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Background/objectives:: The limited success in addressing the current obesity epidemic reflects the insufficient understanding of the regulation of energy balance. The present study examines the longitudinal association of body weight with physical activity (PA), total daily energy expenditure (TDEE) and total daily energy intake (TDEI). Subjects/methods:: A total of 195 adults (52% male) between 21 and 35 years of age with no intention for weight loss were followed over a 2-year period. Body weight, fat mass and fat-free mass were measured every 3 months. Participants were stratified into three groups based on change in body weight using a 5% cutpoint. TDEE and time spent in different PA intensities were determined via a multisensor device at each measurement time. TDEI was calculated based on change in body composition and TDEE. Results:: At 2-year follow-up, 57% of the participants maintained weight, 14% lost weight and 29% gained weight. Average weight change was −6.9±3.4 and 7.1±3.6 kg in the weight-loss and weight-gain groups, respectively. Average TDEE and TDEI did not change significantly in any weight change group (P>0.16). Moderate-to-vigorous PA, however, increased significantly in the weight-loss group (35±49 min/day; P<0.01) and decreased in the weight-gain group (−35±46 min/day; P<0.01). Conclusions:: Results of this observational study indicate an inverse association between body weight and PA to maintain a stable TDEE and allow for a stable TDEI over time. Sufficient PA levels, therefore, are an important contributor to weight loss maintenance.

Root hairs and arbuscular mycorrhizal fungi (AMF) increase the absorptive surface area of a root and the volume of soil explored and as such are important for nutrient acquisition in infertile soil. Root hair morphology and colonisation by AMF were compared for 10 temperate pasture species, and responses to N and P deficiency characterised. Vulpiaspp., Holcus lanatus, and Lolium rigidumhad the longest root hairs (range 1.02–2.36mm) while Trifolium subterraneumhad the shortest (~0.27mm). In contrast, T. subterraneumhad a much higher density of root hairs than any of the other species. In response to P deficiency, the length and density of root hairs generally increased; in response to N deficiency, both increases and decreases in the length and density of root hairs were observed. The annual dicotyledons T. subterraneumand Arctotheca calendulahad much higher mycorrhizal colonisation on roots grown at low P availability than the grasses. Root colonisation decreased with increasing P availability in all species. A yield advantage from mycorrhizal colonisation was demonstrated only for T. subterraneumwhen P was deficient. The potential root cylinder volume of each species was calculated as an index of the ability of the species to explore soil. Although all plant species were colonised by AMF, a positive linear relationship was observed between relative P uptake rate from the soil and the rate at which potential root cylinder volumes were developed by most species. Development of potential root cylinder volume also largely explained the critical external P requirements of most species. No such relationships were observed for N. It was concluded that knowledge of root length and the length of root hairs grown in nutrient-poor conditions may be used to predict the potential of many plant species to acquire P, and also their critical external P requirement for maximum growth. However, the study also highlighted some exceptional species.

The capability to simulate lablab production across a range of environments in northern Australia provides a useful tool for exploring agronomic and management options and risk assessments for the crop. This paper reports on the development and testing of a model of lablab (annual cultivar cv. Highworth and perennial cultivar cv. Endurance) growth, designed for use in the cropping systems simulator, APSIM (Agricultural Production Systems Simulator). Parameters describing leaf area expansion, biomass accumulation, and partitioning were derived from field experiments, and other essential parameters were assumed from similar tropically adapted legumes. The model was tested against data from experiments including different locations, cultivars, sowing dates, soil types, and water availability. Observed biomass ranged from 63 to 13055kg dry matter/ha and was predicted by the model in an independent test with a root mean square deviation of 770kg dry matter/ha. Observed time courses of biomass production for both the annual and perennial cultivars were reproduced well, as was the partitioning of biomass into leaves and stems. The effect of variable rainfall and temperature in northern Australia was analysed using the model and historical climate data. Yield reductions were found in the more inland and southern-most parts of the region where summer rainfall and/or temperatures are lower.

