenedesmus quadricauda that is frequently present in cyanobacterial blooms. All three microcystin variants tested induce cell aggregation, increase in cell volume, and ...
In order to get the separation of natural isotopes of lithium by electrolytic amalgamation, an electrolytic cell with a confined mercury cathode was used to obtain data for the design of a separation stage. The initial work was followed by the design of a moving mercury cathode electrolytic cell and three experiments with six batches stages were performed for the determination of the elementary separation factor. The value obtained, 1.053, was ill agreement: with the specialized literature. It was verified in all experiments that the lithium - 6 isotope concentrated in the amalgam phase and that the lithium - 7 isotope concentrated in the aqueous phase. A stainless-steel cathode for the decomposition of the lithium amalgam and the selective desamalgamation were also studied. In view of the results obtained, a five stages continuous scheme was proposed. (author)
Peptide sequences such as lysine-arginine-serine-arginine (KRSR) selectively bind transmembrane proteoglycans (e.g. heparin sulfate) of osteoblasts (bone-forming cells) and are, therefore, actively being investigated for orthopedic applications. Further, nanophase materials (or materials with grain or particle sizes less than 100 nm) are promising new materials that promote new bone growth more than compared to conventional (that is, micron grain or particle size) materials. To combine the above two promising approaches for improving orthopedic implants, the objective of this in vitro study was to functionalize titanium (Ti) surfaces (both nanophase and conventional) with KRSR peptides and study their osteoblast cell adhesive properties. Materials were characterized by X-ray photoelectron ...
Keratinocyte growth factor receptor (KGFR) and fibroblast growth factor receptor (FGFR) 2c share identical amino acid sequences, except for a 46-amino acid domain in the extracellular region. Monoclonal antibodies (MAbs) specific to KGFR have not been reported nor are commercially available. In this study, we generated murine MAbs specific to KGFR in non-obese diabetic (NOD) mice using a modified Repeated Immunizations at Multiple Sites (RIMMS) technology. Stable cell lines expressing the full-length human KGFR or FGFR2c were produced to facilitate the identification of KGFR-specific MAbs. Following the initial screening of hybridoma clones with a fluorescence-based, confocal cell detection method and ELISA, KGFR-specific MAbs were selected and confirmed by flow cytometry and Western blot ...
Heavily doped emitters with low saturation current density are of particular interest for selective emitter solar cells. These emitters can be obtained by laser doping through the phosphosilicate glass layer formed after thermal diffusion from POCl3 gas. The experimental results show that in contrast to purely POCl3 furnace-diffused emitters, the saturation current density of laser-doped emitters does not increase linearly as sheet resistance decreases, but rather features two distinct regimes. In one of these regimes, the saturation current density is found to decrease as the sheet resistance decreases, reaching values lower than those of furnace emitters. This peculiar behaviour was explained by both qualitative analysis and numerical simulations.
A prospective comparative study with pathology was performed to assess the clinical value of Computed Tomography (CT) and endoscopic ultrasound (EUS) for nodal staging in lung cancer. A total of 329 nodal stations were dissected or sampled and 755 lymph nodes were examined at histology. On a pre-station basis, CT had greater sensitivity (74%) than EUS (56%), but EUS was more specific (83% versus 93%). The accuracy rates of the two techniques were similar. In conclusion, endoscopic ultrasound should be part of a routine preoperative diagnostic approach to non-small-cell lung cancer., because of its high specificity. Results can be improved when EUS and CT are combined., which suggests that these imaging modalities should be used together in selected patients for the noninvasive staging of non-small-cell lung cancer to identify local lymphatic spread.
This talk will summarize key features of three conceptual fusion neutron test facilities designed in the early 1980s: TASKA,^1 TDF,^2 and TASKA-M.^3 Motivated by the accessibility and maintainability of cylindrical geometry, these magnetic-mirror designs possess a simple central cell, as in a fusion neutron test facility based on the gas dynamic trap (GDT).^4 The TASKA-M design, like today's GDT designs, included the injection of neutral beams into the central cell to create a sloshing-ion distribution that gives density peaks near the materials test modules. In TASKA and TDF, the minimum-B end-cell designs contained thermal barriers, regions of low electrostatic potential to reduce electron flow between central cell and end cells. Thermal barriers improve performance but require more complicated input power systems, and their physics basis is less well ...
Magnetic separation of several classes of antibiotics was investigated using electrochemical magnetic seeding. Electrocoagulation with a sacrificial anode followed by addition of magnetite particles was applied for the magnetic seeding of antibiotics. With electrochemical magnetic seeding using an iron anode, tetracycline antibiotics (oxytetracycline, chlortetracycline, doxycycline and tetracycline) and cephalosporin antibiotic (cefdinir) were rapidly removed from synthetic wastewater by magnetic separation using a neodymium magnet. Iron and aluminium anodes were suitable for magnetic seeding of the antibiotics. The results indicated that the ability of antibiotics to form strong complex with iron and aluminium allowed the higher removal by magnetic separation. This method would be appropriate for rapid treatment of ...
BackgroundIn recent years, near-infrared fluorescence (NIRF)-labeled iron nanoparticles have been synthesized and applied in a number of applications, including the labeling of human cells for monitoring the engraftment process, imaging tumors, sensoring the in vivo molecular environment surrounding nanoparticles and tracing their in vivo biodistribution. These studies demonstrate that NIRF-labeled iron nanoparticles provide an efficient probe for cell labeling. Furthermore, the in vivo imaging studies show excellent performance of the NIR fluorophores. However, there is a limited selection of NIRF-labeled iron nanoparticles with an optimal wavelength for imaging around 800 nm, where tissue autofluorescence is minimal. Therefore, it is necessary to develop additional alternative NIRF-labeled iron nanoparticles for application in this area.ResultsThis study manufactured 12-nm DMSA-coated Fe3O4 nanoparticles labeled with a ...
Inverted growth and the development of associated cell processing, are likely to offer a significant degree of freedom for improving the performance of many III-V multijunction cascades and open new avenues for advanced multijunction concepts. This is especially true for the development of high-efficiency Al[sub 0.37]Ga[sub 0.63]As/GaAs cascades where the high growth temperatures required for the AlGaAs top cell growth can cause the deterioration of the tunnel junction interconnect. In the approach of inverted-grown AlGaAs/GaAs cascade cells, the AlGaAs top cell is grown first at 780 [degree]C and the GaAs tunnel junction and bottom cell are grown at 675 [degree]C. After the inverted growth, the AlGaAs/GaAs cascade structure is selectively removed from the parent substrate. The feasibility of inverted growth is demonstrated by a fully-processed, inverted-grown, ...
Polymeric coated ferromagnetic carriers with an absorbed layer of octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) diluted by tributyl phosphate (TBP) are being evaluated for application in the separation and the recovery of low concentrations of americium, plutonium, and uranium from nuclear waste solutions. Due to their chemical nature, these extractants selectively complex americium and plutonium contaminants onto the particles and the complexed particles can be recovered from the solution using a magnet. Physical and chemical characterization of the extractant-absorbed particles were performed by gamma and liquid scintillation counting, scanning electron microscopic (SEM) micrograph, and other physical measurements. Plutonium, americium, and uranium separations have been performed at various HNO{sub 3} and HCl concentrations. Parameters were studied to determine the limitations and capacity of the process. The status of the ...
This Report includes copies of transparencies and notes from the presentations made at the Center for Accelerator Physics at Brookhaven National Laboratory Editing and changes to the authors` contributions in this Report were made only to fulfill the publication requirements. This volume includes notes and transparencies on nine presentations: ``The Energy Exchange and Efficiency Consideration in Klystrons``, ``Some Properties of Microwave RF Sources for Future Colliders + Overview of Microwave Generation Activity at the University of Maryland``, ``Field Quality Improvements in Superconducting Magnets for RHIC``, ``Hadronic B-Physics``, ``Spiking Pulses from Free Electron Lasers: Observations and Computational Models``, ``Crystalline Beams in Circular Accelerators``, ``Accumulator Ring for AGS & Recent AGS Performance``, ``RHIC Project Machine Status``, and ``Gamma-Gamma Colliders.``
New technologies are needed to reduce the current high rate of well abandonment. Improved sweep efficiency, reservoir conformance, and permeability modification can have a significant impact on oil recovery processes. Microorganisms can be used to selectively plug high-permeability zones to improve sweep efficiency and impart conformance control. Studies of a promising microbial system for polymer production were conducted to evaluate reservoir conditions in which this system would be effective. Factors which can affect microbial growth and polymer production include salinity, pH, temperature, divalent ions, presence of residual oil, and rock matrix. Flask tests and coreflooding experiments were conducted to optimize and evaluate the effectiveness of this system. Nuclear magnetic resonance imaging (NMRI) was used to visualize microbial polymer production in porous media. Changes in fluid distribution within the pore system of the core were ...
Single-crystalline cadmium selenide nanoparticles were obtained using high-temperature solution phase synthesis (HTSPS) synthesis. X-Ray powder diffraction and transmission electron microscopy were used to confirm the crystallinity and morphology of the resulting nanoparticles. To study the action of CdSe on antioxidant activity, we selected two biotechnological important strains of microalgae: cyanobacteria Spirulina platensis and red microalgae Porphyridium cruentum. In the case of Porphyridium cruentum, the obtained results demonstrated an increase in the productivity. For Spirulina platensis, the presence of the compound in the cultivating medium decreased the productivity of cyanobacteria.
This book contains the results of an architectural evaluation of building examples with integrated photovoltaic. Danish Building and Urban Research and Danish Technological Institute conducted the work within the framework of Solar Energy Centre Denmark. Seven examples are selected to inspire Danish architects and building owners to use PV in the building environment. The examples come from Denmark and countries (the Netherlands and Germany) with similar building traditions, climate and solar conditions. All the examples demonstrate architectural concepts that integrate photovoltaic as a natural part of the building envelope. (BA)
This study was conducted to investigate the decomposition of three {gamma}-irradiated antibiotics (e.g., tetracycline, sulfamethazine, and lincomycin) and to compare the toxic effects on Daphnia magna, Vibrio fischeri, and Pseudokirchneriella subcapitata. The median cell growth inhibition concentrations (IC{sub 50}) of tetracycline, lincomycin, and sulfamethazine for P. subcapitata dramatically increased (e.g., toxicity decreased) after radiolysis. The results demonstrated that {gamma}-radiation treatment was efficient to decompose antibiotics and thereby their toxicity on P. subcaptitata remarkably decreased due to reduced parent compounds.
Abstract First results showing the viability of combining laser chemical processing (LCP) and aerosol jet printing (AJP) technologies to produce a high-efficiency front side for silicon solar cells are presented. LCP simultaneously opens the anti-reflection coating (ARC) and highly dopes the underlying silicon to create a selective emitter, while AJP is the first in a two-step fine-line contact formation procedure. The electrical properties as well as the morphology of the resulting structures are presented. Performance similar to that achieved with evaporated TiPdAg metallization is demonstrated. Copyright 2010 John Wiley & Sons, Ltd.
A magnetic tape consisting of oil-shale Fischer assay data for selected well cores in the Piceance Creek Basin was prepared as a supplement to NTIS tape PB-230 607/AS. Both tapes serve as a data base for calculating oil-shale resources (Pitman, 1981). The tape is in standard IBM format and has the following specifications: EBCDIC (IBM standard), card-image, blocksize 1720 (blocked 20 to 1), record length 86, odd parity, 1,600 bpi, 9-track, no label tape. Each data file on the tape consists of records containing oil-shale analyses for one well core. The first record in a data file consists of a well-core identifier which is a three-digit number preceded by the character 'C'. The second record contains the well name and location, and the remaining records contain Fischer assay data.
The authors have designed and constructed four types of electron-beam diodes for the new 4-MV RLA injector: a non-immersed foilless diode, a magnetically immersed foilless diode, a foil diode and an ion-focused foilless diode, They are tailored to fit the new injector cavity. The design goals were to produce high quality 10-kA to 20-kA electron beams with a #beta# perpendicular smaller than 0.2 and a beam radius of the order of 2 cm. These beams will be matched to the RLA IFR channel so #beta# perpendicular must be equal to or smaller than the square root of the ratio of the beam current versus Alfven current for f_e = 1. A reentrant anode geometry was selected for the injector cavity design, because it offers substantial savings on the required amount of feromagnetic cores. The inner radius of the outside shell, now only 30 cm, would have been twice as large (60 cm) if a coaxial non-reentrant geometry had been adopted. The shape of the anode ...
This thesis is in the field of gas emission control from automobile and stationary sources. Out of the possible approaches to the elimination of pollutant gases, such as nitrogen oxides (NO{sub x}), one consists in the selective catalytic reduction (SCR) of these NO{sub x} on a suitable heterogeneous catalyst. Ammonia or hydrocarbons are employed as reducing agents. The most important catalysts active in the SCR of NO{sub x} are based on ions of transition metal either supported on several oxides or dispersed in zeolites. The catalysts have been characterized by electron magnetic resonance techniques (EPR, ENDOR, ESEEM) and the interaction of catalysts with nitrogen oxides, with reducing and poisoned agents have been followed with the same techniques. Copper dispersed on alumina and its interaction with both NO and ammonia has been investigated. Also the interaction between both water and ammonia with copper dispersed in zeolite ZSM-5 has been ...
Constitutive activation of the oncogenic transcription factor STAT3 frequently occurs in various human malignancies. STAT3 activation involves dimerization via intermolecular pTyr-SH2 interaction. Thus, antagonizing this interaction is a feasible approach to inhibit STAT3 activation for cancer therapy. In order to identify selective STAT3 inhibitors, we developed a biochemical HTS system based on AlphaScreen technology, which measures the abilities of test compounds to antagonize pTyr-SH2 interactions. We screened our chemical libraries using this system and identified 5,15-diphenylporphyrin (5,15-DPP) as a selective STAT3-SH2 antagonist. Selective inhibition of STAT3 nuclear translocation and DNA biding activity was observed in cells treated with 5,15-DPP. IL-6-dependent dimerization of STAT3, c-myc promoter binding and c-myc protein expression were all suppressed by 5,15-DPP, whereas no decrement in ...
A laboratory model of a TPV generator in the kilowatt range was developed and tested. It was based on methane/oxygen combustion and a spectrally matched selective emitter/collector pair (ytterbia emitter-silicon PV cell). The system demonstrated a power output of 2.4 kilowatts at an overall efficiency of 4.5{percent} without recuperation of heat from the exhaust gases. Key aspects of the effort include: (1) process development and fabrication of mechanically strong selective emitter ceramic textile materials; (2) design of a stirred reactor emitter/burner capable of handling up to 175,000 Btu/hr fuel flows; (3) support to the developer of the production silicon concentrator cells capable of withstanding TPV environments; (4) assessing the apparent temperature exponent of selective emitters; and (5) determining that the remaining generator efficiency improvements are readily defined ...
Fuel cells based on solid oxides ('SOFC') are excellent alternative devices for power generation, when they are operated at high temperature, e.g. above 600 C. Having only fixed parts for the power generating part of the device is only one advantage of the fuel cell. Due to their unique design, these devices offer a maximum of efficiency for energy conversion compared to conventional power generating systems, which are mainly based on turbines. One aim of this thesis is the examination of alternative electrolyte and cathode materials for the SOFC applications at reduced temperatures, which means in the temperature range between 600 C and 750 C. For the first main task, several materials from the oxygen ion conducting electrolytes were selected. Different strontium and magnesium doped lanthanum gallate (LSGM) materials with additional transition metal doping were selected and prepared ...
Background: Cu-diacetyl-bis(N{sup 4}-methylthiosemicarbazone) [Cu-ATSM], although excellent for oncology applications, may not be suitable for delineating cardiovascular or neurological hypoxia. For this reason, new Cu hypoxia positron emission tomography (PET) imaging agents are being examined to search for a higher selectivity for hypoxic or ischemic tissue at higher oxygen concentrations found in these tissues. Two approaches are to increase alkylation or to replace the sulfur atoms with selenium, resulting in the formation of selenosemicarbazones. Methods: Three {sup 64}Cu-labeled selenosemicarbazone complexes were synthesized and one was screened for hypoxia selectivity in vitro using EMT-6 mouse mammary carcinoma cells. Rodent biodistribution and small animal PET images were obtained from BALB/c mice implanted with EMT-6 tumors. One alkylated thiosemicarbazone was synthesized and examined. Results: Of the three ...
We examined whether proton magnetic resonance spectroscopy (MRS) could provide accurate information on histological grade and cell proliferation in astrocytomas. We studied 23 patients with astrocytomas: five grade II, 10 grade III and eight with grade IV (glioblastoma multiforme). We performed proton MRS and determined the Ki-67 labeling index (LI), a tumour proliferation marker, in the same areas of the astrocytomas, and examined the statistical relationship between proton MRS and Ki-67 LI. The N-acetylaspartate (NAA)/creatine-phosphocreatine (Cr) and NAA/choline (Cho)-containing compound ratios were always significantly lower and the Cho/Cr ratios significantly higher than those for normal brain. The Cho/Cr ratio correlated positively and the NAA/Cho ratio inversely with Ki-67 LI. These findings suggest that the Cho signal in proton MRS reflects cellular proliferation. In Kaplan-Meier survival analysis, there was no significant difference ...
Asymmetric plasma divided by the magnetic filter (MF) is numerically simulated by the one-dimensional particle-in-cell code VSIM1D. Depending on the asymmetry, the system behaves static or dynamic. In the static state, the potentials of the main plasma and the sub-plasma are given by the sheath potentials, {phi}{sub M} - 3T{sub Me}/e and {phi}{sub S} - 3T{sub Se}/e, respectively, with e being an electron charge and T{sub Me} and T{sub Se} being electron temperatures (T{sub Me} > T{sub Se}). In the dynamics state, while {phi}{sub M} - 3T{sub Me}/e, {phi}{sub S} oscillates periodically between {phi}{sub S,min} - 3T{sub Se}/e and {phi}{sub S,max} - 3T{sub Me}/e. The ions accelerated by the time varying potential gap get into the sub-plasma and excite the laminar shock waves. This periodic phenomenon can be understood as a limit cycle due to transitions between two bifurcated states of {phi}{sub S,min} and {phi}{sub S,max}. (author)
Central Nervous System (CNS) involvement, whether primary by the Human Immunodeficiency Virus - HIV - itself, or secondary (toxoplasmosis or lymphoma) is remarkably frequent in AIDS, in 40 to 70% of cases, depending upon the author. In order to study the natural history of this illness, a cohort of 25 asymptomatic seropositive patients have been established. Every 6 months these patients undergo biological and clinical examinations, as well as Magnetic Resonance brain scans. After two examinations at a 6 month's interval, the first results are reported. Out of these 25 cases, 9 present anomalies: One patient with diffuse cerebral atrophy and 8 others with high signal intensity areas on T2 weighted sequences, like those of the Multiple Sclerosis. No relationship could be demonstrated between the existence of these lesions and various criteria such as age, sex, risk factors and T4 cells count. The nature of these lesions is not lear. They ...
This article describes the nature of the electromagnetic waves, what they are and how do they affect us. Current concern is focused on exposure to low level power-frequency magnetic fields like microwave radiation from mobile phones and leaking microwave ovens; high power radiation from defence and airport radars; fields close to high voltage transmission lines; radio frequency fields from industrial welders and heaters and DC magnetic fields in aluminium smelters. These fields with frequency less than 300 GHz do not carry sufficient energy to break chemical bonds and it is assumed that they cannot damage cell DNA. The amount of radiation absorbed by a human exposed to far field electromagnetic radiation (EMR) depends on the orientation and size of the person. In the 30-300 MHz range it is possible to excite resonance in the whole or partial body such as the head. It is emphasised that since there are some evidence that ...
Crystals of a new ternary samarium rhenium oxide, Sm{sub 3}ReO{sub 7} were obtained by subsolidus reaction of samariumsesquioxide and rheniumdioxide (ratio 1.5:1) in sealed Pt-10Rh-tubes at 1673 K. The structure was determined by single-crystal X-ray diffraction. Sm{sub 3}ReO{sub 7} crystallizes in the orthorohombic system with unit cell dimensions a = 10.736(5), b = 7.392(3), and c = 7.519(3) in space group Cmcm (No. 63) with Z = 4. The structure consists of ReO{sub 6} octahedra, distorted SmO{sub 6} octahedra, and SmO{sub 8} prisms that are interconnected to each other to form a three-dimensional network. Rhenium has the formal oxidation state of +5 but no metal-metal bond is observed in this compound. The observed magnetization in the temperature range 4 K < T < 52 K is explained by a Curie-Weiss law modified by a temperature independent Van Vleck paramagnetism of samarium (3+).
