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N J Coleman

Publications and source records attributed to N J Coleman.

14 recordsLinked to original sources
PubMed2006

Calcium silicate sorbent from secondary waste ash: heavy metals-removal from acidic solutions.

The layer lattice, ion-exchange material, Al-substituted 11 A tobermorite, has been synthesised via an alkaline hydrothermal route from a secondary waste ash arising from newsprint recycling. The hydrogarnet, katoite (Ca3Al2SiO12H8), was also formed. Batch sorption analyses have confirmed that the Al-substituted 11 A tobermorite-bearing product is an effective sorbent for Co2+, Cd2+ and Zn2+ ions from acidified aqueous media. Kinetic sorption data were analysed in accordance with the pseudo-first- and pseudo-second-order models and steady state data were fitted to the Langmuir and Freundlich isotherms. The Langmuir and pseudo-second-order models provided the most appropriate descriptions of the sorption processes. The maximum uptake capacities for Co2+, Cd2+ and Zn2+ at 20 degrees C were found to be 10.47, 2.92 and 3.09 mg g(-1), respectively, and the respective apparent pseudo-second-order rate constants were estimated to be 5.08 x 10(-3), 1.10 x 10(-3) and 1.13 x 10(-3) g mg(-1) min(-1).

Adsorption↗
PubMed2000

Bacteriostatic action of a novel four-component bioactive glass.

Bacterial adhesion to biomaterials causing biomaterial-centered infection and poor tissue integration is a problem that limits the extensive use of many biomaterial devices in clinical applications. Bioactive materials are those biomaterials that form a compliant, mechanically stable bond with host tissue. Sol-gel-derived glasses in the three-component system SiO(2)-CaO-P(2)O(5) exhibit bioactivity that is dependent on composition and texture (i.e., specific surface area, pore size, structure, and distribution). The in vitro bioactivity and antibacterial action of a novel sol-gel-derived glass, AgBG, in the system SiO(2)-CaO-P(2)O(5)-Ag(2)O are compared with those of its three-component counterpart, BG. The incorporation of 3-wt % Ag(2)O conferred antimicrobial properties to the glass without compromising its bioactivity. AgBG exhibited a marked bacteriostatic effect on E. coli MG1655 with a minimum inhibiting concentration of 0.2 mg (biomaterial)/mL (culture solution), above which bacterial growth was reduced to 0.01% of that of the control culture. In comparison, BG did not possess antimicrobial properties over the concentration range investigated (0.1-40.0 mg/mL).

Anti-Bacterial Agents↗
PubMed2000

Tensile properties of bioactive fibers for tissue engineering applications.

Cell transplantation using biocompatible, biodegradable scaffolds offers the possibility of creating or regenerating tissue to replace organ function when deficiency arises. The role of these temporary substrates is to support and guide the expanding cell culture until it becomes structurally integrated with the host tissue. 45S5 Bioglass(R) is a 4-component, melt-derived bioactive glass, which has been approved for human clinical use by the Food and Drug Administration. The biocompatibility and biodegradability of 45S5 Bioglass(R) are long established, whereas research into its performance as an extracellular scaffold is currently underway. In this study the tensile strengths (93 +/- 8 and 82 +/- 14 MPa), elongation to fracture (0.7 +/- 0.05%) and Weibull's moduli (3.0 and 3.5) of 45S5 Bioglass(R) fibers (mean diameters 193 and 280 microm) for tissue engineering applications are reported. The tensile strengths of the fibers are compared with those of bulk 45S5 Bioglass(R) and a range of biodegradable polymer materials currently used in the field of tissue engineering. Aspects of glass and fiber technology relevant to the design and manufacture of extracellular ceramic scaffolds are also discussed.

Animals↗
PubMed1999

Evaluating arterial blood gas results.