The capability to simulate lablab production across a range of environments in northern Australia provides a useful tool for exploring agronomic and management options and risk assessments for the crop. This paper reports on the development and testing of a model of lablab (annual cultivar cv. Highworth and perennial cultivar cv. Endurance) growth, designed for use in the cropping systems simulator, APSIM (Agricultural Production Systems Simulator). Parameters describing leaf area expansion, biomass accumulation, and partitioning were derived from field experiments, and other essential parameters were assumed from similar tropically adapted legumes. The model was tested against data from experiments including different locations, cultivars, sowing dates, soil types, and water availability. Observed biomass ranged from 63 to 13055kg dry matter/ha and was predicted by the model in an independent test with a root mean square deviation of 770kg dry matter/ha. Observed time courses of biomass production for both the annual and perennial cultivars were reproduced well, as was the partitioning of biomass into leaves and stems. The effect of variable rainfall and temperature in northern Australia was analysed using the model and historical climate data. Yield reductions were found in the more inland and southern-most parts of the region where summer rainfall and/or temperatures are lower.

Grassland production in southern Australia is generally based on phosphorus (P)- and nitrogen (N)-deficient soils. Use of P-fertiliser is necessary for high production in higher rainfall zones and economic pressures are increasing the need to apply fertiliser more widely and consistently. The P and N requirements of 10 temperate pasture species were examined to understand how increased fertiliser use will affect grassland botanical composition. The plant species fell into 2 main groups with respect to their critical external P requirements (P application rates required to achieve 90% of maximum yield):those with a high requirement (Trifolium subterraneum, Hordeum leporinum, Bromus molliformis, Microlaena stipoides, and Phalaris aquatica), and those with a low requirement (Lolium rigidum, Vulpia spp., Austrodanthonia richardsonii, and Holcus lanatus). The critical external N requirements of H. leporinum, L. rigidum, and B. molliformis were significantly higher than those of A. richardsonii, Arctotheca calendula, and H. lanatus. Species that ?tolerate' nutrient stress were relatively abundant in unfertilised grazing systems and tall ?competitor' species were dominant in fertilised pasture under low grazing pressure. The abundance of the species present in fertilised pastures grazed for high utilisation was negatively correlated with their relative growth rates and it is hypothesised that this may indicate that abundance was determined by tolerance or avoidance of grazing.

Botanical composition (basal cover) was measured in 4 replicated pasture treatments based on Phalaris aquatica and Trifolium subterraneum at Hall, ACT (unfertilised with low and high stocking rate; fertilised with low and high stocking rate) and in 2 unreplicated pasture treatments based on native perennial grasses (Austrodanthonia spp. and Microlaena stipoides) and T. subterraneum at Bookham, NSW (unfertilised and low stocking rate; fertilised and high stocking rate). Current economic pressures are encouraging graziers to increase their use of phosphorus (P) fertiliser and to adopt higher stocking rates. The objective of the research was to determine the changes in botanical composition that may result from these changes in grazing systems management.  At Hall, annual species differed in their responses to P fertility. Notably, basal cover of Bromus spp. increased significantly with P application, whereas Vulpia spp. decreased significantly. Basal cover of T. subterraneum also increased significantly with P application when stocking rate was high, but was reduced by P application if stocking rate was low. Basal cover of perennial grasses (P. aquatica and Holcus lanatus) was significantly higher at low stocking rate when P was applied. The botanical composition of high stocking rate treatments was relatively stable over time, which contrasted with less stable composition at low stocking rate.  At Bookham, fertilised pasture in unreplicated paddocks appeared to have a higher basal cover of productive annual species (i.e. Bromus spp. and T. subterraneum), but native perennial grasses appeared to have lower basal cover in comparison with the unfertilised area. These results indicated that in some cases, the influence of P fertiliser and high stocking rates on botanical composition was favourable (i.e. increased basal cover of P. aquatica and T. subterraneum) and in others it could be detrimental (i.e. lower basal cover of native perennial grasses).