Nuclear magnetic resonance is a powerful technique that can be used in a wide range of applications, such as the structural characterization of high molecular weight molecules, conformational studies on enzymes in solution, enzyme-substrate or DNA-protein interactions, monitoring of cell metabolism in vivo, and for diagnostic purposes, employing spectroscopic and imaging techniques. This course was organized in order to introduce the participants to the fundamentals of NMR spectroscopy, and offer practical advice on performing NMR experiments on cell systems, cell and tissue extracts and animal models. The main implications regarding human experiments were also discussed. Finally the quantification of information and the interpretation of data were considered with regard to the main nuclei observed. [Italiano] La risonanza magnetica nucleare e` una delle tecniche spettroscopiche che meglio risponde ...
We studied whether plasma-etching techniques can use standard screen-printed gridlines as etch masks to form self-aligned, patterned-emitter profiles on multicrystalline-silicon (mc-Si) cells from Solarex. We conducted an investigation of plasma deposition and etching processes on full-size mc-Si cells processed in commercial production lines, so that any improvements obtained would be immediately relevant to the PV industry. This investigation determined that reactive ion etching (RIE) is compatible with using standard, commercial, screen-printed gridlines as etch masks to form self-aligned, selectively doped emitter profiles. This process results in reduced gridline contact resistance when followed by plasma-enhanced chemical vapor deposition (PECVD) treatments, an undamaged emitter surface easily passivated by plasma-nitride, and a less heavily doped emitter between gridlines for reduced emitter recombination. This ...
Gold and silver nanoparticles display extraordinarily large apparent refractive indices near their plasmon resonance (PR) wavelengths. These nanoparticles show good contrast in a narrow spectral band but are poorly resolved at other wavelengths in differential interference contrast (DIC) microscopy. The wavelength dependence of DIC contrast of gold/silver nanoparticles is interpreted in terms of Mie's theory and DIC working principles. We further exploit this wavelength dependence by modifying a DIC microscope to enable simultaneous imaging at two wavelengths. We demonstrate that gold/silver nanoparticles immobilized on the same glass slides through hybridization can be differentiated and imaged separately. High-contrast, video-rate images of living cells can be recorded both with and without illuminating the gold nanoparticle probes, providing definitive probe identification. Dual-wavelength DIC microscopy thus presents a new approach to the simultaneous ...
Lectin is a generic name of sugar binding protein in living organisms. With an objective to clarify physiological functions of lectin in marine invertebrates and utilize it as a useful material in the bio-chemical industry, studies were carried out on the chemical structure, distribution in living organisms and structural changes of lectin. Lectin is involved with such physiological actions as immunity reactions, generation and differentiation, Ca fixation and symbiosis. Lectin is one of the main components of lymph fluid in shellfish and crustacean, and is a multi-functional polymer that is related with foreign substance recognition, Ca transport, and shell formation. Lectin of a certain kind shows strong actions to accelerate cell division. Organs and cells were cultivated for lectin producing organs and lectin producing cells to verify the production thereof. Elucidation was attempted in a molecular level on such ...
Using a coplanar, end-mounted antenna as a baseline, various configuration trades were performed to select a preferred solid state concept. The increase in efficiency that could be realized by use of multi bandgap solar cells, either with klystron or solid state antenna was evaluated. Satellite configurations were developed to exploit the sandwich antenna concept wherein solar cells are located on one side of the antenna panel and solid state dc/RF converters on the other side. These concepts entailed various primary and secondary reflector arrangements for directing solar energy to the solar cell side of the antenna with higher concentration ratios than used on the coplanar configurations. Operations analysis included development of a satellite construction scenario, a concept for the SCB, a top-level satellite construction operation, construction operation, construction timelines and crew sizes, mass ...
Prognosis of 95 consecutive patients with non-small cell lung cancer with brain metastases were evaluated. Three factors, therapy for brain metastases, general performance status (PS) and distant metastases to other organs had significant impact on survival. Among these 3 factors, PS was independent from the other 2 factors. Significant correlation was present, however, between therapy and other organ metastases, and few patients with brain and other distant metastases received aggressive treatment for brain metastases. Cranial irradiation had significant impact on survival even in those patients with brain and other distant metastases. Cranial irradiation also reduced death from brain metastases in responders. Our results indicate that there are several subgroups with different prognosis in patients with non-small cell lung cancer with brain metastases, therefore the most beneficial treatment modality should be selected ...
Protonic ceramic membrane fuel cells (PCMFCs) based on proton-conducting electrolytes have attracted much attention because of many advantages, such as low activation energy and high energy efficiency. A stable, easily sintered perovskite oxide BaCe_0_._5Zr_0_._3Y_0_._1_6Zn_0_._0_4O_3_-_#delta# (BCZYZ) as electrolyte for proton-conducting solid oxide fuel cells (SOFCs) with Sm_0_._5Sr_0_._5CoO_3_-_#delta# (SSC) composite cathode is investigated. By fabricating thin membrane BCZYZ electrolyte (#approx#20 #mu#m) synthesized by a modified Pechini method on NiO-BCZYZ anode support, PCMFCs are assembled and tested by selecting SSC perovskite cathode with high mixed ionic and electronic conductivities. An open-circuit potential of 1.015 V, a maximal power density of 528 mW cm"-"2, and a low polarization resistance of the electrodes of 0.15 #OMEGA# cm"2 is achieved at 700 "oC. The results indicate that BCZYZ proton-conducting ...
Full text: The general population is daily exposed to chronic, low doses of ionizing radiation (IR) from both natural and artificial sources. The biological consequences of acute, high dose IR exposure can be readily determined; however, the nature and significance of low dose, low dose-rate IR effects are still the subject of debate. Confounding the issue, are the phenomena collectively referred to as the Radiation-induced Bystander Effect (RIBE). The RIBE describes a collection of in vitro observations that suggest the presence of a soluble, transmissible factor(s) released from irradiated cells that can induce a biological response in un-irradiated cells. The induction, nature and magnitude of the RIBE varies between cell culture systems, radiation sources and end-points measured. Efforts to confirm the presence of the RIBE in vivo have been confined to in vivo-like culture systems and limited work with tumour and ...
Microorganisms associated with fractured basalt core were compared to those suspended in groundwater pumped from the same well in the eastern Snake River Plain Aquifer (Idaho, USA). Two wells influenced to different degrees by a mixed-waste plume in the fractured basalt aquifer were examined. In one well, an array of dialysis cells filled with either deionized water or crushed basalt was equilibrated to compare the microorganisms collected in this fashion with those from core and groundwater samples collected in a traditional manner from the same well. Analyses were performed to characterize these samples and to provide a basis for comparison. These included total cell counts by microscopy; total biomass by phospholipid fatty acid analysis; enumerations of viable aerobic heterotrophs, groups of putative aerobic co-metabolic TCE-degraders and aerobic H2-oxidizing bacteria; mineralization of 14C- labeled acetate; and enrichments for dissimilatory ...
Sodium-ion-conducting glasses are considered a promising alternative to the ceramic electrolytes. The glass upon which the most development work has been done is a sodium borate glass, which has an ionic resistivity of about 2 x 10/sup 4/ #OMEGA#-cm at 300"0C. Because of its high resistivity, cells using this borate glass require thousands of hollow glass fibers, each about 80 micrometers outer diameter (15 micrometer wall). In spite of its greater complexity, the cell with the glass electrolyte is of interest because of its potential for lower cost and higher power than the cell with ceramic electrolyte. Recently, silicate glasses of lower resistivity have been proposed for this application. These include: a soda-alumina-silica glass (900 #OMEGA#-cm at 300"0C), a soda-zirconia-magnesia-silica glass (700 #OMEGA#-cm at 300"0C), and a soda-zirconia-silica glass (600 #OMEGA#-cm at 300"0C). These lower resistivity glasses would ...
BackgroundDespite an ever-improving understanding of the molecular biology of cancer, the treatment of most cancers has not changed dramatically in the past three decades and drugs that do not discriminate between tumor cells and normal tissues remain the mainstays of anticancer therapy. Since Hsp90 is typically involved in cell proliferation and survival, this is thought to play a key role in cancer, and Hsp90 has attracted considerable interest in recent years as a potential therapeutic target.MethodsWe focused on the interaction of Hsp90 with its cofactor protein p60/Hop, and engineered a cell-permeable peptidomimetic, termed "hybrid Antp-TPR peptide", modeled on the binding interface between the molecular chaperone Hsp90 and the TPR2A domain of Hop.ResultsIt was demonstrated that this designed hybrid Antp-TPR peptide inhibited the interaction of Hsp90 with the TPR2A domain, inducing cell death of ...
This paper addresses the stability aspects of several successful dc superconducting magnets such as large bubble chamber magnets, and magnets for the Mirror Fusion Test Facility and MHD Research Facility. Specifically, it will cover Argonne National Laboratory 12-Foot Bubble Chamber magnets, the 15-foot Bubble Chamber magnets at Fermi National Laboratory, the MFTF-B Magnet System at Lawrence Livermore National Laboratory, the U-25B Bypass MHD Magnet, and the CFFF Superconducting MHD magnet built by Argonne National Laboratory. All of these magnets are cooled in pool-boiling mode. Magnet design is briefly reviewed. Discussed in detail are the adopted stability critera, analyses of stability and disturbance, stability simulation, and the final results of magnet ...
We investigate the magnetic braking of the core of an axisymmetric cloud whose rotation axis is parallel to the mean direction of the magnetic field. (author).
Checks are performed on the alignment of the magnets in the LHC tunnel. It is vital that each magnet is placed exactly where it has been designed so that the path of the beam is precisely controlled.
The FLAPW (full-potential linearized-augmented plane-wave) method is one of the most accurate first-principles methods for determining electronic and magnetic properties of crystals and surfaces. Until the present work, the FLAPW method has been limited to systems of less than about one hundred atoms due to a lack of an efficient parallel implementation to exploit the power and memory of parallel computers. In this work we present an efficient parallelization of the method by division among the processors of the plane-wave components for each state. The code is also optimized for RISC (reduced instruction set computer) architectures, such as those found on most parallel computers, making full use of BLAS (basic linear algebra subprograms) wherever possible. Scaling results are presented for systems of up to 686 silicon atoms and 343 palladium atoms per unit cell, running on up to 512 processors on a CRAY T3E parallel computer.
Positron emission tomography (PET) is the gold standard for non-invasive assessment of myocardial viability and allows accurate detection of coronary artery disease by assessment of myocardial perfusion. Magnetic resonance imaging (MRI) provides high resolution anatomical images that allow accurate evaluation of ventricular structure and function together with detection of myocardial infarction. Potential hybrid PET/MR tomography may potentially facilitate the combination of information from these imaging modalities in cardiology. Furthermore, the combination of anatomical MRI images with the high sensitivity of PET for detecting molecular targets may extent the application of these modalities to the characterization of atherosclerotic plaques and to the evaluation of angiogenetic or stem cell therapies, for example. This article reviews studies using MRI and PET in parallel to compare their performance in cardiac applications together with the ...
Cerium L_3 XANES (x-ray-absorption near-edge-structure) spectra were analyzed to separate Ce moment contributions and mixed valence (MV) in complex magnetic silicides CePd_2_-_xMn_xSi_2 (0#<=#x#<=#2). The Ce valence mixing does not vary linearly with x, but increases rapidly for x#>=#1.5. The associated moment collapse correlates with pronounced deviations of the unit-cell volume from Vegard law and the onset of structural instability. Reorientation of [001] Mn 3d antiferromagnetic order for x<2 appears to rapidly suppress the weak Ce valence mixing coexisting with antiferromagnetic order in CeMn_2Si_2.
Course website from Cambridge on ceramic materials. This site contains eight lectures in PDF format (Adobe Reader required), two question sheets, five practicals (including answers), digital movies and further useful links. "There is a strong relationship between the structure of a material and its physical properties. The properties of a material whether mechanical, electrical, optical or magnetic, determine how it can be used in practical applications. In this course, the focus is on the structure / property relationship for ionic materials with electrical properties utilised in various transducer devices. The materials considered include perovskites, which have special polarisation properties exploited in ferroelectric, pyroelectric and piezoelectric devices. Other oxides, such as zirconia, have structures permitting rapid diffusion of ions, making them suitable for use in sensors, fuel cells and batteries. The scientific principles ...
The magnetic fluid is a colloidal suspension of magnetite in kerosene, prepared by a low-cost process. Separation is accomplished in an open trough filled with magnetic fluid. A magnetic field is established in the fluid, by energizing an electromagnet having poles on each side of the trough. Due to the design of the magnet poles and air gaps, the magnetic field is strongest at the bottom, about 10,000 oersteds, and uniformly decreases in strength to about 2000 oersteds at the top of the fluid. Therefore, the magnetic field gradient increases with depth. The magnetic force attracts the entire separation medium (magnetic fluid) creating a reaction force of equal magnitude and acting in the opposite direction. This reaction created within a magnetic fluid/magnetic field combination ...
The liquid-phase synthesis of metal oxide nanoparticles in organic solvents under exclusion of water is nowadays a well-established alternative to aqueous sol-gel chemistry. In this article, we highlight some of the advantages of these routes based on selected examples. The first part reviews some recent developments in the synthesis of ternary metal oxide nanoparticles by surfactant-free nonaqueous sol-gel routes, followed by the discussion of the morphology-controlled synthesis of lanthanum hydroxide nanoparticles, and the presentation of structural peculiarities of manganese oxide nanoparticles with an ordered Mn vacancy superstructure. These examples show that nonaqueous systems, on the one hand, allow the preparation of compositionally complex oxides, and, on the other hand, make use of the organic components (initially present or formed in situ) in the reaction mixture to tailor the morphology. Furthermore, obviously even the crystal structure can differ from ...
In the self-cooling blankets of the Tokamak fusion reactor, a liquid metal, namely liquid lithium, is pumped through a system of ducts to transfer heat and capture neutrons. One of the blanket designs proposed in Argonne National Laboratory's Blanket Comparison and Selection study uses a combination of poloidal and toroidal ducts in order to maximize heat transfer while minimizing net pressure drop. In the design, the poloidal and toroidal ducts meet at sharp, abrupt corners. They were modelled as two identical, straight, semi-infinite, thin-walled, rectangular ducts with 45{degree} miters and joined at a 90{degree} angle in the plane of a strong, uniform magnetic field. While in the toroidal containment vessel (i.e. the blanket), the liquid lithium is subjected to a large electromagnetic body force due to the presence of a strong magnetic field. This body force so dominates the flow as to make the inertial and ...
The effect of the external pH on the intracellular pH in mung bean (Vigna mungo (L.) Hepper) root-tip cells was investigated with the "3"1P nuclear magnetic resonance (NMR) method. The "3"1P NMR spectra showed three peaks caused by cytoplasmic G-6-P, cytoplasmic Psub(i) and vacuolar Psub(i). The cytoplasmic and vacuolar pHs could be determined by comparing the Psub(i) chemical shifts with the titration curve. When the external pH was changed over a range from pH 3 to 10, the cytoplasmic pH showed smaller changes than the vacuolar pH, suggesting that the former is regulated more strictly than the latter. The H"+-ATPase inhibitor, DCCD, caused the breakdown of the mechanism that regulates the intracellular pH. H"+-ATPase appears to have an important part in the regulation of the intracellular pH. (author).
The aim of this work is to understand the reasons for the selectivity shown in the complexation by unsaturated heteropolyanions (HPA) of actinides (An) which are oxidized to the number +IV. Different studies have been carried out, both in solution and in solid state, on P_2W_1_7O_6_1"1"0"- and its complexes with Zn"2"+, UO_2"2"+, Ce"4"+, Th"4"+ and U"4"+ to characterize the nature of the complexation site offered to the cation. Among the actinides(IV), the U"4"+ ion has been selected due to its singular spectroscopic and magnetic properties. An initial series of studies, in solution, using NMR"3"1P has thus enabled us to characterize these complexes and to compare them to those formed with the complexing agent PW_1_1O_3_9"8"-. This body of data allows to identify an identical complexation site for both ligands. An analysis of the NMR"3"1P spectrum of U(P_2W_1_7O_6_1)_2"1"6"- has shown a plane of symmetry passing through the ...
Rare Earth Cobalt (REC) permanent magnets have unique properties that permit solutions to some optical tasks that cannot be accomplished with conventional magnets. A review of design and of performance characteristics of these magnets includes an analytical description of the three dimensional fringe fields of REC quadrupoles.
The steroidogenic factor 1 (SF-1, also known as NR5A1) is a transcription factor belonging to the nuclear receptor superfamily. Whereas most of the members of this family have been extensively characterized, the therapeutic potential and pharmacology of SF-1 still remains elusive. Described here is the identification and characterization of selective inhibitory chemical probes of SF-1 by a rational ultra-high-throughput screening (uHTS) strategy. A set of 64,908 compounds from the National Institute of Health's Molecular Libraries Small Molecule Repository was screened in a transactivation cell-based assay employing a chimeric SF-1 construct. Two analogous isoquinolinones, ethyl 2-[2-[2-(2,3-dihydro-1,4-benzodioxin-7-ylamino)-2-oxoethyl]-1-oxoisoquinolin-5-yl]oxypropanoate (SID7969543) and ethyl 2-[2-[2-(1,3-benzodioxol-5-ylmethylamino)-2-oxoethyl]-1-oxoisoquinolin-5-yl]oxypropanoate and (SID7970631), were identified as potent submicromolar ...
... in the design of such devices as fusion reactors, magnetohydrodynamic generators, magnetically levitated vehicles, magnetic forming devices, and ...
The concept of a direct energy recovery system that applies a varying magnetic field is proposed for a negative-ion-based neutral beam injection system (NNB) to heat a plasma and/or drive a plasma current in a fusion reactor. The output beam energy and power of such an NNB will be {approximately}1 MeV and {approximately}1- MW/beam-line, respectively, and nearly the same amounts of positive- and negative-ion beams remain unneutralized in an NNB by using a gas-neutralizing cell. Therefore, the output of a beam direct convertor in an NNB is a bipolar direct current (dc) electric power with close to {plus_minus} 1 MV and several amperes if a conventional electrostatic or magnetostatic field is applied for ion beam separation. However, such high-voltage dc power is difficult to handle at the point of the regeneration of the power back to a commercial electric line because a very high voltage inverter tough enough to withstand occasional sparkdowns ...
This paper traces the development and progress of magnetic suspension systems and magnetic bearings in the USSR. The paper describes magnetic bearings for turbomachines, magnetic suspension systems for vibration isolation, some special measuring devices, wind tunnels, and other applications. The design, principles of operation, and dynamic characteristics of the system are presented.
In order to examine the state of technology of all areas of magnetic suspension and to review related recent developments in sensors and controls approaches, superconducting magnet technology, and design/implementation practices, a symposium was held. The proceedings are presented. The sessions covered the areas of bearings, sensors and controls, microgravity and vibration isolation, superconductivity, manufacturing applications, wind tunnel magnetic suspension systems, magnetically levitated trains (MAGLEV), space applications, and large gap magnetic suspension systems.
Purpose: Photodynamic therapy (PDT) is based on the interaction of a photosensitizing (PS) agent, light, and oxygen. Few new PS agents are being developed to the in vivo stage, partly because of the difficulty in finding the right treatment conditions. Response surface methodology, an empirical modeling approach based on data resulting from a set of designed experiments, was suggested as a rational solution with which to select in vivo PDT conditions by using a new peptide-conjugated PS targeting agent, neuropilin-1. Methods and Materials: A Doehlert experimental design was selected to model effects and interactions of the PS dose, fluence, and fluence rate on the growth of U87 human malignant glioma cell xenografts in nude mice, using a fixed drug-light interval. All experimental results were computed by Nemrod-W software and Matlab. Results: Intrinsic diameter growth rate, a tumor growth parameter independent of the ...
