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New Probe (new + probe)
Selected AbstractsFunnel Complexes with CoII and NiII: New Probes into the Biomimetic Coordination Ability of the Calix[6]arene-Based Tris(imidazole) SystemEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 9 2004Olivier Sénèque Abstract The coordination properties of the calix[6]arene-based tris(imidazole) ligand X6Me3Imme3 were further explored with CoII and NiII. This imidazole system stabilizes tetrahedral mononuclear CoII complexes with an exchangeable fourth exogenous ligand (water, alcohol, amide) located at the heart of the hydrophobic calixarene cavity. With a weak donor ligand such as a nitrile, both four-coordinate tetrahedral and five-coordinate trigonal bipyramidal complexes were obtained. The latter contains a second nitrile molecule trans to the included guest nitrile. These complexes were characterized in solution as well as in the solid state. The NiII complexes are square-based pyramidal five-coordinate edifices with a guest nitrile inside the cavity and a water molecule outside. A comparison with previously described ZnII and CuII complexes emphasizes the flexibility of this ligand. A comparison with carbonic anhydrase, a mononuclear zinc enzyme with a tris(histidine) coordination core, shows that X6Me3Imme3 displays many structural features of this enzyme except for the cis coordination of the exogenous ligands. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] New probe for the measurement of dynamic changes in the rectumNEUROGASTROENTEROLOGY & MOTILITY, Issue 1 2004I. S. Andersen Abstract, Conventional mano-volumetric techniques cannot measure changes in circumferential dimensions at several axial positions within a bowel segment. Our aims were to validate a new impedance planimetry probe for simultaneously measuring the cross-sectional area (CSA) at five axial positions in vitro and in vivo in 10 anesthetized pigs. The day-to-day coefficient of variation (CV) for CSA measured by the probe in cylindrical tubes of known diameter was 0.8,9.5%. The mean from actual diameter deviation ranged from 2.3 to 6.7%. In a conical tube the day-to-day CV was 2.3,8% and mean percentage deviation ,2.8 to 1.0. Interposed narrowing sections caused a total CV of 7,13%. In vivo studies revealed variations in CSA, associated with expulsion of flatus. It is concluded that impedance planimetry allows simultaneous measurement of CSA at several levels within the rectum. In vitro validity was acceptable and alterations in lumen diameter were identified in vivo. [source] Newly Developed Ultrasonic Probe With Ropeway System for Transpapillary Intraductal Ultrasonography of the Bilio,Pancreatic Ductal SystemDIGESTIVE ENDOSCOPY, Issue 3 2000Naotaka Fujita Background: Intraductal ultrasonography of the bile/pancreatic duct using a thin-caliber ultrasonic probe (IDUS) provides excellent images of these ducts and the surrounding structures. Insertion of the device through the papilla of Vater is essential to carry out this examination. We developed a new probe with a ropeway system (XUM5RG-29R; Olympus, Tokyo) for transpapillary IDUS. Its usefulness such as ease of application and safety were prospectively evaluated. Patients and methods: During the period of October 1997 to April 1998, transpapillary IDUS using the probe was performed in 194 patients at seven medical institutions. The success rates of insertion of the probe into the bile/pancreatic duct, observation of the area of interest, and the incidence of complications were evaluated. Results: Passage of the probe through the papilla was successful without difficulty in all the patients. Successful introduction of the probe into the pancreatic duct, bile duct and both of the ducts was achieved in 98.4, 100 and 85% of the patients, respectively. Once the probe was introduced into the aimed duct, it was possible to obtain IDUS images of the area of interest in all but five patients. Mild acute pancreatitis developed in eight patients (4.1%), all of whom recovered with conservative therapy only. Conclusions: It is possible to introduce the new ultrasonic probe into the desired duct once a guide wire has been inserted. This type of ultrasonic probe is quite useful when performing transpapillary IDUS of the bile and/or pancreatic duct. [source] Interaction between the fluorinated amphiphilic copolymer poly(2,2,3,4,4,4-hexafluorobutyl methacrylate)- graft -poly(SPEG) and DNAJOURNAL OF APPLIED POLYMER SCIENCE, Issue 1 2010Ling Li Abstract A synthesized copolymer, synthesized from HFMA (hexaflurobutyl methacrylate) and SPEG (PHFMA- g -PSPEG), was synthesized. PHFMA- g -PSPEG intercalated to the DNA base pair via a strong hydrophobic force, and this was conformed by ultraviolet spectroscopy, transmittance measurements, micropolarity measurements, resonance light scattering (RLS) spectroscopy, and particle size measurements. The copolymer was used as a new probe to detect DNA according to the RLS technique. The hydrophobic interaction between PHFMA- g -PSPEG and DNA significantly enhanced the RLS signal, and the enhanced RLS intensity at 422 nm was proportional to the nucleic acid concentration within the range of 0.09,0.90 mg/L with a detection limit (3,) of 4.0 ,g/L. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source] Precision cosmology with voids: definition, methods, dynamicsMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 3 2010Guilhem Lavaux ABSTRACT We propose a new definition of cosmic voids based on methods of Lagrangian orbit reconstruction as well as an algorithm to find them in actual data called DynamIcal Void Analysis. Our technique is intended to yield results which can be modelled sufficiently accurately to create a new probe of precision cosmology. We then develop an analytical model of the ellipticity of voids found by our method based on the Zel'dovich approximation. We measure in N -body simulation that this model is precise at the ,0.1 per cent level for the mean ellipticity of voids of size greater than ,4 h,1 Mpc. We estimate that at this scale we are able to predict the ellipticity with an accuracy of ,,, 0.02. Finally, we compare the distribution of void shapes in N -body simulation for two different equations of state w of the dark energy. We conclude that our method is far more accurate than Eulerian methods and is therefore promising as a precision probe of dark energy phenomenology. [source] Use of Selenium to Detect Mercury in Water and Cells: An Enhancement of the Sensitivity and Specificity of a Seleno Fluorescent ProbeCHEMISTRY - A EUROPEAN JOURNAL, Issue 13 2009Bo Tang Prof. Abstract Seleno fluorescent probe: An organoselenium fluorescent probe (FSe-1) for mercury was designed based on the irreversible deselenation mechanism. FSe-1 exhibits an ultrahigh selectivity and sensitivity for Hg2+ detection only for reactive selenium atom sites, due the strong affinity between Se and Hg. Furthermore, the new probe has been successfully used for imaging mercury ions in RAW,264.7 cells (a mouse macrophage cell line; see figure). Inspired by the antitoxic function of selenium towards heavy-metal ions, we designed an organoselenium fluorescent probe (FSe-1) for mercury. The reaction of FSe-1 and Hg2+ is an irreversible deselenation mechanism based on the selenophilic character of mercury. FSe-1 exhibits an ultrahigh selectivity and sensitivity for Hg2+ detection only for reactive selenium atom sites due to the strong affinity between Se and Hg. The experimental results proved that FSe-1 was selective for Hg2+ ions over other relevant metal ions and bioanalytes, and also showed an enhancement in sensitivity of up to 1.0,nM, which is lower than the current Environmental Protection Agency standard for drinking water. Furthermore, the new probe has been successfully applied to the imaging of mercury ions in RAW,264.7 cells (a mouse macrophage cell line) with high sensitivity and selectivity. [source] New tools for labeling silica in living diatomsNEW PHYTOLOGIST, Issue 3 2008Julien Desclés Summary ,,Silicon biomineralization is a widespread mechanism found in several kingdoms that concerns both unicellular and multicellular organisms. As a result of genomic and molecular tools, diatoms have emerged as a good model for biomineralization studies and have provided most of the current knowledge on this process. However, the number of techniques available to study its dynamics at the cellular level is still rather limited. ,,Here, new probes were developed specifically to label the pre-existing or the newly synthesized silica frustule of several diatoms species. ,,It is shown that the LysoTracker Yellow HCK-123, which can be used to visualize silica frustules with common filter sets, presents an enhanced signal-to-noise ratio and allows details of the frustules to be imaged without of the use of ionophores. It is also demonstrated that methoxysilane derivatives can be coupled to fluorescein-5-isothiocyanate (FITC) to preferentially label the silica components of living cells. ,,The coupling of labeling procedures might help to address the challenging question of the process of frustule exocytosis. [source] Quantum criticality and novel phases: Summary and outlookPHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 3 2010A. J. Schofield Abstract This conference summary and outlook provides a personal overview of the topics and themes of the August 2009 Dresden meeting on quantum criticality and novel phases. The dichotomy between the local moment and the itinerant views of magnetism is revisited and refreshed in new materials, new probes, and new theoretical ideas. New universality and apparent zero temperature phases of matter move us beyond the old ideas of quantum criticality. This is accompanied by alternative pairing interactions and as yet unidentified phases developing in the vicinity of quantum critical points. In discussing novel order, the magnetic analogs of superconductivity are considered as candidate states for the hidden order that sometimes develops in the vicinity of quantum critical points in metallic systems. These analogs can be thought of as "pairing" in the particle,hole channel and are tabulated. This analogy is used to outline a framework to study the relation between ferromagnetic fluctuations and the propensity of a metal to nematic type phases , which at weak coupling correspond to Pomeranchuk instabilities. This question can be related to the fundamental relations of Fermi liquid theory. [source] | ||||||||||||||||