The relative in vitro and in vivo toxicity of several types of manufactured fibrous glass insulation and crocidolite asbestos was investigated to aid in selection of a suitable glass fiber for subsequent use in inhalation exposures. The in vitro cytotoxicity to pulmonary alveolar macrophages of small glass fibers from microfiber insulation (count median diameter (CMD) ∼0.1-0.2 µm) was greater than that of the larger fibers from household insulation (CMD ∼2.4 µm). To screen for in vivo pulmonary toxicity, 2-21 mg of glass or asbestos fibers were administered in divided doses to male Syrian hamsters by intratracheal instillation. Animals were sacrificed at 1,3.5 and 11 months following initial administration of material. One type of glass microfiber [count median diameter (CMD) ∼0.1 µm] caused deaths from pulmonary edema at early times after instillation. High levels of asbestos, a second glass microfiber (CMD ∼0.2 µm) and one type of household insulation fiber (CMD 2.3 µm) all resulted in increases in total collagen and mild pulmonary fibrosis at later times after instillation, although microfiber insulation produced a greater response than household insulation. Asbestos insulation produced the greatest response. A five-day inhalation exposure to a high level of glass microfibers deposited in lung<10 percent of the lowest instilled amount which elicited indications of lung injury. This amount did not produce significant biological changes at 1 to 12 months after exposure.

Als Trägerelektrolyt diente bei diesem Verfahren ein Gemisch von NaCl und HCl. In Gegenwart von 4% Lumatom in Methanol wurden Oxidationspotentiale von -0,46 V für Pb und -0,68 V für Cd (gegen SKE) erhalten. Die Methode wurde auf verschiedene Referenzmaterialien (Laub, Nadeln, Haar) angewendet und auch mit der Differentialpuls-Anodic Stripping-Analyse verglichen. Bei der letzteren ergaben sich größere Schwierigkeiten, hauptsächlich durch störenden Sauerstoff.

The X-ray photoelectron spectra of nickel squarate dihydrate and of bis(2,4-pentanedionato)nickel(II) are interpreted in terms of the known crystal structures of these complexes. The comparative degree of pielectron delocalisation over metal and ligand for these complexes is also evaluated from the XPS data.

Thirty-three large felids belonging to six different species were exposed to catnip and catnip extract. The species-characteristic response to catnip and the sensitivity of the response to various concentrations of catnip were examined. Putative relationships between catnip sensitivity, species range, age, estrous cycle, and behavioral complexity are discussed. The behavioral response to catnip shown by the domestic cat is seen in several different large felids. Lions and jaguars were extremely sensitive to catnip compared to tigers, cougars, and bobcats, who gave little or no response. Both males and females of the same species tested alike. Reproductive-age adults were more sensitive than either aged or immature animals. It was quantitatively demonstrated that catnip responsiveness is not limited to the domestic cat, that it is not limited to the female, and that it varies dramatically between species and age of felids.

The pyrolysis of a suite of brown coal samples and bituminous coal maceral concentrates is investigated by non-isothermal thermogravimetry. The TG data for these coals reveal a two-stage pyrolysis process. The activation energy for the primary pyrolysis stage is considerably higher than that for the secondary pyrolysis stage. It is evident that a particular coal may be characterised by the weighted mean apparent pyrolysis activation energy which correlates with the corresponding specific energy of the coal.

A comprehensive DTA study is reported of ten polyhydroxy-phenols and eight naphthols and of the correspondingp-phenylazo benzoylchloride,p-nitrobenzoylchloride and 3,5-dinitrobenzoylchloride derivatives, prepared ’in situ’ by heating intimate mixtures of phenol and acid chloride in a conventional DTA system. The thermal analysis data and, in particular, the derivative formation temperatures, are interpreted in terms of the inductive, mesomeric and steric effects associated with the phenol and acid chloride and the extent of inter- and intramolecular hydrogen-bonding existing in these systems. The DTA data collectively, provide a comprehensive data base for the identification and characterisation of these phenols via DTA.

A comprehensive DTA study is reported of eight nitro-phenols and eight amino-phenols and of the correspondingp-phenylazobenzoylchloride,p-nitrobenzoylchloride and 3,5-dinitrobenzoylchloride derivatives, prepared ’in situ’ by heating intimate mixtures of phenol and acid chloride in a DTA system. The thermal analysis data and, in particular, the derivative formation temperatures, are interpreted in terms of the electronic and steric effects associated with the ring substituents of the phenol and acid chloride and the extent of inter- and intramolecular hydrogen bonding existing in these systems. These DTA data collectively, provide a comprehensive data base for the identification and characterisation of these phenols by DTA.