The detection of rare mutations has many important applications, including risk assessment of drugs and chemicals, measuring environmental exposures to genotoxins, and cancer cell detection. A sensitive genotypic selection method has been developed that combines two different mutant allele selection techniques, MutEx enrichment and allele-specific competitive blocker PCR (ACB-PCR). This method was developed and evaluated for the detection of a CAA --> AAA mutation at codon 61 of the mouse H-ras gene. The MutEx enrichment is based on MutS binding to a mismatched basepair in heteroduplex DNA. The bound MutS protects the mutant allele from degradation during subsequent exonuclease treatment. ACB-PCR preferentially amplifies a mutant allele in a PCR reaction using a primer that has more mismatches to the wild-type allele than the mutant allele. By combining these two approaches, the codon 61 mutation was detected at mutant ...
Thin film solar cells and solar cell testing - photovoltaic cells, radiation damage to cadmium sulfide solar cells, and airplane testing of solar cells
Abstract The term -stem cell- most commonly refers to embryonic stem cells, particularly in the lay media; however, it also describes other cell types. A stem cell represents a cell of multi-lineage potential with the ability for self-renewal. It is now clear that the plasticity and immortality of a given stem cell will depend on what type of stem cell it is, whether an embryonic stem cell, a fetal-placental stem cell or an adult stem cell. Stem cells offer great promise as cell-based therapies for the future. With evolving technology, much of the socio-political debate regarding stem cells can now be avoided.
A non-contact method, using magnetic drag force principle, was proposed to design the braking systems to improve the shortcomings of the conventional braking systems. The extensive literature detailing all aspects of the magnetic braking is briefly reviewed, however little of this refers specifically to upright magnetic braking system, which is useful for industries. One of the major issues to design upright magnetic system is to find out the magnetic flux. The changing magnetic flux induces eddy currents in the conductor. These currents dissipate energy in the conductor and generate drag force to slow down the motion. Therefore, a finite element model is developed to analyze the phenomena of magnetic flux density when air gap and materials of track are varied. The verification shows the predicted magnetic flux is within ...
Short synthetic single-stranded oligodeoxyribonucleotides (ssODNs) can be used to introduce subtle modifications into the genome of mouse embryonic stem cells (ESCs). We have previously shown that effective application of ssODN-mediated gene targeting in ESC requires (transient) suppression of DNA mismatch repair (MMR). However, whereas transient down-regulation of the mismatch recognition protein MSH2 allowed substitution of 3 or 4 nucleotides, 1 or 2 nucleotide substitutions were still suppressed. We now demonstrate that single- or dinucleotide substitution can effectively be achieved by transient down-regulation of the downstream MMR protein MLH1. By exploiting highly specific real-time PCR, we demonstrate the feasibility of substituting a single basepair in a non-selectable gene. Howev...
The dimercaptosuccinic acid metronidazole ester (DMSAMe) was synthesized and radiolabeled with 99mTc to form the 99mTc-DMSAMe complex in high yield. The radiochemical purity of the 99mTc-DMSAMe complex was over 90%, as measured by TLC and by HPLC, without any notable decomposition at room temperature over a period of 6?h. Its partition coefficient indicated that it was a lipophilic complex. The tumor cell experiment and the biodistribution in mice bearing S 180 tumor showed that the 99mTc-DMSAMe complex had a certain hypoxic selectivity and accumulated in the tumor with high uptake and good retention. The tumor/blood and tumor/muscle ratios increased with time, suggesting it would be a possible tumor hypoxia imaging agent.
Classical methods for the study of complex fluid phase behavior include static and dynamic equilibrium cells that usually require vapor and liquid recirculation. These are sophisticated, costly apparatus that require highly trained operators, usually months of labor-intensive work per mixture, and the data analysis is also rather complex. Simpler approaches to the fundamental study of azeotropes are highly desirable, even if they provide only selected cuts through the phase diagram. Recently, we introduced an advanced distillation curve measurement method featuring: (1) a composition explicit data channel for each distillate fraction (for both qualitative and quantitative analysis), (2) temperature measurements that are true thermodynamic state points that can be modeled with an equation o...
A solar thermophotovoltaic (STPV) system has both terrestrial and space applications because thermal energy storage can be utilized. Excellent properties (heat of fusion=1800 j/gm and melting temperature=1680 K) make silicon the ideal thermal storage material for an STPV system. Using a one dimensional model with tapering of the silicon storage material, it was found that several hours of running time with modest lengths ({approximately}15 cm) of silicon are possible. Calculated steady-state efficiencies for an STPV system using an Er-YAG selective emitter and ideal photovoltaic (PV) cell model are in the range of 15{percent}{endash}17{percent}. Increasing the taper of the storage material improves both efficiency and power output. {copyright} {ital 1996 American Institute of Physics.}
Modifications to the reference concept were studied and the best approaches defined. The impact of the high efficiency multibandgap solar array on the reference concept design is considered. System trade studies for several solid state concepts, including the sandwich concept and a separate antenna/solar concept, are described. Two solid state concepts were selected and a design definition is presented for each. Magnetrons as an alternative to the reference klystrons for dc/rf conversion are evaluated. System definitions are presented for the preferred klystron and solid state concepts. Supporting systems are analyzed, with major analysis in the microwave, structures, and power distribution areas. Results of studies for thermal control, attitude control, stationkeeping, and details of a multibandgap solar cell study are included. Advanced laser concepts and the meteorological effects of a laser beam power transmission concept are considered.
Purpose PR-104, a bioreductive prodrug in clinical trial, is a phosphate ester which is rapidly metabolized to the corresponding alcohol PR-104A. This dinitrobenzamide mustard is activated by reduction to hydroxylamine (PR-104H) and amine (PR-104M) metabolites selectively in hypoxic cells, and also independently of hypoxia by aldo-keto reductase (AKR) 1C3 in some tumors. Here, we evaluate reductive metabolism of PR-104A in mice and its significance for host toxicity. Methods The pharmacokinetics of PR-104, PR-104A and its reduced metabolites were investigated in plasma and tissues of mice (with and without SiHa or H460 tumor xenografts) and effects of potential oxidoreductase inhibitors were evaluated. Results Pharmacokinetic studies identified extensive non-tumor reduction of PR-104A to t...
Membranes in Palladium and its alloys, in particular Pd/Ag alloys, are selectively permeable to hydrogen and can therefore be used to purify hydrogen. It is intended to use them as material for electrodes in fuel cells. As the manufacturing process of a substrate Pd/Ag-layer consists of several stages and is still not completely understood, it would be advantageous to be able to characterise separately the layers of noble metals obtained by electro-plating . Attempts are being made in this work to vary the cristallographical structure of the deposited alloy by the choice of test parameters and by sintering when depositing the Pd/Ag. The layers produced are to be examined using an interference microscope and X-ray diffraction. Moreover, the diffusion behaviour of the hydrogen is to be examined with an electro-chemical pulse method specifically developed for this purpose. figs., tabs., 27 refs.
This work reports phase equilibrium measurements for the ternary systems linoleic (acid+CO2+ethanol) and (linolenic acid+CO2+ethanol). The fatty acids present in the ternary systems were selected based on composition of banana peel oil extracted by supercritical CO2 at 20MPa and 313K. The motivation of this research relies on the fact that these unsaturated fatty acids are recognized to play an important role in lowering blood pressure and serum cholesterol and because they are present in high concentrations in banana peel extract. Besides that, equilibrium data of these compounds are scarce in literature. The phase equilibrium experiments were performed using a high-pressure variable-volume view cell over the temperature range of (303 to 343)K and pressures up to 19MPa. For both systems, ...
Abstract Preparation of antibacterial alginate films incorporating extruded white ginseng (EWG) extracts was attempted. The antibacterial effect of EWG extract on six selected food pathogenic bacteria was compared with the effect of red ginseng (RG) and white ginseng (WG) extracts. The EWG was processed in a twin-screw extruder with feed moisture of 20% and barrel temperature of 115 and 130C. The data obtained by agar diffusion assay demonstrated that the film containing 1-g/mL of EWG at barrel temperatures of 115 (EWG-115) and 130C (EWG-130) exhibited stronger antibacterial activity against the four strains of bacteria than the other extracts RG and WG. All films sampled showed reduction in bacteria cell counts (log cycle) compared with the control. After 24-h of incubation, Pseudomonas a...
Health risks associated with inhalation of mineral dusts have been identified to a great extent through epidemiology studies, but also have been assessed by conducting subchronic and chronic inhalation studies typically on rodents. However, in vivo studies are softly, time-consuming, requiring complex technologies, and may not yield information on cellular and molecular mechanisms of response. As a result, the use of in vitro cell culture systems has played an important role in studying the toxicology of mineral dusts and providing insight into action mechanisms. This article reviews selected in vitro approaches that are used to investigate the cytotoxic and inflammatory properties of mineral particles and fibers. In addition key findings as they relate to understanding the toxicology of mineral dusts are presented. 165 refs., 1 fig., 5 tab.
Abstract In the 1990s, significant efforts were invested in the research and development of food-grade expression systems in lactic acid bacteria (LAB). At this time, Lactococcus lactis in particular was demonstrated to be an ideal cell factory for the food-grade production of recombinant proteins. Steady progress has since been made in research on LAB, including Lactococcus, Lactobacillus and Streptococcus, in the areas of recombinant enzyme production, industrial food fermentation, and gene and metabolic pathway regulation. Over the past decade, this work has also led to new approaches on chromosomal integration vectors and host/vector systems. These newly constructed food-grade gene expression systems were designed with specific attention to self-cloning strategies, food-grade selection...
Three in vivo assays were used to measure the immunocompetence of chickens in two generations of a selection experiment. The obtained data were used to estimate the variance components for sire and dam for antibody production to Pasteurella multocida and Mycoplasma gallisepticum vaccines, for T-cell-mediated immunity evaluated by a phytohemagglutinin wing web assay, and for clearance of foreign particles from the circulatory system. Heritabilities of and genetic correlations among these immunological traits were calculated from the sire variance components. Heritability estimates of the immunological traits based on the sire component of variance ranged from .06 to .53, and genetic correlations among immunological traits were generally negative. PMID:1956847
A composition and method for encapsulating a photovoltaic device which minimizes discoloration of the encapsulant. The composition includes an ethylene-vinyl acetate encapsulant, a curing agent, an optional ultraviolet light stabilizer, and/or an optional antioxidant. The curing agent is preferably 1,1-di-(t-butylperoxy)-3,3,5-trimethylcyclohexane; the ultraviolet light stabilizer is bis-(N-octyloxy-tetramethyl) piperidinyl sebacate and the antioxidant is selected from the group consisting of tris (2,4-di-tert-butylphenyl) phosphite, tetrakis methylene (3,5-di-tert-butyl-4-hydroxyhydrocinnamate) methane, octadecyl 3,5-di-tert-butyl-4-hydroxyhydrocinnamate, and 2,2'-ethylidene bis(4,6-di-t-butylphenyl) fluorophosponite. The composition is applied to a solar cell then cured. The cured product contains a minimal concentration of curing-generated chromophores and resists UV-induced degradation.
The absorption of carbonyl sulfide in aqueous methyldiethanolamine (MDEA) was studied over a range of temperatures and MDEA concentrations. MDEA is commonly used for selective absorption of hydrogen sulfide in the presence of carbon dioxide. However, sulfur in the form of COS may also be present and it is necessary that estimates of absorption rates of this compound be made. The objective of this study is to determine the physiochemical properties needed to predict COS absorption rates in aqueous MDEA. Free gas solubility and the diffusivity of COS in MDEA solutions were measured over the temperature range 15 to 40{sup 0}C for MDEA concentrations up to 30 weight per cent using the nitrous oxide analogy method. Solubilities were measured volumetrically in an equilibrium cell and diffusivities were measured using a laminar liquid jet absorber. The kinetics of the reaction between COS and MDEA were studied by measuring absorption rates in a single ...
This study sought to quantitate lidocaine's interaction with alpha-1-acid glycoprotein (AAG), human serum albumin (HSA), and AAG in the presence of HSA, and to determine the extent of displacement of lidocaine from its binding site(s) by selected cardiovascular drugs (dipyridamole, disopyramide and quinidine). Since the limited experimental work reported in this area has involved the use of a single lidocaine concentration, this study involved the evaluation of a range of lidocaine concentrations. Lidocaine interaction with plasma proteins (AAG and HSA) was studied at 37/sup 0/C using an isothermal equilibrium dialysis system and /sup 14/C-lidocaine HCl. A dialysis membrane (M.W. cutoff 12,000 to 14,000) separated the two chambers of each dialysis cell. The extent of /sup 14/C-lidocaine dialysis was studied with respect to both drug and protein concentrations. Aliquots of each chamber of each of the cells were ...
A metallization scheme has been developed which allows selective plating of silicon solar cell surfaces. The system is comprised of three layers. Palladium, through the formation of palladium silicide at 300/sup 0/C in nitrogen, makes ohmic contact to the silicon surface. Nickel, plated on top of the palladium silicide layer, forms a solderable interface. Lead-tin solder on the nickel provides conductivity and allows a convenient means for interconnection of cells. To apply this metallization, three chemical plating baths are employed. Palladium is deposited with an immersion palladium solution and an electroless palladium solution, and nickel is deposited with an electroless nickel solution. Solder is applied with a molten solder dip. Extensive development work has been performed to achieve an effective immersion palladium solution formulation, leading to reproducible formation of the palladium silicide contact layer. This ...
Ten patients with suspected islet cell tumors (seven with possible gastrinomas, three with insulinomas) underwent diagnostic evaluation with dynamic CT scanning, routine CT scanning, angiography, and sonography. Venous sampling was also performed in selected instances. Nine sites of gastrinoma and three insulinomas were confirmed surgically in eight patients. Two patients had negative surgical explorations. Routine CT demonstrated five of the nine gastrinomas and one of two insulinomas. Angiography was positive in six of nine gastrinomas and all three insulinomas. Sonography showed only two of the nine gastrinomas and two of the three insulinomas. Dynamic CT scanning demonstrated three additional lesions (two gastrinomas, on insulinoma) not visible on routine CT scanning. Although most of these lesions were visible arteriographically, dynamic CT scans at the appropriate level localized the pathology in the transverse plane and greatly aided in ...
The K0.5 for intracellular sodium of the two forms of (Na ,K )-ATPase which exist in rat adipocytes has been determined by incubating the cells in the absence of potassium in buffers of varying sodium concentration; these conditions shut off the Na pump and allow sodium to equilibrate into the cell. The activity of (Na ,K )-ATPase was then monitored with YWRb /K pumping which was initiated by adding isotope and KCl to 5 mM, followed by a 3-min uptake period. Atomic absorption and SSNa tracer equilibration were used to determine the actual intracellular (Na ) under the different conditions. The K0.5 values thus obtained were 17 mM for alpha and 52 mM for alpha(+). Insulin treatment of rat adipocytes had no effect on the intracellular (Na+) nor on the Vmax of YWRb /K pumping, but did produce a shift in the sodium ion K0.5 values to 14 mM for alpha and 33 mM for alpha(+). This change in affinity can explain the selective ...
Large-scale field tracer experiments have been conducted on Ulchin and Wolsung nuclear sites for the purpose of validating FADAS and of analyzing the environmental characteristics around the nuclear site. The most influential factor in atmospheric dispersion is the meteorological condition. During the experiment, meteorological data were measured on the release point and the selected positions among sampling points. Once radioactive materials are released to the atmosphere, members of public may be exposed through the environmental media such as air, soil and foods. Therefore, to protect the public, adequate countermeasures should be taken at due time for those exposure pathways. Both processes of justification and optimization are applied to a countermeasure simultaneously for decision-making. The work scope of biological research for the radiation protection had contained the search of biological microanalytic methods for the assessment of health effect by ...
The purpose of this text is to train engineers and technologists not just to understand corrosion but to control it. Materials selection, coatings, chemical inhibitors, cathodic and anodic protection, and equipment design are covered in separate chapters. High-temperature oxidation is discussed in the final two chapters ne on oxidation theory and one on controlling oxidation by alloying and with coatings. This book treats corrosion and high-temperature oxidation separately. Corrosion is divided into three groups: (1) chemical dissolution including uniform attack, (2) electrochemical corrosion from either metallurgical or environmental cells, and (3) stress-assisted corrosion. Corrosion is logically grouped according to mechanisms rather than arbitrarily separated into different types of corrosion as if they were unrelated. For those university students and industry personnel who approach corrosion theory very hesitantly, this text will present ...
The purpose of this text is to train engineers and technologists not just to understand corrosion but to control it. Materials selection, coatings, chemical inhibitors, cathodic and anodic protection, and equipment design are covered in separate chapters. High-temperature oxidation is discussed in the final two chapters ne on oxidation theory and one on controlling oxidation by alloying and with coatings. This book treats corrosion and high-temperature oxidation separately. Corrosion is divided into three groups: (1) chemical dissolution including uniform attack, (2) electrochemical corrosion from either metallurgical or environmental cells, and (3) stress-assisted corrosion. Corrosion is logically grouped according to mechanisms rather than arbitrarily separated into different types of corrosion as if they were unrelated. For those university students and industry personnel who approach corrosion theory very hesitantly, this text will present ...
An /alpha//sub 2/-adrenergic receptor subtype has been cloned from a human kidney cDNA library using the gene for the human platelet /alpha//sub 2/-adrenergic receptor as a probe. The deduced amino acid sequence resembles the human platelet /alpha//sub 2/-adrenergic receptor and is consistent with the structure of other members of he family of guanine nucleotide-binding protein-coupled receptors. The cDNA was expressed in a mammalian cell line (COS-7), and the /alpha//sub 2/-adrenergic ligand (/sup 3/H)rauwolscine was bound. Competition curve analysis with a variety of adrenergic ligands suggests that this cDNA clone represents the /alpha//sub 2/B-adrenergic receptor. The gene for this receptor is on human chromosome 4, whereas the gene for the human platelet /alpha//sub 2/-adrenergic receptor (/alpha//sub 2/A) lies on chromosome 10. This ability to express the receptor in mammalian cells, free of other adrenergic receptor subtypes, should help ...
The malM locus of Streptococcus pneumoniae was cloned into one of the two PstI sites of the multicopy S. pneumoniae plasmid pMV158. To eliminate chromosomal transformants in the simultaneous selection for tetracycline resistance (coded by pMV158) and maltose utilization, the host cells contained a chromosomal deletion of the mal gene cluster. Two clones were isolated; one with a 3.3 kb insert (pLS70) which behaved like wild type with respect to maltose utilization, and another with a 2.9 kb insert (pLS69) which behaved as though it contained a down promoter mutation. Preliminary mapping of these clones by restriction analysis placed the 0.4kb deletion on a HindIII fragment in the interior of the chromosomal insert. The recombinant plasmids were able to transform over 50% of a recipient population to Mal/sup +/. Enzyme measurements of the clones indicated an overproduction of amylomaltase, constituting up to 10% of the total cellular protein, ...
Several recent experiments on micro- (or nano-) structured samples of ferromagnetic materials are introduced. Magnetization reversal phenomena are investigated on submicron wire samples of trilayer structure using the giant magnetoresistance effect. Domain wall movements are sensitively monitored by resistivity measurements and the velocity of propagation is determined. The contribution of domain wall to the resistivity is argued from the results on artificially designed samples of a spring-magnet system. In circular dots of permalloy, the existence of vortex magnetization is confirmed and the reversal of the vortex core magnetization is studied from magnetic force microscopy measurements. (author)
To investigate the magnetic fluctuations and for further transport study, the poloidal and radial magnetic field measurement is conducted on the Sino United Spherical Tokamak (SUNIST). Auto-power spectral density indicates that the magnetic fluctuation energy mainly concentrates in the frequency region lower than 10 kHz. The magnetic field oscillations, which are characterized by harmonic frequencies of 40 kHz, are observed in the scrape-off layer; by contrast, in the plasma core, the magnetic fluctuations are of Gaussian type. The time-frequency profiles show that the poloidal magnetic fluctuations are temporally intermittent. The autocorrelation calculation indicates that the fluctuations in decorrelation time vary between the core and the edge. (authors)
Our research in the general area of acid catalysis involves the characterization of solid acidity and the corresponding assessment of catalytic performance of acidic materials. Acid characterization studies are required to provide essential information about the type of acid site (i.e., Lewis versus Bronsted), the strength of the sites, and the mobility of molecules adsorbed on the acid sites. An accurate measure of acid strength is given by the heat of adsorption of a basic probe molecule on the acid site. A thermodynamic representation of the mobility of adsorbed species on these sites is given by the entropy of adsorption. Important techniques used in these acid site characterization studies include microcalorimetry, thermogravimetric measurements, temperature programmed desorption, infrared spectroscopy and solid state nuclear magnetic resonance. The combination of these acid site characterization studies with reaction kinetics measurements of ...