Previously in this Clinical Update series we examined how the body regulates acids and bases. If information about acid-base balance is to be useful, we need to know how to interpret arterial blood gases (ABGs) so we can intervene rapidly when the body is unable to restore a normal acid-base balance in the face of an overwhelming derangement.

Blood Gas Analysis↗
PubMed1998

Demystifying acid-base regulation.

Acid-base imbalances may have serious clinical implications for all patients. The maintenance of homeostasis within the body is intimately linked to the balance of acids and bases within the body. Any disturbance in this balance will adversely effect all cellular metabolism and ultimately the functioning of vital body systems. Figure 3 may help you to understand the integration of the mechanisms which regulate acid-base balance in the body.

Acid-Base Equilibrium↗
PubMed1996

What is this thing called 'Internet'?

According to a survey conducted by the Australian Journal of Nursing in 1994, 43% of nurses owned personal computers and another 28% were considering the purchase of one in the next year. Given such a high ownership rate, and the interest in the 'Net' itself, some understanding of the fundamentals of online computing and the Internet would seem timely.

Australia↗
PubMed1995

Regulation of neurotensin receptor mRNA expression by the receptor antagonist SR 48692 in the rat midbrain dopaminergic neurons.

In this study, we demonstrated that the tyrosine hydroxylase-like immuno-reactive (possibly dopaminergic) neurons express neurotensin receptor mRNA in the rat substantia nigra and in the ventral tegmental area. Additionally, 2 weeks treatment with the neurotensin receptor antagonist SR 48692 increased mRNA levels in the substantia nigra. These data suggest that neurotensin receptor expression in the perikarya and in the terminal regions of dopaminergic neurons is regulated by its endogenous agonist in vivo.

Animals↗
PubMed1995

Regulation of daily rhythm of body temperature by neurotensin receptor in rats.

It is proposed that neurotensin receptor mediated signal transduction may play an important role in the thermoregulatory control in the brain. In this study, a significant increase in body core temperature was observed with SR 48692, a neurotensin receptor antagonist, after treatment of rats at light phase when the temperature is regulated low. On the other hand, SR 48692 delayed the physiological decline of body core temperature at dark phase when the temperature is highly regulated. We also found slight daily rhythmicity, though not significant, in neurotensin/neuromedin N precursor protein mRNA levels in the medial preoptic nucleus using in situ hybridization technique. Our results support the hypothesis that endogenous neurotensin receptor agonists play a physiological role in the central modulation of body core temperature in rats.

Animals↗
PubMed1992

A preliminary investigation of the imaging performance of photostimulable phosphor computed radiography using a new design of mammographic quality control test object.

Leeds Test Object TOR[MAM] has been designed to supplement the current FAXIL mammography test object TOR[MAX]. It contains a range of details that have a more natural radiographic appearance and has been designed as a test that more closely approximates the image quality achieved in clinical mammography. Physical aspects of the design and implementation of TOR[MAM] are presented. The TOR[MAM] has been used in a preliminary physical evaluation of the comparative image qualities produced by conventional (screen-film) and photostimulable phosphor computed mammography and the results are discussed. TOR[MAX] results are also presented. The influence of digital image processing (enhancement) on the image quality of computed mammograms is also considered. The results presented indicate the sensitivity of TOR[MAM].

Female↗
PubMed1985

A set of X-ray test objects for quality control in television fluoroscopy.

The history of performance testing in Leeds of television fluoroscopic systems is briefly outlined. Using the visual, physical and technological requirements as a basis, a set of nine test objects for quality control in television fluoroscopy is described. The factors measured by the test objects are listed in the introduction; the test objects and their function are fully described in the remainder of the paper. The test objects, in conjunction with a television oscilloscope, give both subjective and objective information about the X-ray system. Three of the test objects enable the physicist or engineer to adjust certain aspects of the performance of the X-ray system. The set of nine test objects is available commercially.

Fluoroscopy↗
PubMedDate not supplied

Nursing the Net.

Explore the source record for details and available documents.

Computer Communication Networks↗