A comprehensive DTA study is reported of eight methyl-phenols, 4-methoxy-phenol and four methyl-halo-phenols and of the correspondingp-nitrobenzoylchloride, 3,5-dinitrobenzoylchloride andp-phenylazobenzoylchloride derivatives, prepared ’in situ’ by heating intimate mixtures of phenol and acid chloride in a DTA system. The thermal analysis data, in particular, the derivative formation temperatures, are interpreted in terms of the inductive, mesomeric and steric effects associated with the ring substituents of the phenol and acid chloride and the extent of inter- and intramolecular hydrogen-bonding existing in these systems. The DTA data collectively, provide a comprehensive data base for the identification and characterisation of these phenols via DTA.

TG/DTA and Thermal Degradation Mass spectrometry (TDMS) data are presented for a series of nickel(II)thiourea chloride complexes: NiL4Cl2:L=thiourea or methyl-, dimethyl-, tetramethyl-, di-n-butyl, naphthyl-, ethylene- or allylthiourea. Two different thermal decomposition mechanisms are proposed for these complexes, and it is apparent that the thermal decomposition mechanism adopted by a particular complex depends on the structure of the relevant thiourea ligand and not on the nature of the halide ligand or on the existence of geometrical isomerism for these complexes.

A new tin dithiocarbamate containing sulphur bridges, di-μ-sulphidobis [bis(N,N-diethyldithiocarbamato)tin(IV)], has been isolated from the thermal decomposition of tetrakis(N,N-diethyldithiocarbamato)tin(IV). A dimeric structure is proposed on the basis of results from mass spectrometry, infrared spectroscopy, thermal analysis and vapour pressure osmometry.

A thermogravimetry study of a series of cyclophane bis(sulfoxides) (1–6) has shown that thermal decomposition of these compounds occurs in two stages with a stepwise loss of the sulfoxide groups at well defined decomposition temperatures. The stepwise thermal cleavage has been rationalized in terms of the stereochemistry of the sulfoxide groups and the strain associated with the resultant elimination products.

The thermal decomposition of mercury(I) and (II) sulfates has been investigated by thermogravimetry. The solid-state decomposition products have been characterized by infrared and Raman spectroscopy, mass spectrometry and an X-ray diffraction method. It is concluded that mercury(I) sulfate decomposes in two steps, initially forming a mixture of metallic mercury and mercury(II) sulfate — the latter subsequently decomposes without forming a stable intermediate. The stoichiometry of disproportionation of mercury(I) sulfate and the thermal stability range of mercury(I) and mercury(II) sulfates have been established.

The purpose of these studies was to follow the development of acquired resistance in experimental cutaneous leishmaniasis by measuring changes, against time, in the ability of mice infected with Leishmania tropica to inhibit the growth of a challenge inoculum of parasites. In addition, the development of T lymphocytes that mediate the acquired response was followed by adoptive immunization. It was found that acquired resistance developed rapidly and reached a maximum level at the time when the progressive multiplication of the parasites in the primary lesion stopped. Systemic immunity, however, as determined by the ability of splenic T cells to adoptively immunize normal recipients, did not develop fully until 4 weeks later. Acquired resistance is expressed systemically in the animal and probably nonspecifically, in that mice expressing resistance to a homologous challenge with L. tropica were also capable of destroying Listeria monocytogenes. These data, obtained from in vivo studies, are consistent with the hypothesis that the immunity which causes the destruction of L. tropica is mediated by T lymphocytes and expressed, nonspecifically, through macrophages.

The combustion of brown coal chars, obtained at different pyrolysis temperatures, have been investigated using TG, DTG and DTA thermal analysis methods. The burning profiles and the kinetic parameters derived from TG and DTA data show that all the chars are less reactive than the parent coal. The higher temperature chars have lower overall reactivity. From the corresponding infrared spectra, the chars obtained at 800 °C and 1000 °C appear to have graphitic structures.

The TG and DTA profiles of compounds such as calcium oxalate monohydrate and copper sulfate pentahydrate are well known. A TMA study of these and other compounds is presented which, in addition to providing interesting data on the physical nature of phase changes and decomposition temperature ranges, confirms the classification of TMA as a principal thermal analysis technique.