A series of 2-alkylthiopyrine-4-carbothioamides were synthesized, and their anti-fungal potency was tested. The chemical structures were proved by infrared spectroscopy (IR) and {sup 1}H nuclear magnetic resonance ({sup 1}H-NMR) data and by elemental analysis. The minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) assessment were used for the estimation of potential activity in vitro. The study comprising 21 clinical isolates of fungi showed that two compounds exhibited fair inhibitory activity against some yeasts and dermatophytes. Selective fungistatic activity against non-dermatophytes (MIC = 3.12-25.0 {mu}g/mL) was found also in another compound. None of the above compounds showed inhibitory activity against non-dermatophyte filamentous fungi. Microbiological activity of 2-alkylthiopyridine-4-carbothioamides appears to be mainly related to hydrophobicity of alkyl in position 2. (authors). 10 refs., 8 tabs.
The lipid obtained by the toluene extraction of a dried raw Atlanta sewage sludge by the Soxhlet method, was pyrolyzed over activated alumina at atmospheric pressure. A range of weight hourly space velocities (WHSV) from 0.22-1.60/h and a range of temperatures from 400-480[degree]C were selected. A 70 wt % yield of light liquid hydrocarbons was obtained at a WHSV of 0.46/h and 450[degree]C. The sulfur and nitrogen contents of the pyrolysis products were much lower than products from direct liquefaction of sludge. Infrared spectra and [sup 13]C nuclear magnetic resonance confirmed the absence of carbonyl groups in the products. Gas chromatography showed a uniform hydrocarbon chain length distribution across the C[sub 7] to C[sub 17] mass range. The gas product consisted mainly of carbon dioxide and hydrocarbons. Lauric acid was used as a model to study the decarboxylation. The effects of catalyst loading and catalyst moisture content were ...
For the purpose of proposing it to ISO, the R and D were conducted of a new evaluation method of thermal properties of polymer materials. The FY 1999 results were summarized. In this fiscal year, the development of the ac Joule heating equipment was proceeded with based on the study at the technical committee, and the measuring device was installed. In the comparative measurement with conventional methods, study was proceeded with of the laser flash method, AC calorimetry method and specific heat measurement. In the technical survey, the developmental state of the ac method, especially, was examined as a testing method of thermal properties of polymer materials. It is in the stage of the basic research by keyword selection, and the search for literature is to be made in full scale. As to the needs in the industrial circle, as a result of the questionnaire survey made, it was found out that there were a wide variety of the needs for general-purpose/functional film ...
BC Hydro recently conducted a demonstration test of a bearing condition monitor. The test, at the 529-MW Kootenay Canal project, proved the ability of the monitor to detect machine condition faults. The capability to detect changing conditions during normal operation of hydroelectric machines gives hydro plant owners the opportunity to anticipate needed maintenance and ultimately to reduce the number of equipment failures. BC Hydro intends to install bearing condition monitors, as well as windings monitors, brushgear monitors, environmental monitors, and other selected systems in as many as 46 of its hydro generators. BC Hydro analyzed forced outages between 1985 and 1989 in its hydro system to identify which parts of a generating unit resulted in the highest number of hours of outage. From there, the utility has formulated a concept for a machine condition monitoring system. To keep the system cost effective, it will be developed in modules. In this way, users can ...
Small angle neutron scattering (SANS) has been a very powerful tool to study nanoscale (1-100 nm) bulk structures in various materials such as polymer, self assembled materials, nano-porous materials, nano-magnetic materials, metal and ceramics. Understanding the importance of the SANS instrument, the 8m SANS instrument was installed at the CN beam port of HANARO in 2001. However, without having a cold neutron source, the beam intensity is fairly low and the Q-range is rather limited due to short instrument length. In July 1, 2003, therefore, the HANARO cold neutron research facility project was launched and a state of the art 40m SANS instrument was selected as top-priority instrument. The development of the 40m SANS instrument was completed as a joint project between Korea Advanced Institute of Science and Technology and the HANARO in 2010. Here, we report the specification of a state of art 40m SANS instrument at HANARO
The authors present a comparison between the diagnostic accuracy of Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) in the articular pathologies of the knee. CT and MRI were performed in 30 patients who subsequently underwent surgery. CT and MRI results were compared on three bases: technique, definition of normal anatomy, and diagnostic accuracy. CT allowed a standardization of the technique, while MRI was superior in defining normal anatomy - especially in the study of capsulo-ligamentous structures. In all cases the use of both CT and MRI allowed a correct diagnosis, showing the site, extent and gravity of the lesion. CT proved to be superior to MRI in 4 cases, while MRI corrected CT diagnosis in 11 cases; in 15 patients both techniques had the same diagnostic accuracy. Meniscal tears were better identified by CT, while MRI was superior in the detection of ligamentous lesions and in the characterization of PVNS and tendinitis of the patellar ...
For many centuries paper was the main material for recording cultural achievements all over the world. Paper is mostly made from cellulose with small amounts of organic and inorganic additives, which allow its identification and characterization and may also contribute to its degradation. Prior to 1850, paper was made entirely from rags, using hemp, flax and cotton fibres. After this period, due to the enormous increase in demand, wood pulp began to be commonly used as raw material, resulting in rapid degradation of paper. Spectroscopic techniques represent one of the most powerful tools to investigate the constituents of paper documents in order to establish its identification and its state of degradation. This review describes the application of selected spectroscopic techniques used for paper characterization and conservation. The spectroscopic techniques that have been used and will be reviewed include: Fourier-Transform Infrared spectroscopy, Raman ...
Power source requirements for the military were presented to provide guidelines for research and development planning. Power sources that contain a high amount of energy and are small, light and durable are a common request from military users. Safety, reliability and low temperature performance are also important factors in the selection of power sources, as are cost and energy efficiency. Issues concerning advanced batteries were reviewed with reference to high energy density cathode materials. Various thermoelectric and renewable energy materials were discussed, with reference to recovery and conversion of waste heat. It was suggested that photovoltaic devices could help revolutionize military logistics by modifying energy re-supply requirements. Solid Oxide Fuel Cells (SOFC) were considered in relation to the high price of the ceramic materials required for operation. It was noted that the development of SOFC anodes capable of generating ...
Asialoorosomucoid (ASOR) is internalized and degraded by HepG2 cells after binding to the asialoglycoprotein (ASGP) receptor, internalization through the coated pit/coated vesicle pathway, and trafficking to lysosomes. Primaquine, an 8-aminoquinoline antimalarial compound, inhibits ASOR degradation at concentrations greater than 0.2 mM by neutralizing intracellular acid compartments. This leads to alterations in surface receptor number, receptor-ligand dissociation, and receptor recycling. We have investigated the effects of primaquine on 125I-ASOR uptake and degradation as a function of primaquine concentration and duration of exposure. Concentrations below those required for neutralization of acidic compartments block 125I-ASOR degradation in HepG2 cells and lead to intracellular ligand accumulation. This effect is maximal at 80 microM primaquine. The intracellular 125I-ASOR is undegraded, dissociated from the ASGP receptor, and contained ...
Asialoorosomucoid (ASOR) is internalized and degraded by HepG2 cells after binding to the asialoglycoprotein (ASGP) receptor, internalization through the coated pit/coated vesicle pathway, and trafficking to lysosomes. Primaquine, an 8-aminoquinoline antimalarial compound, inhibits ASOR degradation at concentrations greater than 0.2 mM by neutralizing intracellular acid compartments. This leads to alterations in surface receptor number, receptor-ligand dissociation, and receptor recycling. We have investigated the effects of primaquine on 125I-ASOR uptake and degradation as a function of primaquine concentration and duration of exposure. Concentrations below those required for neutralization of acidic compartments block 125I-ASOR degradation in HepG2 cells and lead to intracellular ligand accumulation. This effect is maximal at 80 microM primaquine. The intracellular 125I-ASOR is undegraded, dissociated from the ASGP receptor, and contained ...
Laser-assisted processing techniques for producing high-quality solar cell metallization patterns have been investigated, developed, and characterized. During the early stages, preliminary investigations were carried out on a variety of promising laser-assisted metallization schemes, and the best of these was selected for further development. A comprehensive literature search initially yielded information on state-of-the-art laser-assisted techniques for metal deposition such as laser chemical vapor deposition and laser photolysis of organometallics, as well as laser-enhanced electroplating. Initial experiments on laser-enhanced electroplating yielded very promising results with linewidths as narrow as 25 ..mu..m and local plating speeds as high as 12 ..mu..m/s being achieved. Metal deposition experiments were carried out utilizing laser-assisted pyrolysis of a variety of metal-bearing polymer films and metallo-organic inks spun onto silicon ...
Candoxin (PDB #1JGK), a three-finger neurotoxin from Bungarus candidus venom, inhibits post-synaptic neuromuscular and neuronal alpha7nACh-receptors, and induces delayed cell-death throughout the glial population. When applied to cultured human glial cell lines, candoxin (CDX) induced cell death in a concentration (EC(50) approximately 1muM) and time dependent manner. Results of TUNEL-histochemistry further confirm CDX-induced brain (hippocampus, frontal cortex, and temporal regions) damage when administered intracerebroventricularly (i.c.v) in adult mice. In this study, we explored differential gene expression profiles following exposure of human glial (Hs 683) cell lines to CDX at various time intervals using Affymetrix-GeneChips. By means of MAS and GeneSpring analyses, 105 genes whose expression was significantly (P<0.01) altered by at least 3-fold were selected. Results of ...
This dissertation is concerned with the development, experimental diagnostics and mathematical modelling and simulation of polymer electrolyte fuel cells (PEFC). The central themes throughout this thesis are the closely interlinked phenomena of mass and charge transfer. In the face of developing a PEFC system for vehicle propulsion these phenomena are scrutinized on a broad range of relevant scales. Starting from the material related level of the membrane and the gas diffusion layer (GDL) we turn to length scales, where structural features of the cell additionally come into play. These are the scale of flow channels and ribs, the single cell and the cell stack followed by the cell, stack, and system development for an automotive power train. In Chapter 3 selected fundamental material models and properties, respectively, are explored that are crucial for the ...
The Ringold Formation consists of lacustrine and fluvial deposits overlying the Columbia River Basalt. The Ringold Formation, because of its thickness, extent, and age, is an excellent unit in which to detect and possibly data the deformation that has occurred since deposition of the basalt. One objective of this study was to investigate the paleomagnetism of the upper Ringold unit exposed at one location in the White Bluffs in enough detail to resolve, with reasonable confidence, the magnetostratigraphy of the rock units sampled. The other objective was to evaluate, in a preliminary manner, the paleomagnetic favorability and magnetostratigraphy of the subsurface Ringold Formation in the Pasco Basin and at selected exposures outside the Pasco Basin. The scope of this study was the collection of 300 paleomagnetic samples, their measurement, and analysis. Samples were collected from the White Bluffs, from core recovered from six drill holes on the Hanford Site, and ...
Dosimetry is evaluated for live-line workers exposed to 50 Hz non-uniform magnetic fields from typical high-voltage transmission lines in the United Kingdom. The configurations involve twin-, triple- and quadruple-conductor transmission line bundles. Scenarios include three worker postures for the twin and triple bundles, and four postures for the quadruple bundle. The postures are selected to simulate worst case scenarios representative of work practices and result in highest values of dosimetric measures in critical organs. Only single-phase bundles are considered, as adjacent bundles of differing phase result only in a small reduction of the dosimetric measures. Reported data include various measures of the electric field and current density induced in tissues, as well as of the current density averaged over 1 cm"2 areas normal to the current flow. A value of this latter quantity of 10 mA m"-"2 is suggested as a threshold for neural tissue ...
Selected case studies of auroral structure/activity observed at different local times on the dayside are presented and discussed in the context of electrodynamic coupling between the different magnetospheric boundary regions and the ionosphere. The first case addresses the question of the auroral signatures of the two boundary regions referred to as cusp and cleft/LLBL. Combined ground-based and satellite data reveal the different latitudinal zones of auroral forms/particle precipitation/field-aligned current and the relationship with the respective magnetospheric plasma populations, i.e. CPS, BPS, LLBL, and the plasma mantle. Midday auroral breakup events and the related ionospheric ion drift and magnetic observations show many of the features that have been predicted to be ionospheric signatures of flux transfer events. An alternative explanation that has been proposed by others, i.e. ionospheric effect of magnetopause perturbations excited ...
Three-dimensional dynamics of a compact toroid (CT) plasmoid, which is injected into a magnetized target plasma region is investigated by using magnetohydrodynamic (MHD) numerical simulations. It is found that the process of the CT penetration into this region is much more complicated than what has been analyzed so far by using a conducting sphere (CS) model. The injected CT suffers from a tilting instability, which grows with the similar time scale as the CT penetration. The instability is accompanied by magnetic reconnection between the CT magnetic field and the target magnetic field, which disrupts the magnetic configuration of the CT. Magnetic reconnection plays a role to supply the high density plasma initially confined in the CT magnetic field into the target region. Also, the penetration depth of the CT high density plasma is ...
Potassium clusters arrayed in zeolite A are known to show ferromagnetic properties at low temperature. The origin of the spontaneous magnetization has been explained by a model of spin-canting in an antiferromagnetically ordered state. The direct information for the magnetic structure, however, has not been obtained so far. In the present work, we measure the neutron powder diffraction by using pulsed neutron source at KEK-KENS below and above the Curie temperature. No significant temperature-dependence was, however, obtained within the statistical errors, namely, magnetic scattering could not be detected separately. We also estimate the intensity of magnetic scattering by assuming some possible magnetic structures with considering the magnetic form factor of the cluster wave function. The intensity of magnetic scattering is estimated to be ...
Potassium clusters arrayed in zeolite A are known to show ferromagnetic properties at low temperature. The origin of the spontaneous magnetization has been explained by a model of spin-canting in an antiferromagnetically ordered state. The direct information for the magnetic structure, however, has not been obtained so far. In the present work, we measure the neutron powder diffraction by using pulsed neutron source at KEK-KENS below and above the Curie temperature. No significant temperature-dependence was, however, obtained within the statistical errors, namely, magnetic scattering could not be detected separately. We also estimate the intensity of magnetic scattering by assuming some possible magnetic structures with considering the magnetic form factor of the cluster wave function. The intensity of magnetic scattering is estimated to be ...
Scanning ion microscopy with polarization analysis (SIMPA) is used to study the spin-resolved surface magnetic structure of nano-sized magnetic systems. SIMPA is utilized for in situ topographic and spin-resolved magnetic domain imaging as well as for focused ion beam (FIB) etching of desired structures in magnetic or non-magnetic systems. Ultra-thin Co films are deposited on surfaces of Si(1 0 0) substrates, and ultra-thin, tri-layered, bct Fe(1 0 0)/Mn/bct Fe(1 0 0) wedged magnetic structures are deposited on fcc Pd(1 0 0) substrates. SIMPA experiments clearly show that ion-induced electrons emitted from magnetic surfaces exhibit non-zero electron spin polarization (ESP), whereas electrons emitted from non-magnetic surfaces such as Si and Pd exhibit zero ESP, which can be used to calibrate sputtering rates in situ. We ...
A number of interactions between magnetic fields and matter is reviewed. The resulting forces range in magnitude from the very large, obtained in high-energy fields, to the weak ones caused by the magnetostriction of ferromagnets. The fundamentals of these interactions are highlighted, and the examples discussed are forces on dipoles, particle alignment, magnetostrictive forces, magnetic forming, magnetic stirring, levitation melting, and magnetic pulsing of tool steels. (orig.)
A model is available in predicting flocculation frequencies between particles of various properties under the influence of a magnetic field. This model provides a basic understanding of fundamental phenomena, such as particle-particle and particle-collector interactions, occurring in HGMF (high gradient magnetic field), and will be extended to describe experimental data of particle flocculation and filtration and predict the performance of high- gradient magnetic filters. It is also expected that this model will eventually lead to a tool for design and optimization of magnetic filters for environmental, metallurgical, biochemical, and other applications.
Human bone marrow mesenchymal stem cells (BM-MSC) are multipotent progenitor cells that have transient immunomodulatory properties on Natural Killer (NK) cells, Dendritic Cells (DC), and T cells. This...Full Text Available
Due to the increasingly stricter regulations for deep reduction of fuel sulfur content, development of new deep desulfurization processes for liquid transport fuels has become one of the major challenges to the refining industry and to the production of hydrocarbon fuels for fuel cell applications. The sulfur compounds in the current transport fuels corresponding to the S level of 350-500 ppm account for only about 0.12-0.25 wt % of the fuel. The conventional hydrotreating approaches will need to increase catalyst bed volume at high-temperature and high-pressure conditions for treating 100 % of the whole fuel in order to convert the fuel mass of less than 0.25 wt %. In the present study, we are exploring a novel adsorption process for desulfurization at low temperatures, which can effectively reduce the sulfur content in gasoline, jet fuel and diesel fuel at low investment and operating cost to meet the needs for ultra-clean transportation fuels and for fuel ...
A carrier-free radioiodinated phenylazide derivative of forskolin, 3-iodo-4-azidophenethylamido-7-O-succinyl-deacetyl-forskolin (({sup 125}I)IAPS-forskolin), has been shown to be a highly selective photoaffinity probe for the human erythrocyte glucose transported and the glucose transport proteins found in several mammalian tissues and cultured cells where the glucose transport protein is present at a low concentration. The photoincorporation of ({sup 125}I)IAPS-forskolin into these glucose transporters was blocked by D- (but not L-) glucose, cytochalasin B, and forskolin. In addition to labeling the mammalian glucose transport proteins, ({sup 125}I)IAPS-forskolin also labeled the L-arabinose transporter from E. coli. In muscle and adipose tissues, glucose transport is markedly increased in response to insulin. ({sup 125}I)IAPS-forskolin was shown to selectivity tag the glucose transporter in membranes derived from these ...
A carrier-free radioiodinated phenylazide derivative of forskolin, 3-iodo-4-azidophenethylamido-7-O-succinyl-deacetyl-forskolin (["1"2"5I]IAPS-forskolin), has been shown to be a highly selective photoaffinity probe for the human erythrocyte glucose transported and the glucose transport proteins found in several mammalian tissues and cultured cells where the glucose transport protein is present at a low concentration. The photoincorporation of ["1"2"5I]IAPS-forskolin into these glucose transporters was blocked by D- (but not L-) glucose, cytochalasin B, and forskolin. In addition to labeling the mammalian glucose transport proteins, ["1"2"5I]IAPS-forskolin also labeled the L-arabinose transporter from E. coli. In muscle and adipose tissues, glucose transport is markedly increased in response to insulin. ["1"2"5I]IAPS-forskolin was shown to selectivity tag the glucose transporter in membranes derived from these ...
Alloys of zirconium are widely used in various core components of power reactors. Nuclear assemblies require high degree of reliability and integrity for performing in radiation and corrosive atmosphere. The hostile environments of reactor core and inaccessibility for repairs make it mandatory to select only those joining techniques which produce not only superior quality but are also amenable to NDT methods and such other techniques which ensure acceptable performance. The author has worked on various types of welding of zirconium alloys for different applications. Modern techniques in electron beam (EB) welding, resistance welding, GTAW welding and laser welding have been developed for joining Zr alloys components for different types of reactors. Many of these have been standardized and successfully used in production. Several advancements have been made in the welding technologies towards achieving high productivity and increased reliability with economy and ...