A comprehensive DTA study is reported of 17 halophenols and of the corresponding p-nitrobenzoylchloride 3,5-dinitrobenzoylchloride and p-phenylazobenzoylchloride derivatives, prepared “in-situ”by heating intimate mixtures of phenol and acid chloride in the DTA system. The thermal analysis data, in particular, the derivative formation temperatures, are interpreted in terms of the inductive, mesomeric and steric effects associated with the ring substituents of the phenol and acid chloride and the extent of inter- and intramolecular hydrogen-bonding existing in these systems. The DTA data collectively provide a reference base for the identification and characterization of halophenols via thermal analysis.

Simultaneous TG, DTA techniques have been applied to investigate the combustion characteristics of Victorian brown coal derived from different coal fields and including various lithotypes. TG and DTA profiles of the entire combustion process were obtained to provide a set of parameters which characterize the oxidation potential of these coal samples. These parameters can also be used to predict the combustion performance of pulverized coal in industrial furnaces. The area of the major DTA combustion peak is closely related to the heat released during the combustion process and therefore provides a means of determining the specific energy of the coal. Different lithotypes are also characterized by their corresponding TG and DTA burning profiles.

It is evident that thermal analysis studies of Australian coals are of primary significance in the rationalisation of the various physical and chemical processes inherent in energy generation from these fossil fuels. To data, considerable such data has been accumulated correlating combustion efficiency with the coal primary structure, surface phenomena, included metal ions, volatile matter release profiles, particle size and corresponding char properties. The kinetics of these complex processes are now also modelled.

The pyrolysis in a nitrogen atmosphere of three run-of-mine samples and a suite of lithotype samples of Victorian brown coal has been investigated using simultaneous TG/DTG/DTA. The TG, DTG curves provide parameters which represent the pyrolysis properties of coal. The pyrolysis profiles can also be used as “fingerprints” of brown coal lithotypes and hence are of value in the context of the broad characterization of coal.

Lithium, sodium, potassium and ammonium bisulphate have been shown by detailed TG/DTA studies to have limited application as molten solvents. By contrast, the eutectic bisulphate systems, ammonium-potassium bisulphate and sodium-potassium bisulphate, appear to be excellent molten solvents in view of their low melting points, long liquid ranges and prolonged thermal stability at 200°. In contrast to previous studies, potassium pyrosulphate has been found to be an excellent molten solvent, provided rigorous preliminary drying procedures have been applied.

The large scale manufacture of sodium chromate is carried out by heating finely ground chromite ore mixed with sodium carbonate and lime in air. The essential reaction leading to the formation of sodium chromate is $$2Cr_2 O_3 + 4 Na_2 CO_3 + 3 O_2 \xrightarrow{{\Delta {\rm H}_{R^0 } }}4Na_2 CrO_4 + CO_2 $$

T cell-independent host resistance expressed against a primary lung infection with Cryptococcus neoformans was investigated. Following intratracheal inoculation of the yeast, BALB/cBy scid/scid mice or CD4+ plus CD8+ T cell-depleted BALB/cBy mice developed a primary lung infection that remained stable for several weeks before progressing and disseminating to kill the host. By contrast, normal BALB/cBy hosts resolved the infection after 4 to 8 weeks. Thy+ CD4- CD8- cells were found to accumulate in the pulmonary alveoli of infected scid/scid or normal mice. Depletion of these cells caused the infection to progress more rapidly and resulted 4 weeks later in a 30- to 70-fold increase in yeast numbers in the lungs and dissemination to extrapulmonary sites. Cytofluorometric studies revealed that the Thy+ CD4- CD8- cells responsible were negative for the CD3 T cell marker. A small percentage of these Thy+ CD3- cells expressed asialo-Gm1, but treatment with asialo-Gm1 antibody did not have the same infection-enhancing effect as Thy-1 monoclonal antibody treatment. Further experiments revealed that Thy-1 monoclonal antibody treatment had no effect on the establishment of infectious foci in the brain or liver following intravenous inoculation of the yeast. The data point to the existence of an early resistance mechanism for which Thy+ CD3- CD4- CD8- cells are essential. This mechanism of host defense, while insufficient for complete protection, may be capable of delaying the development of cryptococcal meningoencephalitis by restricting the growth of the yeast at primary sites of infection in the lungs, even in immunodeficient mice.

Previously published studies of experimental cutaneous leishmaniasis in the mouse have relied almost exclusively on measuring changes in lesion size to follow the course of the infection. The purposes of the studies reported here were to develop a technique to quantitate the number of viable organisms in the tissues and to use the technique to follow the development and resolution of the primary infection as well as the development of acquired resistance to Leishmania tropica in a resistant (C3H/He) and a susceptible (BALB/c) mouse strain. It was found that individual L. tropica amastigotes derived from infected tissues would transform to promastigotes and repeatedly divide to form discrete, countable colonies on rabbit blood agar. The plating efficiency was approximately 88%. Using the blood agar plating technique to quantitate the organism against time of the infection, we obtained data that suggest that acquired resistance develops in C3H/He mice earlier than is suggested by reduction in lesion size. In addition, although this resistance eliminates the parasites from the primary lesion in 10 weeks, 1,000 to 10,000 parasites persist for months in the lymph node draining the lesion site. In these studies, we found no evidence of acquired resistance in the susceptible BALB/c mice. The organism grows progressively, and the infection can disseminate to the spleen within 2 weeks. These studies illustrate the advantages of quantitating viable parasites in studies of immunity in cutaneous leishmaniasis.

The electrochemical behaviour of the adducts Cr(TPP)·Cl·L, whereTPP= tetraphenylporphyrin;L= pyridine, 2-picoline, 2,6-lutidine, 4-cyanopyridine, morpholine or 4-picoline is reported and the relationship between reduction potentials, the electron band I transition and the binding energy of the Cr2p3/2level examined.

A clear understanding of the etiology of the various forms of leishmaniasis will require knowledge of how physiological properties of the parasite and host immunity influence the pattern of development of the disease. Of particular importance are how these factors affect the growth rate of Leishmania spp. at the site of inoculation in the skin, their capacity to disseminate to visceral and distant cutaneous sites, and their capacity to multiply once there. This paper details the pattern of development of disseminated Leishmania major infection in susceptible BALB/c nu/+ and BALB/c nu/nu mice. It was found that the parasite disseminates from the hind footpad to distant cutaneous sites soon after metastatic foci are established in the liver and spleen. Both mononuclear phagocytes and neutrophils may be the vehicles for the transport of the parasite in the blood. Once visceral and cutaneous metastases are established, the parasites in those foci increase in number progressively. L. major has the capacity to multiply at visceral and cutaneous sites at the same rate. Despite the presence of viable parasites in a number of skin sites, cutaneous metastatic lesions developed almost exclusively on the feet and the tail. Furthermore, these lesions appeared to develop preferentially at sites near joints, suggesting that factors other than temperature may influence the development of cutaneous metastatic lesions.

The possible mechanisms by which CD4+ T cells prevent the dissemination of Cryptococcus neoformans from the primary site of infection in the respiratory tract were examined. It was found that even before fungicidal mechanisms are fully induced in the lungs, the host generates a CD4+ T cell-dependent inflammatory response that sequesters yeast within the pulmonary alveoli. This confinement is evident histopathologically and demonstrable objectively as a rapid decline in the ability to dislodge yeast from the lungs by bronchopulmonary lavage. One striking component of this response is the enclosure of cryptococci within multinucleated giant cells in granulomas. Studies in severe combined immunodeficient mice that were engrafted with selected lymphocyte subpopulations show that B cells, and hence anti-Cryptococcus antibodies, are not necessary for the CD4+ T cell-dependent responses that isolate and subsequently destroy this opportunistic pathogen in the lung parenchyma.