Motivation: Automatic recognition of cell identities is critical for quantitative measurement, targeting and manipulation of cells of model animals at single-cell resolution. It has been...Full Text Available
Formaldehyde, a well-identified indoor pollutant, was recently classified as carcinogenic. New regulations for the air quality are expected and therefore there is a need for low-cost sensors, sensitive and selective with a fast response time for the detection of formaldehyde at ppb level. In the present work, we had developed a chemical sensor based on nano-porous matrices doped with Fluoral-P and optical methods of detection. The nano-porous matrices, elaborated via the Sol-Gel process, display nano-pores whose cavity is tailored for the trapping of the targeted pollutant. They provide a first selectivity with the discrimination of the pollutants by their size. A second selectivity is obtained with a molecular probe, Fluoral-P, which reacts specifically with formaldehyde leading to the 3,5- di-acetyl-1,4-dihydro-lutidine (DDL). The kinetics of formation of DDL was studied as function of many parameters such as the ...
Magnetic resonance imaging (MRI) as a diagnostic imaging tool relies on the generation of magnetic fields, whereas the computerized tomography (CT) uses X-radiation. The fundamental principle of MRI is the magnetic resonance of paramagnetic atomic nuclei. These nuclei, as e.g. protons (= hydrogen nuclei), are aligned in required orientation by application of a strong magnetic field. Upon simultaneous application of an electromagnetic high-frequency field perpendicular to the axis of the basic magnetic field, and in response to periodical changing of the electromagnetic field at a given frequency, the originally aligned paramagnetic nuclei are forced into a movement similar to that of a ``whipping top``. When the resonance frequency is shut off, the nuclei return to their former, aligned positions, inducing a weak signal in a coil. The series of signals generated by multiple ...
Abstract in english We present a detailed derivation of the effective dielectric constant to be used in the dispersion relation for electrostatic waves in the case of a plasma immersed in a inhomogeneous magnetic field, with inhomogeneity perpendicular to the direction of the magnetic field.
A tutorial account is given of the main characteristics and distinctive features of conceptual magnetic fusion systems employing the magnetic mirror principle. These features are related to the potential advantages that mirror-based fusion systems may exhibit for the generation of economic fusion power.
An analytic model of magnetic torques applied to an accreting neutron star is employed to evaluate the magnetic dipole moments of x-ray pulsars. A new type of close binary system containing a neutron star is suggested.
An introduction to time-of-flight neutron spectroscopy is presented in the context of the study of magnetic materials. Examples are taken from the class of rare earth and actinide magnetic materials known as `strongly correlated electron` systems. (author) 11 figs., 24 refs.
The past decade has seen the development of eddy current probes for inspection of the mildly ferro-magnetic alloy Monel 400. Due to the rapid advances in permanent magnet technology similar probes have been upgraded to magnetically saturate, and hence ins...
The disclosure is directed to an active magnetic regenerator apparatus and method. Brayton, Stirling, Ericsson, and Carnot cycles and the like may be utilized in an active magnetic regenerator to provide efficient refrigeration over relatively large temperature ranges.
The solid-pseudopapillary tumor (SPT) of the pancreas is a rare type of exocrine pancreatic neoplasm. SPT predominantly affects young women and female children, and is usually discovered incidentally. This tumor is generally benign with a low incidence of malignancy. A 13-year-old girl was admitted to the hospital with a few weeks' history of mild abdominal pain and jaundice. On physical examination, there was no palpable mass. The laboratory tests showed increased SR, CRP, high bilirubin, amylase and lipase serum levels. Ultrasound imaging revealed a solid lesion in the region of the pancreatic head. On MRI, precise tumor localization in the head of the pancreas with pancreatic duct dilatation and compression of the common bile duct were visualized. Pancreaticoduodenectomy and cholecystectomy was performed with good clinical outcome. Microscopic and immunohistochemical studies indicated that tumor cells were typical of SPT without any signs of malignancy. After ...
Ewing's sarcoma is a highly malignant neoplasm of the bone whose origin is still uncertain. A strong relationship exists between Ewing's sarcoma and tumors of neural origin (Ewing family of tumors). Ewing's sarcoma must be distinguished from other round-cell tumors like lymphoma and neuroblastoma and also must be differentiated from osteogenic sarcomas. On plain radiographs, Ewing's sarcoma appears as a lytic or mixed lytic-sclerotic, rarely as predominantly sclerotic lesion with margins Lodwick grade III. It is located primarily in the diaphyseal and metadiaphyseal regions of the long bones of the lower extremities. A large soft tissue tumor is usually present. Magnetic resonance imaging is the imaging modality of choice to evaluate the extent of the primary lesion, to monitor the response to neoadjuvant chemotherapy and to follow up non-resected Ewing's sarcomas. Bone scintigraphy is necessary to detect skeletal metastasis, and "2"0"1thallium ...
Five cases diagnosed as extraosseous Ewing's sarcoma (EES) during a 15 year period, and the relevant literature, were reviewed. The diagnosis in these cases was difficult to confirm, mainly because the distinction between the osseous form of Ewing's sarcoma (OES) and either periosteal reactions or direct tumour invasion into adjacent bone by EES was often unclear. The literature suggests that other authors have also encountered difficulties. The authors believe that many cases reported as EES are likely to have been OES. This distinction has some importance, as the two conditions are usually treated in differing ways. The following criteria are proposed for the diagnosis of primary EES: (i) no evidence of bony involvement on magnetic resonance imaging; (ii) no evidence of increased uptake in bone or periosteum adjacent to the tumour on static isotope bone scan images; (iii) a small round cell tumour with no differentiating features on light ...
The Neutron Science Project at Japan Atomic Energy Research Institute has been proposed for the research of nuclear transmutation technology and the basic science with a spallation neutron source. The project calls for an 8MW proton linac which accelerates 5.3mA average current cw and pulsed beams up to 1.5GeV. The superconducting (SC) rf-cavity is the main option for the energy part from 100MeV to 1.5GeV because by using the SC structure, less power is consumed in cw operation than by using a normal conducting (NC) structure. A conceptual design study of the superconducting proton linac is reported. The SC linac is composed of 8 {beta} sections. Each section has the identical 5-cell cavities with the surface peak field of 16MV/m. The total number of cavities is 284, and the length of the SC linac is 690m. The lattice design is determined with the equipartitioned condition and the matched envelope equations for the minimum emittance growth. The transverse and ...
Parameters of permanent magnets result from the combination of intrinsic properties such as saturation magnetization, magnetic exchange, and magnetocrystalline energy, as well as microstructural parameters such as phase structure, grain size, and orientation. Reduction of grain size into nanocrystalline regime (#approx# 50 nm) leads to the enhanced remanence which derives from ferromagnetic exchange coupling between highly refined grains. In this study the fundamental phenomena, quantities, and structure parameters, which define nanophase permanent magnets are presented and discussed. The theoretical considerations are confronted with experimental data for nanocrystalline Sm-Fe-N type permanent magnets. (author)
Development of selective serotonin transporter (SERT) tracers for single-photon emission tomography (SPET) is important for studying the underlying pharmacology and interaction of specific serotonin reuptake site inhibitors, commonly used antidepressants, at the SERT sites in the human brain. In search of a new tracer for imaging SERT, IDAM (5-iodo-2-[[2-2-[(dimethylamino)methyl]phenyl]thio]benzyl alcohol) was developed. In vitro characterization of IDAM was carried out with binding studies in cell lines and rat tissue homogenates. In vivo binding of [[sup 125]I]IDAM was evaluated in rats by comparing the uptakes in different brain regions through tissue dissections and ex vivo autoradiography. In vitro binding study showed that IDAM displayed an excellent affinity to SERT sites (K[sub i]=0.097 nM, using membrane preparations of LLC-PK[sub 1] cells expressing the specific transporter) and showed more than 1000-fold of ...
To assess the utility of magnetic resonance (MR) imaging in the study of pediatric patients with clinical suspicion of pituitary disease. We studied 18 patients aged 7 to 18 years.Fifteen had hormonal disturbances, two presented amenorrhea and 1 complained of headache, fever and symptoms of polyuria and polydipsia. All the patients were examined using a Siemens SP 42 1-Tesla MRI scanner. Sagittal and coronal T1-weighted spin-echo images were obtained; in addition T2-weighted spin-echo or fast spin-echo imaging was performed in ten cases and intravenous gadolinium was administered in nine. We found 9 patients with hypothalamic-pituitary dysgenesis, 2 with germinoma, 2 cases of pituitary hemosiderosis in patients with thalassemia, 2 cases of microadenoma, one abscess, one case of idiopathic central diabetes insipidus and one of Langerhans cell histiocytosis. MR enabled us to assess pituitary structural alterations in children with ...
Early white matter (WM) injury affects brain maturation in preterm infants as revealed by diffusion tensor imaging and volumetric magnetic resonance (MR) imaging at term postmenstrual age (PMA). The aim of the study was to assess quantitatively brain maturation in preterm infants with and without milder forms of WM damage (punctate WM lesions, PWML) using conventional MRI. Brain development was quantitatively assessed using a previously validated scoring system (total maturation score, TMS) which utilizes four parameters (progressive myelination and cortical infolding, progressive involution of glial cell migration bands and germinal matrix tissue). PWML were defined as foci of increased signal on T1-weighted images and decreased signal on T2-weighted images with no evidence of cystic degeneration. A group of 22 preterm infants with PWML at term PMA (PWML group) were compared with 22 matched controls with a normal MR appearance. The two groups ...
Crystals of disamarium rhenium (IV) pentoxide, Sm{sub 2}ReO{sub 5}, were obtained by subsolidus reaction of samariumsesquioxide and rheniumdioxide (ratio 1:1) in sealed Pt 10Rh tubes at 1673 K. The structure was determined by single-crystal X-ray diffraction. Sm{sub 2}ReO{sub 5} crystallizes in the tetragonal system with unit cell dimensions a = 8.646(3) {angstrom} and c = 5.747(2) {angstrom} and space group P4/n (no. 85) with Z = 4. The structure consists of isolated RE{sub 2}O{sub 8} groups and the (Sm{sub 4}O) chains are inter-connected by common oxygen atoms to form a three-dimensional network. Each Re{sub 2}O{sub 8} group is composed of a pair of rhenium each surrounded by four oxygens with a short Re-Re distance of 2.251(1) {angstrom} indicating a metal-metal bond. Rhenium has the formal oxidation state of +4. The observed magnetizations in the temperature range 1.8 < T < 100 K exhibits antiferromagnetic ordering below 2.4(1) K and ...
Forty-four patients with small cell carcinoma of the bronchus underwent CT and MR studies of the brain to detect cerebral metastases. All patients were studied with contrast-enhanced CT scans, short (T1-weighted) and long (T2-weighted), spin-echo (SE) and FLASH 90 grades sequences were also obtained. A quantitative comparison of the results was carried out to assess the sensitivity of the different techniques in the detection of brain metastases according to lesion diameter. Metastases were identified in 19/44 patients (43%). All techniques detected the lesions >2 cm; of the metastases <2 cm, 63/124 (51%) were detected only by GdDTPA SE-T1 and FLASH sequences and 11 more (9%) only by Gd-DTPA SE-T1 scans. All the lesions identified oh enhanced CT scans or on T2-weighted images were easily detected by Gd-DTPA scans. CT sensitivity was higher than that of pre-contrast SE-T1 and FLASH studies and only slightly lower than that of T2-weighted images. As for lesions ...
The molar heat capacities (Cp,m) of a series of synthetic forsterite (Fo)-fayalite (Fa), (Mg2SiO4+Fe2SiO4), olivines have been measured between 5K and 300K on milligram-sized samples with the Physical Properties Measurement System (Quantum Design(R)). Sharp, ?-type heat capacity anomalies are observed in the Fe-rich compositions fayalite, Fo10Fa90, Fo20Fa80, Fo30Fa70, and Fo40Fa60. The corresponding Neel temperatures TN decrease linearly from 64.5K in fayalite to 32.8K in Fo40Fa60 following the relationship TN=79.02.xFa-14.07. Fo50Fa50 and Mg-richer olivines show weak broad features in the heat capacity data around 15K to 20K that decrease in magnitude with increasing forsterite content. In order to derive and separate molar electronic, magnetic and vibrational heat capacity contributions, Cel,m, Cmag,m, and Cvib,m from the experimental heat capacities (Ctot,m), we used a single-parametric phonon dispersion model to calculate Cvib,m for the solid-solution members ...
Principle advantages of magnetic forming for part manufacture appear to lie ... to be an area of great potential for the magnetic forming process. We have a ...
OBJECTIVE--The study was performed to examine the influence of the exposure to magnetic fields in the potrooms of an electrolysis plant on the occurrence of musculoskeletal symptoms among the employees....Full Text Available
Several refrigerators for liquid helium and liquid nitrogen systems have been integrated successfully into IGC manufactured whole body Magnetic Resonance Imaging (MRI) magnet systems. The refrigerators have been tested in systems with magnetic fields of 0.6T to 1.5T. Tests were performed to study the effectiveness of the refrigerators, the magnetic field effects on the refrigerators, the effect of the refrigerators on the field uniformity and magnetic resonance image quality. The interface between the refrigerator and the whole body MRI magnet system cryostat was specifically designed to allow retrofit to the existing IGC magnet systems, while ensuring good heat transfer characteristics and good vibration isolation from the cryostat. The interface between the refrigerator and the cryostat and the refrigerator test results are presented.
The Muon Ionization Cooling Experiment (MICE) focusing solenoid magnets focus the muon beam within the MICE cooling channel on a liquid or solid absorber that is within the warm bore of solenoid. The focusing magnet has a warm bore of 470 mm. his magnet consists of two coils 210-mm long that is separated by an aluminum mandrel that is 200 mm long. Each of the coils has its own leads. The coils may be operated in either the non-flip mode (solenoid mode with both coils at the same polarity) or the lip mode (quadrupole focusing mode where both coils are at opposite polarity). This report describes the focusing solenoid magnet design that will be built by the vendor. The progress on the construction of the first of the focusing magnets will also be discussed in this report. Ultimately three of these magnets will be built. These magnets will be ...
The ternary rare earth compound NdRh_4B_4 has been studied by means of critical field, low temperature heat capacity, and static magnetic susceptibility measurements. Features in the upper critical field and heat capacity data at 1.31 K and 0.89 K suggest the occurrence of long-range magnetic order in the superconducting state. The temperature dependence of the static magnetic susceptibility follows a Curie-Weiss law with an effective magnetic moment #mu#sub(eff) = 3.58 +- 0.05 #mu#sub(B) and a Curie-Weiss temperature thetasub(p) = -6.2 +- 1.0 K between 20 K and room temperature. However, magnetization vs. applied magnetic field isotherms suggest the development of a ferromagnetic component in the Nd"3"+ magnetization at low temperatures. (author).
Highly ordered arrays of Ni nanoholes and Fe{sub 20}Ni{sub 80} antidots have been prepared, respectively, by replica/antireplica processing and sputtering techniques using nanoporous alumina membranes as templates. Geometrical characteristics as nanohole/antidot diameter, interpore distance and the overall hexagonal symmetry of arrays are controlled through the original templates. Experimental data on their hysteresis and magnetic domain structure have been taken by vibrating sample magnetometry and magnetic force microscopy, respectively. An analysis of the magnetization process, resulting magnetic anisotropy and magnetic domain structure is summarized considering the influence of those geometry aspects. In particular, the hexagonal symmetry and the density of nanohole/antidots determine the overall magnetic behavior, which is of interest in future high-density ...
Highly ordered arrays of Ni nanoholes and Fe20Ni80 antidots have been prepared, respectively, by replica/antireplica processing and sputtering techniques using nanoporous alumina membranes as templates. Geometrical characteristics as nanohole/antidot diameter, interpore distance and the overall hexagonal symmetry of arrays are controlled through the original templates. Experimental data on their hysteresis and magnetic domain structure have been taken by vibrating sample magnetometry and magnetic force microscopy, respectively. An analysis of the magnetization process, resulting magnetic anisotropy and magnetic domain structure is summarized considering the influence of those geometry aspects. In particular, the hexagonal symmetry and the density of nanohole/antidots determine the overall magnetic behavior, which is of interest in future high-density ...
It is shown that plasma viscosity does not influence the magnetic island rotation directly. Nevertheless, it leads to nonstationarity of the plasma velocity. This nonstationarity is the reason of the viscosity effect on island rotation. (author)
... M(TH) in applied magnetic fields up to ± 7 T and for temperatures ranging from 2 to 300 K. The superparamagnetic (SPM) behavior of these metallic ...
Effective localization of small magnets against a noisy, real world background can involve various methods to first identify the magnetic fields produced by the magnet of interest, then to filter out background noise, and then to analyze the available magnetic field data to localize the magnet. Here we discuss low cost techniques which allow localization of small magnets with field strengths in the milliGauss range against real world background fields in the range of hundreds of mG, which may be fluctuating by up to tens of mG. Such techniques allow magnet tracking to be used to localize catheters in place of more invasive and expensive methods, e.g. fluoroscopy, for a variety of applications, including drug infusion with peripherally inserted central catheters (PICCs), laser ablation (TMR, PTMR) and introduction of pacemaker leads.
Development of Portable Normobaric Hypoxia and Pulsed Magnetic Field Firmware System for Enhancement of Radio- and Non-specific Resistance in Workers of Environmentally Hazardous Industries
The dynamic response of cylindrical and ring-shaped YBaCuO bulk parts to pulsed magnetic fields is calculated by using small sets of finite elements. Some comparisons with experimental results are provided, and they give confidence in the modelling of the superconducting properties. Transient magnetizations as a function of time and space as well as shapes and absolute values of trapped magnetic flux profiles are presented. The influence of the sample geometry is investigated for different millisecond pulsed magnetization processes. Results are reported for different radial thicknesses and heights, different pulse durations, peak magnetic fields and pulse sequences with and without stepwise cooling. Comparisons concerning the achievable trapped magnetic field and flux are made, and implications for the use of high-temperature superconductor bulk parts as ...
A nanosuspension of magnetically tagged metronidazole was developed by the solvent displacement method coupled with ultrasonication and was evaluated for its physicochemical properties. The drug release from metronidazole magnetic nanosuspension at pH 1.2 and 7.0 shows maximum correlation coefficient for zero order and Higuchi model, respectively. The anthelmintic activity of the formulated metronidazole magnetic nanosuspension was evaluated on Indian earthworms (Pheretima poi). Metronidazole magnetic nanosuspension at a dose of 10 and 50 mg/ml shortened by 31% and 34%, respectively, the mean time to death of the earthworms when compared against a non-magnetic metronidazole suspension. Thus, the developed metronidazole magnetic nanosuspension showed potent, controlled and targeted drug action and might be a good therapeutic avenue in combating infectious GI ...
With the increased costs of maintaining boilers and chillers entrepreneurs around the country have offered magnetic and similar devices to facilities as viable alternatives to their maintenance program. This report gives a brief history of some of the pre...
... design, and manufacturing knowledge have been acquired and used to develop an 'in-house' capability for the fabrication of magnetic forming coils ...
has been generally related to magnetic forming. One of the methods suggested was the following: A "pancake" magnetic coil is placed over a thin aluminum ...
From optical point of view and due to the magnetic interaction of the cold neutrons with the unpaired electron shell, magnetic materials hae a neutron spin-dependent refractive index n[sup +] [spin up] and n[sup -] [spin down]. Magnetic media such as Fe, Co and Ni react like birefringent uniaxial crystals in ordinary optica. n[sup +] and n[sup -] are the equivalent of the ordinary and extraordinary refractive indices. The specular reflection of spin polarized neutrons which is due to the discontinuity of the magnetic induction at the surface of the ferromagnet is a sensitive probe of surface and interface magnetism. We shall first give the background of the art of polarized neutron optics. Secondly, some recent examples from surface and interface magnetism will be given to illustrate the power of this technique such as the magnetic coupling ...
For the purpose of solving the limitations such as shape and dimension for magnetic compact fabricated by conventional anisotropic forming under magnetic orienting field, the feasibility of a new magnetic forming process was studied. Ferrite powder mixed with UV resin was compacted in the die mold and followed by alignment under the magnetic field. Effects of viscosity of UV resin and forming condition on magnetic characteristics of the compact was investigated. Maximum degree of alignment for the ferrite powder reached to 0.826. It was predicted that the proposed method had make it possible to fabricate a high performance magnet having the anisotropic alignment of the magnetic powder. The UV resin is desirable to have low viscosity, good properties such as formability and configuration stability for the compact and also parting- ability ...
magnet research at several national laboratories through its Advanced Accelerator Technology Program. The HEP Conductor Development Program, a collaboration among national...
Three regio-isomers of N-(N-benzylpiperidin-4-yl)-4-iodobenzamide, IBP, were prepared and evaluated for their sigma affinities. All three isomers (2, 3, and 4-substituted) showed high affinities for sigma-1 receptors in guinea pig brain membranes (Ki - 1.64 nM, 3.02 nM, 1.70 nM respectively) against ["3H]-(+)-pentazocine, a sigma-1 selective ligand. 2-IBP and 4-IBP showed modest affinities for sigma-2 sites in rat liver (Ki = 29.6 nM. 25.2 nM respectively) against ["3H]DTG in the presence of dextrallorphan to mask sigma-1 sites. The homologous competition binding studies of 4-["1"2"5I]BP in MCF-7 human breast tumor cells showed high affinity dose-dependent binding. Competition binding studies with haloperidol and DTG also showed a high affinity binding (Ki = 4.6 nM, 60 nM respectively), demonstrating the sigma specificity. The saturation binding (Scatchard analysis) of ["3H]DTG with MCF-7 cell membrane preparations gave Kd ...
Calcium-activated chloride channels (CaCCs) are widely expressed in mammalian tissues, including intestinal epithelia, where they facilitate fluid secretion. Potent, selective CaCC inhibitors have not been available. We established a high-throughput screen for identification of inhibitors of a human intestinal CaCC based on inhibition of ATP/carbachol-stimulated iodide influx in HT-29 cells after lentiviral infection with the yellow fluorescent halide-sensing protein YFP-H148Q/I152L. Screening of 50,000 diverse, drug-like compounds yielded six classes of putative CaCC inhibitors, two of which, 3-acyl-2-aminothiophenes and 5-aryl-2-aminothiazoles, inhibited by >95% iodide influx in HT-29 cells in response to multiple calcium-elevating agonists, including thapsigargin, without inhibition of calcium elevation, calcium-calmodulin kinase II activation, or cystic fibrosis transmembrane conductance regulator chloride channels. ...
The Maybell uranium mill tailings site is 25 miles (mi) (40 kilometers [km]) west of the town of Craig, Colorado, in Moffat County, in the northwestern part of the state. The unincorporated town of Maybell is 5 road mi (8 km) southwest of the site. The designated site covers approximately 110 acres (ac) (45 hectares [ha]) and consists of a concave-shaped tailings pile and rubble from the demolition of the mill buildings buried in the former mill area. Contaminated materials at the Maybell processing site include the tailings pile, which has an average depth of 20 feet (ft) (6 meters [m]) and contains 2.8 million cubic yards (yd{sup 3}) (2.1 million cubic meters [m{sup 3}]) of tailings. The former mill processing area is on the north side of the site and contains 20,000 yd{sup 3} (15,000 m{sup 3}) of contaminated demolition debris. Off-pile contamination is present and includes areas adjacent to the tailings pile, as well as contamination dispersed by wind and surface water flow. The ...
Thermal (gas) nitridation of stainless steels can yield low interfacial contact resistance (ICR), electrically-conductive and corrosion-resistant nitride containing surfaces (Cr2N, CrN, TiN, V2N, VN, etc) of interest for fuel cells, batteries, and sensors. This paper presents the results of scale up studies to determine the feasibility of extending the nitridation approach to thin 0.1 mm stainless steel alloy foils for proton exchange membrane fuel cell (PEMFC) bipolar plates. A major emphasis was placed on selection of alloy foil composition and nitidation conditions potentially capable of meeting the stringent cost goals for automotive PEMFC applications. Developmental Fe-20Cr-4V alloy and type 2205 stainless steel foils were treated by pre-oxidation and nitridation to form low-ICR, corrosion-resistant surfaces. Promising behavior was observed under simulated aggressive anode- and cathode- side bipolar plate conditions ...
Twenty autopsy cases with 2009 pandemic influenza A (2009 H1N1) virus infection, performed between August 2009 and February 2010, were histopathologically analyzed. Hematoxylin-eosin staining, immunohistochemistry for type A influenza nucleoprotein antigen, and real-time reverse transcription-PCR assay for viral RNA were performed on formalin-fixed and paraffin-embedded specimens. In addition, the D222G amino acid substitution in influenza virus hemagglutinin, which binds to specific cell receptors, was analyzed in formalin-fixed and paraffin-embedded trachea and lung sections by direct sequencing of PCR-amplified products. There were several histopathological patterns in the lung according to the most remarkable findings in each case: acute diffuse alveolar damage (DAD) with a hyaline membrane (four cases), organized DAD (one case), acute massive intra-alveolar edema with variable degrees of hemorrhage (three cases), neutrophilic bronchopneumonia (five cases) and ...
Large-scale field tracer experiments have been conducted on Ulchin, Wolsung and Daeduk sites for the purpose of validating FADAS and of analyzing the environmental characteristics around the nuclear sites. The most influential factor in atmospheric dispersion is the meteorological condition. During the experiment, meteorological data were measured on the release point and the selected positions among sampling points. Once radioactive materials are released to the atmosphere, members of public may be exposed through the environmental media such as air, soil and foods. Therefore, to protect the public, adequate countermeasures should be taken at due time for those exposure pathways. both processes, of justification and optimization are applied to a countermeasure simultaneously for decision-making. The work scope of Biological research for the radiation protection had contained the search of biological microanalytic methods for assessing the health effect by ...
Artificial selection and experimental evolution document natural selection under controlled conditions. Collectively, these techniques are continuing to provide fresh and important insights into the...Full Text Available
The R and D activities of the institute focused on two major projects, ``Molecular and cellular environmental toxicology``, and ``Biophysics of multi-cellular systems``. For assessment of health risks emanating from the uptake of heavy metal compounds, work performed under the first mentioned project studies the formation of allergy-inducing metabolic products from membrane lipids, and the effects of related cellular signaling processes. These studies are accompanied by an approach to quantify and classify the toxicity of environmental organometallic compounds. Another major task is research into the pathogenesis of lung disease induced by dusts, gases, and gas-dust mixtures and the liberation of inflammatory agents by immunological cell reactions (alveolar macrophages). Atomic force microscopy is the tool used to visualize the related dynamic changes in bronchial cells. Studies for detection of the localisation and structure of the Fe-Mo ...
The magnetic properties of a single crystal of SmNiSn with the orthorhombic {epsilon}-TiNiSi-type crystal structure have been investigated by magnetic susceptibility, magnetization and electrical resistivity measurements from 1.5 K to room temperature. Two anomalies have been found in the magnetic susceptibility, indicating an antiferromagnetic phase transition at T{sub N}=9.4 K and a second transition at 4.4 K. A large magnetic anisotropy has been found at low temperatures in the temperature and field dependencies of magnetic susceptibility and magnetization. Below 80 K, the easy axis of the magnetization is the c-axis. At T=2.0 K, the c-axis magnetization curve exhibits metamagnetic-like behavior at H{sub c}=42 kOe and reaches 0.54 emu/g at H=55 kOe, whereas for the a- and b-axis the ...
A study on development of magnetic drive packless valves for commercial purpose showed the results as follows; 1. Study on the radial rays effecting to the permanent magnets -Measurement of the strength of Nd-magnets according to irradiation of radial rays. 2. Effects of temperature on the magnetic driving device -Temperature dependency of the Nd-casting magnets. -Effects of temperature on the heat releasing fins of high-temperature valve. 3. Optimization of torque -Arranging method of permanent magnets -Measuring method and results of torque. 4. Design, manufacture and test for the pressure-resisting structure of magnetic power transmitting device -Calculation and design for the flat circular plates under pressure of the magnetic power transmitting device -Design, manufacture and test for the pressure-resisting ...
180 deg magnet chamber is used in Folded Tandem Ion Accelerator for passage and 180 deg bending of ion beam. The chamber is placed between 180 deg terminal magnet (Electro-magnet), which is used for bending, and analysing the beams. Magnet with a particular magnetic field strength bends ions of only specified mass energy product through a precise path. There is also a space limitation in the direction of magnetic field. Both of them require the magnet chamber to be of a close tolerance. Accuracy of center distance between inlet and outlet port of the magnet chamber has to be at par with the concentricity of high energy and low energy beam line. To achieve this we started the fabrication of magnet chamber by following two methods: a) Circular rolling and bending of rectangular tube for 180 deg sector ...
Tests have recently been performed at Fermilab in order to measure the energy losses due to eddy currents and iron and superconductor magnetization. These measurements were performed on six 1.5m long model magnets and eight 15m long full scale collider dipole magnets. AC losses were measured as a function of ramp rate using sawtooth ramps from 500, to 5000 Amps for both types of magnets, while bipolar studies were additionally performed on some of the short magnets. The measured magnet voltage and current for a complete cycle are digitally integrated to yield the energy loss per cycle. Measurement reproducibility is typically 5%, with good agreement between long magnet measurements and extrapolations from short magnet measurement results. Magnetization loss measurements among similar ...
Testing was performed to determine the feasibility and processing characteristics of evaporation of actual Defense Waste Processing Facility (DWPF) recycle material. Samples of the Off Gas Condensate Tank (OGCT) and Slurry Mix Evaporator Condensate Tank (SMECT) were transferred from DWPF to the Savannah River National Lab (SRNL) Shielded Cells and blended with De-Ionized (DI) water and a small amount of Slurry Mix Evaporator (SME) product. A total of 3000 mL of this feed was concentrated to approximately 90 mL during a semi-batch evaporation test of approximately 17 hours. One interruption occurred during the run when the feed tube developed a split and was replaced. Samples of the resulting condensate and concentrate were collected and analyzed. The resulting analysis of the condensate was compared to the Waste Acceptance Criteria (WAC) limits for the F/H Effluent Treatment Plant (ETP). Results from the test were compared to previous testing using simulants and ...
We studied telomeric DNA in leukemic cells as well as in normal T cells, B cells, monocytes, polymorphonuclear leukocytes, and bone marrow hematopoietic progenitor cells. No marked differences were...Full Text Available
Main topic of the project was the manufacturing of highly efficient GaAs-solar cells and the fabrication of concentrator cells. During this process significant progress was made with the material preparation, the solar cell technology and the material and process characterisation. This succeeded in the following efficiencies: - GaAs solar cell made by MOVPE technology: 22.9% on 4 cm{sup 2} (AM1.5g) - GaAs solar cell made by LPE-ER process: 22.8% on 4 cm{sup 2} (AM1.5g) - GaAs concentrator solar cell made by LPE-ER process: 24.9% at C=100xAM1.5d - GaAs concentrator module with fresnel lenses: Module efficiency 20.1% (under irradiation of 793 W/m{sup 2}). Another main focus was the epitaxy of GaAs on Si substrate. Two different approaches were investigated. Together with the cooperation partner ASE, Heilbronn a selective growth technology was ...
Changes in the phosphate metabolism of the transplanted SCCVII (squamous cell carcinoma VII) tumor were studied before and after irradiation using in vivo [sup 31]P-magnetic resonance spectroscopy (MRS). Phosphocreatine (PCr), [gamma]-, [alpha]-, [beta]-ATP, inorganic phosphate (Pi), phosphomonoester (PME), and phosphodiester (PDE) were detected in [sup 31]P-MR spectra of tumor tissues. The curve fitting method was employed for calculating each peak of [sup 31]P-MR spectra (PCr, [beta]-ATP, Pi, PME, PDE). The values of PCr, PCr/Pi, [beta]-ATP/Pi and pH decreased in proportion to the growth of tumor, whereas that of Pi, PME and PDE increased. But the changes of [beta]-ATP were minimal in degree. Based on the fact that the ratio of PCr/Pi highly correlated with tumor volume and showed the most remarkable change among various parameters, it might be the useful index for the tumor growth. Because the phospholipid metabolite PME was detected in the ...
The effects of a moderate-intensity static magnetic field (SMF) on osteoporosis of the lumbar vertebrae were studied in ovariectomized rats. A small disc magnet (maximum magnetic flux density 180 mT)...Full Text Available
Using the full potential linearized augmented plane wave (FLAPW) method, thickness dependent magnetic anisotropy of ultrathin FeCo alloy films in the range of 1 monolayer (ML) to 5 ML coverage on Pd(0 0 1) surface has been explored. We have found that the FeCo alloy films have close to half metallic state and well-known surface enhancement in thin film magnetism is observed in Fe atom, whereas the Co has rather stable magnetic moment. However, the largest magnetic moment in Fe and Co is found at 1 ML thickness. Interestingly, it has been observed that the interface magnetic moments of Fe and Co are almost the same as those of surface elements. The similar trend exists in orbital magnetic moment. This indicates that the strong hybridization between interface FeCo alloy and Pd gives rise to the large magnetic moment. Theoretically calculated ...
In the present paper the progress of optimization of soft magnetic properties have been studied by applying different experimental techniques (magnetic measurements, electric measurements, X-ray analysis, and high-resolution electron microscopy observation). It has been shown that an increase in magnetic permeability after optimization annealing can be mainly attributed to annealing out of microvoids. (author)
Neutron scattering techniques have been used to measure the static structure and magnetic excitations in amorphous magnets. Sum rules and computer models are used to discuss the relationship between the static disorder and the shape of the excitation spectrum. Polarized beam measurements of chi''(Q,E) are compared to analytical theories and computer calculations for the magnetic excitations in amorphous ferromagnets.
The MOS-technology allows to make tiny electronic lenses for multibeam electron systems. In the paper results of research and principles of designing of tiny magnetic electron lenses are submitted. Electronic lenses with a nonconventional configuration of tiny magnetic circuit and electronic lenses with coincident electric and magnetic fields in nonconventional tiny performance are considered
The influence of rigid-body and differential rotation and of a fine-scale chaotic magnetic field and a poloidal magnetic field on the minimum mass of a main-sequence star is investigated. It is shown that rotation and a magnetic field with an energy equal to 10--20% of the star's gravitational energy increase the minimum mass of a main-sequence star by 1.5--2 times.
Helical dipole magnets are required in a project for the Relativistic Heavy Ion Collider (RHIC) to control and preserve the beam polarization in order to allow the collision of polarized proton beams. Specifications are for low current superconducting magnets with a 100 mm coil aperture and a 4 Tesla field in which the field rotates 360 degrees over a distance of 2.4 meters. A magnet meeting the requirements has been developed that uses a small diameter cable wound into helical grooves machined into a thick-walled aluminum cylinder.
The compound GdPd{sub 2}Si, which is reported to order antiferromagnetically at 13 K, has been investigated by heat capacity and electrical resistivity measurement in the presence of external magnetic fields. In contrast to an earlier report, the zero-field heat capacity and resistivity data indicate two magnetic transitions at 13 and 17 K. The external magnetic field substantially influences the resistivity and heat capacity of the compound around the magnetic ordering temperature. The magnetocaloric effect, which is calculated from in-field heat capacity data, is quite large around the magnetic transition temperature. The magnetoresistance is also large near the magnetic ordering temperature. The metamagnetic transition is observed for 10 kOe magnetic field both in magnetocaloric and in magnetoresistance data. The metamagnetic transition ...
The compound GdPd_2Si, which is reported to order antiferromagnetically at 13 K, has been investigated by heat capacity and electrical resistivity measurement in the presence of external magnetic fields. In contrast to an earlier report, the zero-field heat capacity and resistivity data indicate two magnetic transitions at 13 and 17 K. The external magnetic field substantially influences the resistivity and heat capacity of the compound around the magnetic ordering temperature. The magnetocaloric effect, which is calculated from in-field heat capacity data, is quite large around the magnetic transition temperature. The magnetoresistance is also large near the magnetic ordering temperature. The metamagnetic transition is observed for 10 kOe magnetic field both in magnetocaloric and in magnetoresistance data. The metamagnetic transition ...
This paper reports that only a few years ago superconducting magnetic separation was viewed as the next major market for superconducting magnets. The first commercial units had been installed, worked flawlessly, and demonstrated real economic viability. The potential market was seen as quite large, and many people believed that superconducting magnetic separation would soon show the same rapid growth that MRI had demonstrated after its initial success. These hopes even prompted IGC, one of the top MRI magnet builders, to form a separate division devoted to magnetic separation. Despite the existence of Magstream, IGC has not been overly active in the market. As a technology that has applications from the clay on the Earth to the soil on the moon, superconducting magnetic separation has yet to become widely used.
The characteristics of the local magnetic shear, a quantity associated with high-mode-number ballooning mode stability, are considered in heliotron/torsatron devices that have a large Shafranov shift. The local magnetic shear is shown to vanish even in the stellarator-like region in which the global magnetic shear is positive. The reason for this is that the degree of the local compression of the poloidal magnetic field on the outer side of the torus, which maintains the toroidal force balance, is reduced in the stellarator-like region of global magnetic shear because the global rotational transform in heliotron/torsatron systems is a radially increasing function. This vanishing of the local magnetic shear is a universal property in heliotron/torsatron systems with a large Shafranov shift since it results from toroidal force balance in the stellarator-like ...
We have analyzed the MHD flow of a conducting couple stress fluid in a slit channel with rhythmically contracting walls. In this analysis we are taking into account the induced magnetic field. Analytical expressions for the stream function, the magnetic force function, the axial pressure gradient, the axial induced magnetic field and the distribution of the current density across the channel are obtained using long wavelength approximation. The results for the pressure rise, the frictional force per wave length, the axial induced magnetic field and distribution of the current density across the channel have been computed numerically and the results were studied for various values of the physical parameters of interest, such as the couple stress parameter ?, the Hartmann number M, the magnetic Reynolds number R and the time averaged mean flow rate ?. Contour plots for the stream and ...
We compare experimental data for temperature dependence of the magnetic order parameter and the magnetic excitations (spin waves) in materials with a quenched orbital moment and a well-defined spin quantum number. It is observed that the thermal decrease of the two quantities proceeds according to the same analytical function of the type y(T)=1-cT"#epsilon# with an identical exponent #epsilon#. This power function applies not only asymptotically for T->0 but holds over a wide temperature range. The exponent #epsilon# is universal, i.e. independent of spin order type and lattice symmetry and depends only on the dimensionality of the relevant interactions and on whether the spin quantum number is integer or half-integer. The different T"#epsilon# functions are identified as representations of stable universality classes. The fact that order parameter and magnetic excitations follow the same T"#epsilon# function shows that ...
The aim of the paper is to review the role of interventional radiology in the management of hemodialysis vascular access and complications in renal transplantation. The evaluation of patients with hemodialysis vascular access is complex. It includes the radiology/ultrasound (US) evaluation of the peripheral veins of the upper extremities with venous mapping and the evaluation of the central vein prior to the access placement and radiological detection and treatment of the stenosis and thrombosis in misfunctional dialysis fistulas. Preoperative screening enables the identification of a suitable vessel to create a hemodynamically-sound dialysis fistula. Clinical and radiological detection of the hemodynamically significant stenosis or occlusion demands fistulography and endovascular treatment. Endovascular prophylactic dilatation of stenosis greater than 50% with associated clinical abnormalities such as flow-rate reduction is warranted to prolong access patency. The technical success ...
Many epidemiological studies have investigated residential exposure to extremely-low-frequency magnetic field (ELF-MF) for children, but exposure at schools where children may stay up to 8 h every weekday was rarely considered. Between March and June 2004, we carried out a field study in Taipei City and County of northern Taiwan to explore ELF-MF exposure pattern among children at schools with high voltage transmission lines (HVTL) running through the campuses. One hundred and one children attending 14 schools with nearby HVTL (exposed group) and 123 children of 18 schools at least 100 m away from HVTL (unexposed group) were monitored for 24-hour personal ELF-MF exposure. Selected classrooms and playgrounds within the buffer regions (i.e., within 30 m of HVTL) and those away from the buffer regions were also assessed, using spot measurements, to determine the extent to which HVTL may contribute to the environmental exposure on campuses. Results ...
Development of techniques for separating isomeric nuclides is important to the investigation of schemes for gamma-ray lasers. In preparation for an experiment to separate 10_1_4 atoms of the /sub 197m/Hg (299 keV, tau/sub 1/2/ = 24 hours) isomer, we report isotopically selective resonance ionization of mercury atoms. This has been accomplished by three-step excitation via the 6_3P"1 and 8_1S"0 excited states, using three collinear pulsed laser beams of 254, 286, and 532 nm wavelengths from a Nd:YAG and two dye lasers. These beams were passed through a closed mercury-vapor cell containing electrostatic plates to which the ions were drawn. Ion current and fluorescent radiation were measured as a function of laser frequency. Hyperfine structures for the 254- and 286-nm transitions were observed.
A conjugate of 6-hydrazinopyridine-3-carboxylic acid (HYNIC) with the amino analogue of metronidazole (MN) was synthesized through a multiple-step reaction. HYNIC-MN could be labeled easily and efficiently with 99mTc using N-(2-hydroxy-1,1-bis(hydroxymethyl)ethyl)glycine (tricine) and ethylenediamine -N,N?-diacetic acid (EDDA) as coligands to form the 99mTc?HYNIC?MN complex in high yield (>95%). Its partition coefficient indicated that it was a good hydrophilic complex. The tumor cell experiment showed that the 99mTc?HYNIC?MN complex had a certain hypoxic selectivity. The biodistribution studies of 99mTc?HYNIC?MN in Kunming mice bearing S180 tumor showed a favorable tissue distribution profile with high tumor uptake, and low or negligible accumulation in non-target organs, suggesting 99mTc...
Current bioartificial extra-corporeal systems are bioreactors where cells are separated from the surrounding media by porous polymeric membranes. The present work focuses on the design of membranes that allow the differential diffusion of plasma metabolites and proteins such as immunoglobulin (IgG). This design will improve catabolites removal and reduce possible immune response and virus infection. We demonstrate the feasibility to synthesize the hydrogels confined to the macroporous structure of membranes by radiation-induced in situ polymerization. The hollow-fiber membranes were soaked in aqueous monomeric solution, rinsed and irradiated while submerged in oil. This procedure confined the hydrogel to the void internal volume of the pores of the membrane. Hydrogels of polyacrylamide and polyHEMA were synthesized this way by irradiation at 10 kGy. Hydraulic permeability and diffusion of glucose, albumin and IgG were measured in these hydrogel-filled membranes. ...
The atomic explosions in Hiroshima and Nagasaki made the name radiation itself become a nightmare. Notwithstanding this, radiation continued to serve the mankind specially in diagnosis of several human diseases and in the treatment of intractable malignancies. With their latest research tools biologists have now shown a significant shift in the earlier paradigm; even the concept that radiation initiates cancer appears to be no longer tenable. On the contrary, selective radiation doses inhibit growth of cancer cells and radiation in combination with many chemotherapeutic drugs, radiosensitizing chemicals and/or hyperthermia, is emerging as a new modality for cancer treatment which offers high therapeutic advantages. In addition, the deleterious effects of radiation can now be strategically counter poised by the use of many drugs and chemicals. This has been possible by the newer insights gained in the mechanism of biological effects of ...
To analyze and review the most common focal lesions of the external auditory canal (EAC), describing the computed tomography (CT) findings. The CT images of EAC were reviewed in a series of 167 patients. Abnormal findings were recorded in 13 cases. The CT images were correlated with otoscopic and/or intraoperative findings. There were four cases of osteoma (one located outside the EAC); all of which were treated surgically, as was the one case of exostosis. Six patients presented debris in EAC, coinciding with clinical evidence of external otitis. There were two cholesteatomas derived from EAC, one of them secondary to survery to treat osteoma. On patient was diagnosed as having a basal cell carcinoma of the ear, extending to EAC, but refused to undergo surgery. Five patients presented small triangular laminae of dense bone arising from the upper wall of the EAC which were defined as abnormal variants of the fusion of the temporal squamous epithelium to the ...
Cu/YSZ cermet (40 and 60 vol.% Cu powder with balance YSZ) is a more economical cathode material than the conventional Ni/YSZ cermet for high temperature electrolysis (HTE) of water vapor and it was successfully fabricated by high-energy ball-milling of Cu and YSZ powders, pressing into pellets (o 13 mm x 2 mm) and subsequent sintering process at 700 deg. C under flowing 5%-H{sub 2}/Ar gas. The Cu/YSZ composite material thus fabricated was characterized using various analytical tools such as XRD, SEM, and laser diffraction and scattering method. Electrical conductivity of sintered Cu/YSZ cermet pellets thus fabricated was measured by using 4-probe technique for comparison with that of conventional Ni/YSZ cermets. The effect of composite composition on the electrical conductivity was investigated and a marked increase in electrical conductivity for copper contents greater than 40 vol.% in the composite was explained by percolation threshold. Also, Cu/YSZ cermet was ...
Options for successfully using biogas depend on project scale. Almost all biogas from anaerobic digesters must first go through a gas handling system that pressurizes, meters, and filters the biogas. Additional treatment, including hydrogen sulfide-mercaptan scrubbing, gas drying, and carbon dioxide removal may be necessary for specialized uses, but these are complex and expensive processes. Thus, they can be justified only for large-scale projects that require high-quality biogas. Small-scale projects (less than 65 cfm) generally use biogas (as produced) as a boiler fuel or for fueling internal combustion engine-generators to produce electricity. If engines or boilers are selected properly, there should be no need to remove hydrogen sulfide. Small-scale combustion turbines, steam turbines, and fuel cells are not used because of their technical complexity and high capital cost. Biogas cleanup to pipeline or transportation fuel specifications is ...
In this paper a computational analysis of 11 fuel samples (seven UO_2 and four MOX) with a burn-up ranging from 20 MWd/kgHM up to 121 MWd/kgHM (HM: Heavy Metal) is carried out with the depletion module of the lattice code CASMO-4E [Rhod01, Rhod01b] using the neutron data libraries ENDF/B-VI and JEF-2.2 and a pin cell model. In order to assess the accuracy of the model and the depletion calculation in the determination of the isotopic inventory after several irradiation cycles, the calculated results were compared to experimental data gathered from a chemical isotopic analysis of the fuel samples performed at the Hot Laboratory at the Paul Scherrer Institut (PSI), Switzerland. Selected results of this comparison, which includes 54 isotopes (17 actinides and 37 fission products), are presented here. (orig.)
Research and experimental development comprise innovative and creative work undertaken systematically to increase the stock of knowledge of science, engineering, and society. This knowledge reserve is used to improve living conditions and standards, including economic growth. Research and development (R&D) expenditures are useful measures of the scale and direction of technological innovation within a country, industry, or scientific field. Administrators concerned with economic growth and performance rely on R&D statistics as one possible type of indicator of technological change. R&D statistics are an essential tool in many government programs and evaluations (OECD 1993). The objective of the analysis was to identify and evaluate R&D funding sources, levels, and trends in the energy sectors of selected industrialized countries (Australia, Belgium, Canada, Denmark, Finland, France, Germany, Italy, Japan, Netherlands, Norway, Sweden, Switzerland, ...
A comprehensive and highly selective method for detecting in bacterial supernatants a modified sulfur nucleoside, S-adenosyl-L-methionine (SAM), and its metabolites, i.e., S-adenosylhomocysteine (SAH), adenosine (Ado), 5prime-deoxy-5prime-methylthioadenosine (MTA), adenine (Ade), S-adenosyl-methioninamine (dcSAM), homocysteine (Hcy) and methionine (Met), was developed. The method is based on reversed-phase liquid chromatography with positive electrospray ionization (ESI+) coupled to a hybrid linear quadrupole ion trap (LTQ) and 7-T Fourier transform ion cyclotron resonance mass spectrometry (FTICRMS). A gradient elution was employed with a binary solvent of 0.05 M ammonium formate at pH 4 and acetonitrile. The assay involves a simultaneous cleanup of cell-free bacterial broths by solid-pha...
Evolutionary theory holds that aging is a consequence of the declining force of natural selection with age. We discuss here the evidence that among the causes of aging in complex multicellular organisms, such as mammals, is the antagonistically pleiotropic effects of the cellular responses that protect the organism from cancer. Cancer is relatively rare in young mammals, owing in large measure to the activity of tumor suppressor mechanisms. These mechanisms either protect the genome from damage and/or mutations, or they elicit cellular responses--apoptosis or senescence--that eliminate or prevent the proliferation of somatic cells at risk for neoplastic transformation.We focus here on the senescence response, reviewing its causes, regulation and effects. In addition, we describe recent data that support the idea that both senescence and apoptosis may indeed be the double-edged swords predicted by the evolutionary hypothesis of antagonistic ...
Purified protein kinase C (C-kinase) from guinea pig pancreas and rat brain stimulated adenylate cyclase activity in purified rat adipocyte membranes. Cyclase stimulation occurred over 100 to 1000 mU/ml of C-kinase activity, required greater than 10 ..mu..M calcium, proceeded without a lag, was not readily reversible, and required no exogenous phospholipid. Moreover, C-kinase inhibitors, such as chlorpromazine and palmitoyl carnitine, inhibited selectively adenylate cyclase which was activated by C-kinase and calcium. Depending on assay conditions, 10 nM 12-0-tetradecanoylphorbol-13-acetate (TPA) either enhanced or was required for kinase action on cyclase. Also, TPA plus calcium promoted the quantitative association of C-kinase with membranes. Adenylate cyclase activation by C-kinase was seen both in the presence and absence of exogenous GTP, indicating that the kinase effect does not result from an action on the GTP-binding, inhibitory regulatory component (N/sub ...
A system is claimed for multiplexing or demultiplexing pulsed laser radiation having an acousto-optical device which is electrically controlled to switch a common path of high pulse rate laser radiation between a plurality of spatially distinct paths for relatively lower pulse rate laser radiation at which the pulses are sequenced according to a predetermined time pattern. The acousto-optical element typically includes a Bragg cell which is electrically driven by a set of distinct frequencies, causing deflection of radiation passing therethrough at a predetermined set of angles whereby pulsed radiation on a single path may be distributed onto the plural separate paths or radiation on plural separate paths of time-sequenced pulses of radiation can be combined into a single path of augmented pulse rate. The control of the acousto-optical element may be provided by selectively switching the output of a plurality of fixed frequency oscillators of ...
We describe a class of organic molecular magnets based on zwitterionic molecules (betaine derivatives) possessing donor, p bridge, and acceptor groups. Using extensive electronic structure calculations we show the electronic ground-state in these systems is magnetic. In addition, we show that the large energy differences computed for the various magnetic states indicate a high Neel temperature. The quantum mechanical nature of the magnetic properties originates from the conjugated p bridge (only p electrons) in cooperation with the molecular donor-acceptor character. The exchange interactions between electron spin are strong, local, and independent on the length of the p bridge.
We discuss how magnetic phenomena affect superconductivity in simple metals, transition metals and alloys thereof, and dilute Rare-Earth alloys. It is shown both qualitatively and quantitatively that superconductors are sensitive probes for studying itinerant spin excitations, local spin excitations associated with nearly magnetic impurities, the effect of the atomic environment on the stability of local magnetic moments, and the nature of the spin order in Rare-Earth alloys. Also, we discuss how magnetic impurities can be used to study the electronic configuration which is responsible for superconductivity in Laves-phase crystals like A-15 compounds and ..beta..-W crystals, for example.
The magnetization of ultrathin bcc Fe films (two and three monolayers) on MgO was measured and compared with the behavior predicted for a two-dimensional ferromagnet. The experiment indicated that no hysteresis was present in the magnetization. Instead, the magnetization at low temperature was affected by a marked field cooling effect. These observations lead to the conclusion that films of Fe on MgO of such thickness exhibit superparamagnetic behavior as if they were not entirely continuous. In contrast, films thicker than five monolayers exhibit a magnetic response close to that of bulk iron.
It has been carried out the magnetic properties determination for high iron oxide content glasses series obtained from a geothite red mud waste from the zinc hydrometallurgy and dolomite and glass cullet as main raw materials. It has been determined the magnetic susceptibility and magnetization values for the glasses here investigated. The results suggest that the magnetic behaviour are depending on the glass chemical composition, so that glasses can be differently classified like ferrimagnetic, ferromagnetic, superparamagnetic and paramagnetic. (Author) 6 refs.
Magnetic fluctuations present in the paramagnetic Mn{sub 0.81}Ni{sub 0.19} system have been investigated by measuring inelastic magnetic neutron scattering from a single crystal at temperatures of 450, 585 and 700 K. Antiferromagnetic correlations are observed to be present at all the temperatures studied. The spectral width of the magnetic scattering has been observed to increase with temperature, while the spatial range of the magnetic correlations is seen to decrease as the temperature is raised. The wave-vector-dependent susceptibility is found to follow a Curie-Weiss law near the (1 0 0) position, in agreement with theoretical predictions.
It is suggested that the magnetic Ap stars can be rotationally decelerated to long periods by the braking action of the associated magnetic field on time scales of order 10"7--10"1"0 years depending on whether the star's dipole field is aligned perpendicular or parallel to the rotation axis. Rotation includes a toroidal magnetic field in the plasma surrounding a star, and the accompanying magnetic stresses produce a net torque acting to despin the star. These results indicate that it is not necessary to postulate mass loss or mass accretion for this purely hydromagnetic braking effect.
The homogeneity of the magnetic field in the LHC dipoles strongly depends on the correct position of the superconducting cables: this is related to the quality of the dipole components, such as the dimension of the coil spacers (copper wedges), of the cable and of the collars. The performance in operational conditions is also affected by the magnetization of the cables. In this work, we analyse the measurements of these quantities during the production of the 1276 LHC dipoles, their trends, and the relation to the measured magnetic field. A novel mtehod to locate electrical shorts based on the analysis of magnetic measurements is also presented, and applications to 15 dipoles reascued during the production is given.
As low temperature cryocoolers become more frequently used to cool superconducting magnets, it becomes increasingly apparent that the connection between the cooler and the magnet has an effect on the design and performance of the magnet. In general, the use of small coolers can be considered in two different temperature ranges; (1) from 3.8 to 4.8 K for magnet fabricated with LTS conductor and (2) from 18 to 35 K for magnets fabricated using HTS conductor. In general, both temperature ranges call for the use of a two-stage cooler. The best method for connecting a cooler to the magnet depends on a number of factors. The factors include: (1) whether the cooler must be used to cool down the magnet from room temperature, (2) whether the magnet must have one or more reservoirs of liquid cryogen to keep the ...
Anisotropic Nd{endash}Fe{endash}B magnet powders can be produced by the hydrogenationdecomposition-desorption-recombination (HDDR) process from Nd{endash}Fe@ xnB{endash}Co{endash}M ({ital M}=Ga, Zr, Nb, Hf, and Ta) alloys. The present status of those HDDR powders and the bonded magnets made from them are reviewed with regards to the powder particle size dependence of their magnetic properties, their magnetic thermal stability, and their magnetization behavior. The results of a mechanistic study on the recombination step are also presented. The magnetic properties of the anisotropic HDDR powder depend relatively little on the powder particle size. Bonded magnets with a density of {approximately}6.20 g/cm{sup 3} and a BH{sub max} of 18.5{endash}20.5 MGOe can be produced from anisotropic HDDR powders with particle sizes of below 300 {mu}m diam. ...
We have investigated the properties of nerve cell precursors in hydra by analyzing the differentiation and proliferation capacity of interstitial cells in the peduncle of Hydra oligactis, which is a region of active nerve cell differentiation. Our results indicate that about 50% of the interstitial cells in the peduncle can grow rapidly and also give rise to nematocyte precursors when transplanted into a gastric environment. If these cells were committed nerve cell precursors, one would not expect them to differentiate into nematocytes nor to proliferate apparently without limit. Therefore we conclude that cycling interstitial cells in peduncles are not intermediates in the nerve cell differentiation pathway but are stem cells. The remaining interstitial cells in the peduncle are ...
The stunning, intricate interaction between the visual, vestibular and optomotor systems--each a miracle on its own--ensures maintenance of orientation in space as well as visual recognition and target selection despite a host of sensory conflicts and adversary disturbances. Their main goals are to keep a target of interest on the fovea by either maintaining or shifting the direction of gaze in order to produce an accurate internal representation of the visual surroundings, in particular the selected target, and to continuously mirror the spatial relationship between these various visual elements and the self. Not surprising, the implementation of this host of elaborate neural networks encompasses almost every part of the brain, including the brainstem, cerebellum, extrapyramidal system and many areas of the cerebral cortex. Thus far, these systems are among the best investigated in brain research; and enormous knowledge was amassed over the ...
Objective: To assess dynamic MRI with Gd-DTPA enhancement for evaluating inflammatory changes in the subacromial bursa. Design and patients: We detected the signal intensity changes in dynamic MRI of the subacromial bursa, and confirmed these macroscopically by arthroscopy and histologically. The signal intensity was measured using built-in software, and the enhancement ratio (E ratio) was calculated from dynamic MR images. In addition, as a parameter of the rate of the increase in the signal intensity from 0 to 80 s, the mean increase per second in the E ratio was obtained as the coefficient of enhancement (CE). The correlation was studied of the E ratio and CE with the arthroscopic findings (redness, villous formation, thickening and adhesion), and of the E ratio and CE with the histological findings (capillary proliferation, papillary hyperplasia, fibrosis and inflammatory cell infiltration) of the subacromial bursa. Of patients with shoulder pain, this study ...
Several examples of agonist-directed trafficking of receptor signalling at 5-HT2A and 5-HT2C receptors have been reported that involve independent downstream transduction pathways. We now report the functional selectivity of a series of chemically diverse agonists at human (h)5-HT2A, h5-HT2B and h5-HT2C-VSV by examining two related responses, the upstream activation of Gq/11 proteins in comparison with its associated cascade of calcium mobilisation. At the h5-HT2A receptor, d-lysergic acid diethylamide (LSD) and the antiparkinsonian agents lisuride, bromocriptine and pergolide exhibit a higher potency for Gq/11 activation than calcium release in contrast with all the other tested ligands such as 5-HT, mCPP and BW723C86, that show an opposite preference of signalling pathway. Comparable observations are made at h5-HT2B and h5-HT2C-VSV receptors, suggesting a similar mechanism of functional selectivity for the three serotonin receptors. ...
A silicon solar cell assembly comprising a large, thin silicon solar cell bonded to a metal mount for use when there exists a mismatch in the thermal expansivities of the device and the mount.
Experiments were designed to elucidate whether or not the irradiated bone marrow cells receive any stimulation for the self-replication and differentiation from normal 'stromal' cell colonies in the bone marrow cell culture in vitro. When irradiated or unirradiated bone marrow cells were overlaid on the normal adherent cell colonies, the proliferation of haemopoietic stem cells was supported, the degree of the stimulation depending on the starting cellular concentration. There was, however, no significant changes in the concentration of either CFUs or CFUc regardless of the dose of irradiation on the bone marrow cells overlaid. This was a great contrast to the dose-dependent decrease of CFUs or CFUc within the culture in which both the stem cells and stromal cells were ...
Ethane oxidation was studied in ethane-grown resting cells (mycelia) of an Acremonium sp. and in cell-free preparations of such mycelia. From resting cell experiments evidence was found for a pathway...Full Text Available
In most adult tissues there reside pools of stem and progenitor cells inside specialized microenvironments referred to as niches. The niche protects the stem cells from inappropriate expansion...Full Text Available
... Fuel Cell Technologies Equipment on Environmental Expert Find and compare a variety of fuel cell technologies equipment on the world's largest environmental industry portal. View ...
Purpose.There is a paucity of neuron replacement studies for retinal ganglion cells. Given the complex phenotype of these neurons, replacement of ganglion cells may be impossible....Full Text Available
Cell cultures were prepared from lung tumors occurring in beagles following exposure to inhaled plutonium. Morphologic and growth characteristics of two of these cell lines are described.
We report the isolation of adherent, clonogenic, fibroblast-like cells with osteogenic and adipogenic potential from the blood of four mammalian species. These cells phenotypically resemble but are...Full Text Available
Effects of cell concentrations on the survival and repopulation of haemopoietic stem cells after irradiation were studied in the long-term culture of mouse bone marrow cells in vitro. No difference was observed in the survival of the stem cells among cultures in which 0 - 10/sup 7/ cells were re-inoculated on the adherent cell colonies in the culture flask. Stem cells showed a significant proliferation within 1 week and the number of the stem cells exceeded the control in 3 weeks after irradiation in the cultures with less than 10/sup 6/ re-inoculated cells per flask. In contrast, there was a considerable delay in the onset of stem cell proliferation after irradiation in the culture with 10/sup 7/ cells per flask. Based on these results, a possibility that a ...
Measurements of the magnetic susceptibility betweeen 0.03 and 300 K and of the magnetization between 0.05 and 10 K for magnetic fields up to 60kOe have been used to investigate effects from the interaction between the conduction electrons and local magnetic moments in (Lasub(1-x)Cesub(x))B_6 alloys (0.0007<=x<=0.10). For Ce concentrations x<0.006 the data show Kondo-type single impurity behaviour at low temperatures with a transition from a magnetic to a non-magnetic regime of the Ce ions. In the magnetic regime the impurity susceptibility follows a Curie-Weiss law, and in the non-magnetic regime it varies with T"2. An external magnetic field gradually restores the free-ion behaviour of the Ce impurities. For more concentrated alloys interactions between the impurities are observed. The RKKY ...
Magnetic drug targeting, using core-shell magnetic carrier particles loaded with anti-cancer drugs, is an emerging and significant method of cancer treatment. Gold shell-iron core nanoparticles (Fe@Au) were synthesized by the reverse micelle method with aqueous reactants, surfactant, co-surfactant and oil phase. XRD, XPS, TEM and magnetic property measurements were utilized to characterize these core-shell nanoparticles. Magnetic measurements showed that the particles were superparamagnetic at room temperature and that the saturation magnetization decreased with increasing gold concentration. The anti-cancer drug doxorubicin (DOX) was loaded onto these Fe@Au nanoparticle carriers and the drug release profiles showed that upto 25% of adsorbed drug was released in 80 h. It was found that the amine (-NH2) group of DOX binds to the gold shell. An in vitro apparatus simulating the human ...
With "1"5"1Eu-Moessbauer spectroscopy and other methods the complex magnetic properties of Eu_2PdSi_3, arising from the two crystallographically different lattice sites of the Eu"2"+ ions, have been already studied. Here we study the impact of magnetic dilution of the magnetic Eu"2"+ sites by non-magnetic Y"3"+ ions. A previous specific heat study has found reduced magnetic ordering temperatures with strong indication of disorder effects like in magnetic spin glasses. Here we provide from "1"5"1Eu-Moessbauer spectroscopy detailed information of the impact of Y"3"+ substitution on the magnetic properties of the two lattice sites, well distinguishable in the "1"5"1Eu-spectra. Since the substitution of the larger Eu"2"+ ions by the smaller Y"3"+ ions is connected with a lattice contraction, we also applied high pressure to the Eu_2PdSi_3 sample ...
Although the p53 tumor suppressor is relatively well characterized, much less is known about the functions of other members of the p53 family, p73 and p63. Here, we present evidence that in specific pathological conditions caused by exposure of normal cells to bile acids in acidic conditions, p73 protein plays the predominant role in the DNA damage response. These pathological conditions frequently occur during gastric reflux in the human esophagus and are associated with progression to esophageal adenocarcinoma. We found that despite strong DNA damage induced by bile acid exposure, only p73 (but not p53 and p63) is selectively activated in a c-Abl kinase-dependent manner. The activated p73 protein induces DNA damage repair. Using a human DNA repair PCR array, we identified multiple DNA repair genes affected by p73. Two glycosylases involved in base excision repair, SMUG1 and MUTYH, were characterized and found to be transcriptionally regulated ...
The laser grooved buried grid (LGBG) cell was developed at the University of New South Wales, Australia. The enormous advantage of the Saturn technology is the simple formation of a selective emitter via two step diffusion, which is optimised on the surface for the charge carrier generation and under the metal grid for contact formation. The reflection losses due to shading are simultaneously minimised by the installation of the contacts at right angles in the wafer surface. Due to the increased infeed compensation, particularly the compensation covering the costs, the economic importance of the energy yield of a PV plant is growing. Ultimately, it is not just the installed output (KWp) that matters to the customer, but increasingly the specific yield (kWh/kWp). An increased energy yield with optimally matched components with the Saturn technology means high annual compensation, which in turn shortens the amortisation period. [Deutsch] Die ...
Scrotal skin of black Long-Evans rats and human thigh skin were maintained in vitro as organ cultures for as long as 14 days, and examined histologically using the combined skin splitting and Dopa techniques. Selected rat skin cultures received testosterone in the culture medium and/or were irradiated with ultraviolet light (290 to 320 nm uvl). With increased time in culture, scrotal melanocytes round up and there is an increase in epidermal pigmentation. Human skin behaves similarly; after eight days in vitro human melanocytes also become rounded, but remain strongly Dopa-positive. Addition of exogenous testosterone to cultured rat skin maintains dendritic morphology of melanocytes, but cell body size is still reduced. uvl irradiation stimulates melanocytes in rat skin cultures, maintaining their dendritic morphology and increasing epidermal and dermal pigmentation. Cultured skin receiving both uvl and testosterone illustrates a synergistic ...
Statoil is operating an increasing number of offshore and onshore pipelines in the North Sea area and elsewhere. Cathodic protection is a significant part of the corrosion management for these lines and we have collected a significant amount of experience with respect to design and operation of the systems. This paper deals with our comprehensive program for the onshore cathodic protection systems and the various challenges in different countries with respect to technical matters, such as operating conditions and different terrain. Generally, the systems are based on automatically controlled rectifier systems with a wide range of current drainage and very comprehensive monitoring of potentials and current flowing. The use of coupons, polarisation cells and buried reference cells are essential, as well as the use of intensive measurements along the route. The use of online monitoring of selected test posts and all rectifier ...
Fourier transform infrared absorption spectroscopy has been used for the determination of the line strengths of 41 CO and CO[sub 2] absorption lines at temperatures between 295 and 1250 K. The CO vibrational-rotational lines were from the [ital P] branch of the fundamental absorption band (2150--1950 cm[sup [minus]1]) while the CO[sub 2] vibrational-rotational lines were from the far wing of the [ital R] branch of the [nu][sub 3] fundamental band (2395--2380 cm[sup [minus]1]). The intensities of the lines were measured from absorption spectra recorded in a high-temperature gas cell containing known concentrations of CO/CO[sub 2]/N[sub 2] gas mixtures at atmospheric pressure. Absorption spectra were recorded through the cell with the use of a moderate-resolution Fourier transform infrared spectrometer. The absorption spectra were mathematically corrected for distortions resulting from the finite resolution of the spectrometer and for peak ...
Fourier transform infrared absorption spectroscopy has been used for the determination of the line strengths of 41 CO and CO_2 absorption lines at temperatures between 295 and 1250 K. The CO vibrational-rotational lines were from the P branch of the fundamental absorption band (2150--1950 cm"-"1) while the CO_2 vibrational-rotational lines were from the far wing of the R branch of the #nu#_3 fundamental band (2395--2380 cm"-"1). The intensities of the lines were measured from absorption spectra recorded in a high-temperature gas cell containing known concentrations of CO/CO_2/N_2 gas mixtures at atmospheric pressure. Absorption spectra were recorded through the cell with the use of a moderate-resolution Fourier transform infrared spectrometer. The absorption spectra were mathematically corrected for distortions resulting from the finite resolution of the spectrometer and for peak overlap. Line strength measurements were made from the corrected ...
The goal of the present work was to determine the impact of N3-methyladenine (3-mA), an important lesion generated by many environmental agents and anticancer drugs, on in vivo DNA replication and in vitro RNA transcription. Due to 3-mA chemical instability, the stable isostere 3-methyl-3-deazaadenine (3-m-c(3)A) was site specifically positioned into an oligodeoxynucleotide. The oligomer was, then incorporated into a vector system that is rapidly converted to ssDNA inside yeast cells and requires DNA replication opposite the lesion for plasmid clonal selection. For control purposes, an adenine or a stable apurinic/apyrimidinic (AP)-lesion was placed at the same site. The presence of each lesion in the oligonucleotide was confirmed by MALDI-TOF analysis. Plasmids were then transfected into yeast cells. While the AP-site dramatically reduced plasmid replication in all strains, the 3-m-c(3)A had a slight effect in the rad30 ...
Proton magnetic resonance spectroscopy (MRS) measures concentrations of metabolites in vivo and provides a powerful method for identifying tumours. MRS has not entered routine clinical use partly due to the difficulty of analysing the spectra. To create a straightforward method for interpreting short-echo-time MRS of childhood cerebellar tumours. Single-voxel MRS (1.5-T Siemens Symphony NUM4, TR/TE 1,500/30 ms) was performed at presentation in 30 children with cerebellar tumours. The MRS results were analysed for comparison with histological diagnosis. Peak heights for N-acetyl aspartate (NAA), creatine (Cr), choline (Cho) and myo-inositol (mIns) were determined and receiver operator characteristic curves used to select ratios that best discriminated between the tumour types. The method was implemented by a group of clinicians and scientists, blinded to the results. A total of 27 MRS studies met the quality control criteria. NAA/Cr >4.0 ...
Airbag pressure vessels for the north-American market mainly are made by forging and by the use of steel alloys. In Europe aluminum alloys are common and the manufacturing process is extrusion of circular blanks - made from cold rolled plates - in a form applying a 100 t press at room temperature. Then by heat treatment the strength/hardness of the material is properly adjusted and after that the pressure vessel parts have to be continuously inspected with an inspection and handling cycle time of 3 s. Inspection of the axis-symmetric parts is asked for surface breaking extrusion defects as well as for surface parallel delaminations in the bulk volume. Furthermore, the material strength is a quality characteristic that has to be nondestructively registered and documented. The inspection is performed by eddy current probes and an EMAT, of which the eddy current impedance measurements are used for surface breaking extrusion defect detection and sizing (single frequency technique with ...
The aim of this study was to determine sensitivity and specificity of magnetic resonance angiography (MRA) for the assessment of durable occlusion of intracranial aneurysms with Guglielmi detachable coils (GDC) and to point out the influence of MRA results in re-intervention strategies. Forty-five patients with 54 aneurysms that were previously treated by endovascular occlusion with GDC were selected for this study. All patients underwent digital subtraction angiography (DSA) and MRA examinations on the same day. The time-of-flight MRA studies were performed on a 1-T scanner. The MRA images were first read by radiologists who were not aware of the DSA results. In a second consensus reading by the neuroradiologists who had performed all interventional procedures of this series, the decision was made as to whether re-treatment was necessary. The distribution of aneurysm sizes, configurations and treatment results were sufficient for an unbiased ...
Laser spectroscopy measurements have been performed on neutron-deficient and stable Ir isotopes using the COMPLIS experimental setup installed at ISOLDE-CERN. The radioactive Ir atoms were obtained from successive decays of a mass-separated Hg beam deposited onto a carbon substrate after deceleration to 1kV and subsequently laser desorbed. A three-color, two-step resonant scheme was used to selectively ionize the desorbed Ir atoms. The hyperfine structure (HFS) and isotope shift (IS) of the first transition of the ionization path 5d"76s"2"4F_9_/_2#->#5d"76s6p"6F_1_1_/_2 at 351.5nm were measured for "1"8"2"-"1"8"9Ir, "1"8"6Ir"m and the stable "1"9"1","1"9"3Ir. The nuclear magnetic moments #mu#_I and the spectroscopic quadrupole moments Q_s were obtained from the HFS spectra and the change of the mean square charge radii from the IS measurements. The sign of #mu#_I was experimentally determined for the first time for the masses 182#=#+0.2 for ...
Studies are made in this program to enhance our understanding of the role of 5f electrons in chemical bonding. Most of our studies on the macroscopic scale emphasize certain isotopes available from the National Transplutonium Production Program centered at HFIR/TRU -namely, _9_6"2"4"8Cm, _9_7"2"4"9Bk, _9_8"2"4"9Cf, _9_9"2"5"3Es, and _9_9"2"5"4Es. Particular classes of compounds, such as hydrides, chalcogenides, and pnictides are often selected for study on the basis of their utility in bringing out significant chemical differences between the lanthanides and the actinides. High temperature/high pressure experiments on actinide metals and compounds reveal characteristics about the degree of 5f electron localization as a function of atomic number in the series. Magnetic properties of metals and compounds are investigated using ultra-sensitive methods and hydration numbers of ions in solution are investigated by neutron scattering at HFIR. As a ...
There is very little known about the long-term evolution of the MHC and MHC-like molecules. This is because both the theory (the evolutionary questions and models) and the practice (the animals systems, functional assays and reagents to identify and characterize these molecules) have been difficult to develop. There is no molecular evidence yet to decide whether vertebrate immune systems (and particularly the MHC molecules) are evolutionarily related to invertebrate allorecognition systems, and the functional evidence can be interpreted either way. Even among the vertebrates, there is great heterogeneity in the quality and quantity of the immune response. The functional evidence for T-lymphocyte function in jawless and cartilagenous fish is poor, while the bony fish seem to have many characteristics of a mammalian immune system. The organization and sequence of fish Ig genes also indicate that important events in the evolution of the immune system and the MHC occurred in the fish, but ...
The electrical resistivity, Hall effect, and magnetic susceptibility of single-crystal UPd_2Si_2 have been studied between 4.2 and 300 K. A large anisotropy was observed in both the magnetic and transport properties. There is a quadratic temperature dependence of the resistivity for a range of temperatures between 4.2 and 80 K. At higher temperatures, the resistivity indicates a Kondo-type behavior. The behavior of these quantities is accounted for by the magnetic phase transitions at 108 and 136 K reported from neutron-scattering studies. At high temperatures, the magnetic susceptibility of UPd_2Si_2 is Curie-Wiess-like along the c axis. The temperature dependence of the Hall coefficient above 108 K is accounted for by a theoretical model invoking skew scattering of conduction electrons by localized magnetic moments.
The electrical resistivity, Hall effect, and magnetic susceptibility of single-crystal UPd[sub 2]Si[sub 2] have been studied between 4.2 and 300 K. A large anisotropy was observed in both the magnetic and transport properties. There is a quadratic temperature dependence of the resistivity for a range of temperatures between 4.2 and 80 K. At higher temperatures, the resistivity indicates a Kondo-type behavior. The behavior of these quantities is accounted for by the magnetic phase transitions at 108 and 136 K reported from neutron-scattering studies. At high temperatures, the magnetic susceptibility of UPd[sub 2]Si[sub 2] is Curie-Wiess-like along the [ital c] axis. The temperature dependence of the Hall coefficient above 108 K is accounted for by a theoretical model invoking skew scattering of conduction electrons by localized magnetic moments.
The Recycler ring magnet will be made of Strontium ferrite permanent magnets. A strontium ferrite permanent magnet without compensation has a temperature coefficient of -0.2 % in dB/dT. To compensate this effect, we are utilizing 30 % Ni 70 % Fe alloy, a temperature compensation ferromagnetic material with a low Curie point. To search for optimum commercially available material and optimum condition, we made a couple of simple model magnets, and tested with several different compensating material. The test results are reported and its optimal conditions are shown. Several different configurations were tested including a possible 2 kG magnet configuration.
We report on the magnetic hyperthermia properties of chemically synthesized ferromagnetic 11 and 16 nm Fe(0) nanoparticles of cubic shape displaying the saturation magnetization of bulk iron. The specific absorption rate measured on 16 nm nanocubes is 1690+-160 W/g at 300 kHz and 66 mT. This corresponds to specific losses-per-cycle of 5.6 mJ/g, largely exceeding the ones reported in other systems. A way to quantify the degree of optimization of any system with respect to hyperthermia applications is proposed. Applied here, this method shows that our nanoparticles are not fully optimized, probably due to the strong influence of magnetic interactions on their magnetic response. Once protected from oxidation and further optimized, such nano-objects could constitute efficient magnetic cores for biomedical applications requiring very large heating power.
The magnetic properties of polycrystalline and single crystalline rare earth transition metal silicides Gd_xLa_1_-_xMSi (M =Fe, Co) were investigated. Magnetic measurements have been made in static magnetic fields up to 13 kOe and in pulsed magnetic fields up to 250 kOe in the temperature range from 4.2 to 350 K. The magnetic susceptibility in the paramagnetic state of all the investigated compounds obeys the Curie-Weiss law except for LaFeSi and LaCoSi. Increase of the La content in Gd_xLa_1_-_xFeSi compounds leads to a decrease of the Curie and Neel temperatures, which can be explained by a decrease of positive exchange interactions. (orig.).
Sensitive and quick-response nonlinear inductance characteristics are found for high Tc superconducting (YBa/sub 2/Cu/sub 3/O/sub 7-chi/) disk cores at 77K in which soft magnetic BH hysteresis loops are observed. Various quick response magnetic devices such as modulators, amplifiers and sensors are built using these cores. The magnetizing frequency can be set to more than 20 MHz, which is difficult for conventional ferromagnetic bulk materials such as Permalloy amorphous alloys and ferrite. New quick-response fluxgate type magnetic-field sensors are made using ac and dc voltage sources. The former is used for second-harmonic type sensors, while the latter is for voltage-output multivibrator type sensors. Stable and quick-response sensor characteristics were obtained for two-core type multivibrators.
The Advanced Photon Source injector synchrotron is a 7-GeV positron machine with a standard alternating gradient lattice. The calculated effect of dipole magnet strength errors on the orbit distortion, simulated by Monte Carlo, was reduced by sorting pairs of magnets having the closest simulated measured strengths to reduce the driving the term of the integer resonance nearest the operating point. This method resulted in a factor of four average reduction in the rms orbit distortion when all 68 magnets were sorted at once. The simulated effect of magnet measurement experimental resolution was found to limit the actual improvement. The {Beta}-beat factors were similarly reduced by sorting the quadrupole magnets according to their gradients.
We investigated the magnet field dependence of the X-ray pulse height and the critical current of a Ti/Au bilayer TES micro-calorimeter. The pulse height was strongly affected by the magnetic field intensity applied perpendicularly to the TES surface. We found that the critical current at zero temperature, I c0, decreased by a factor of two by applying a magnet field of ?10??T. Our data are consistent with a TES sensitivity proportional to (I/I c0)?2/3, as predicted by the Ginzburg-Landau theory. This fact implies that the shape of the R?T curve of the TES is partly determined by the critical current of the superconductor. In order to make our TES microcalorimeters less sensitive to the external magnetic field, we fabricated devices equipped with on-chip magnetic shielding. One device has ...
The Large Hadron Collider (LHC) will be equipped with several thousands of superconducting corrector magnets. Among the largest ones are the superconducting trim quadrupoles (MQTL). These twin-aperture magnets with a total mass of up to 1700 kg have a nominal gradient of 129 T/m at 1.9 K and a magnetic length of 1.3 m. Sixty MQTL are required for the LHC, 36 operating at 1.9 K in and 24 operating at 4.5 K. The paper describes the design features, and reports the measured quench performance and magnetic field quality of the production magnets. The MQTL magnet production is shared between CERN and industry. This sharing is simplified due to the modular construction, common to all twin-aperture correctors.
SummaryIn vivo tumor cell migration through integrin-dependent pathways is key to the metastatic behavior of malignant cells. Using quantitative in vivo...Full Text Available
For proper tissue morphogenesis, cell divisions and cell fate decisions must be tightly and coordinately regulated. One elegant way to accomplish this is to couple them with asymmetric cell divisions....Full Text Available
Interleukin 2 (IL-2) and B-cell growth factors I and II (BCGF I and BCGF II) are lymphokines produced by T cells that play a major role in T- and B-cell cooperation. Peripheral blood lymphocytes from...Full Text Available
Normal cells, both in vivo and in vitro, become quiescent after serial cell proliferation. During this process, cells can develop immortality with genomic instability,...Full Text Available
Somatic cell nuclear transfer or therapeutic cloning has provided great hope for stem cell-based therapies. However therapeutic cloning has been experiencing both ethical and technical difficulties....Full Text Available
Background:Stem cells can differentiate into multiple cell types, and therefore can be used for cellular therapies, including tissue repair. However, the participation of stem cells...Full Text Available
It has been postulated that thrombin binds to endothelial cells through, at least in part, cell surface glycosaminoglycans such as heparan sulfate, which could serve as antithrombin cofactor on the...Full Text Available
Hematopoietic stem cells replenish all the cells of the blood throughout the lifetime of an animal. Although thousands of stem cells reside in the bone marrow, only a few contribute to blood production...Full Text Available
In the growing chloronema cell suspension cultures of the moss Funaria hygrometrica Hedw., activities of several enzymes have been found to be cell-density-dependent. Cyclic nucleotide...Full Text Available