This study examined the capacity of BALB/c mice that had been depleted of T cell subpopulations to generate a protective immune response to Leishmania major. Thymectomized mice were depleted of either L3T4+ (CD4+) T lymphocytes, Ly2+ (CD8+) T lymphocytes, or both, by treatment with appropriate mAbs. It was found that susceptible mice were rendered resistant to Leishmania by an intravenous infusion of anti-L3T4 mAb. These mice generated an immune response that destroyed the parasite in the primary lesion and in visceral metastatic foci. CD4+ cell-depleted mice also acquired a capacity to mount a sustained delayed-type hypersensitivity (DTH) response to parasite antigens, indicating that DTH, per se, is not a disease-promoting mechanism in the susceptible murine host as has been suggested. Depleting BALB/c mice of CD8+, as well as CD4+ T cells, left them highly susceptible to Leishmania infection, thereby indicating that CD8+ lymphocytes are key protective cells. Our results can be interpreted as showing that the susceptibility of BALB/c mice is due to the generation of CD4+ cells that suppress either the generation or expression of CD8+ T cell-mediated antiLeishmania immunity.

Infrared, electronic, electron spin resonance and d.c. polarographic data for some copper(II) tetraaza macrocyclic complexes, involving a novel cyclam type ligand, are reported and are interpreted in terms of the structure of the complexes and the influence ofJahn-Teller distortion effects and cation-anion interactions.

Qualitative infrared and electronic spectroscopic data for a series of nickel(II) amine complexes suggest structures involving octahedral (transtetragonal) symmetry and associated with varying degrees of cation-anion interaction. N-methyl ligand substituents contribute significantly to ligand conformations, complex symmetry, and cation-anion steric interactions. From the electronic data, the parametersDq,B',C,C/B', ß35, andZ* are determined for each complex and a spectrochemical and nephelauxetic series is proposed for the associated amine ligands.

The chemistry of the metal dithiocarbamates and related complexes has been extensively reviewed previously. The book, The Dithiocarbamates and Related Compounds by Thorn and Ludwig1 is generally recognized as the classic reference text for metal dithiocarbamate chemistry. Very broad and detailed reviews on transition metal (including lanthanides and actinides) and nontransition metal dithiocarbamates and xanthates have been published by Coucouvanis,2,3 which concisely discuss synthesis, spectroscopic data, magnetic moments, x-ray structural data and adduct synthesis and characterization. The analytical chemistry of metal dithiocarbamates and related compounds has been extensively reviewed by Magee4 and very recently by Magee and Hill.5 These reviews discuss in detail the electroanalytical, separatory, radiochemical, thermoanalytical, spectroscopic, mass spectrometric, titrimetric and ion. selective electrode aspects of these complexes. The electrochemistry and redox behavior of transition metal dithiocarbamates have been comprehensively reviewed by Bond and Martin6 and the thermochemistry of metal dithiocarbamates, metal xanthates and metal dithiophosphates has been reviewed by Hill and Magee7 with emphasis on thermal decomposition mechanisms of these complexes, as derived by thermal analysis techniques in conjunction with mass spectrometry and the solution thermochemistry leading to metal-ligand bond energies. Sengupta and Kumar8 have published a short, incomplete review of some thermal analysis data for metal dithiocarbamate complexes.

The contribution of T lymphocyte subpopulations to intrapulmonary and systemic resistance against an opportunistic strain of Cryptococcus neoformans was examined. It was found that C. neoformans was destroyed when introduced into the lungs of normal mice, but disseminated to the brains of mice treated with an antibody that depleted them of CD4+ T cells. Depletion of either CD8+ or CD4+ T cells impaired the ability of the host to clear the yeast from the lung. These results, together with the observation that CD8+ T cells accumulate in the lungs of CD4+ T cell-deficient mice, suggest that CD8+ T cells play an important role in resistance to C. neoformans infection acquired via the respiratory tract.

The research in thermal analysis and calorimetry, conducted by the author over the period 1964 to 1993, is summarised and concisely reviewed. The major investigations have focussed on thermal analysis studies of coordination compounds, particularly the metal dithiocarbamate complexes. A significant solution calorimetric study of some metal dithiocarbamate complexes has also been undertaken. DSC has been applied to determine the sublimation enthalpies of many metal dithiocarbamate and metal pentane-2,4-dionate complexes and solution calorimetry has been applied to study the thermochemistry of the latter group of complexes. Thermal analysis investigations of several inorganic molten salt systems have been initiated. Thermometric titrimetry has been applied to study metal-macrocyclic ligand systems in aqueous media and particularly those systems of environmental significance. Temperature calibration standards for TMA have been proposed and TMA has been applied to study the mechanical properties of several common inorganic compounds. DTA has been applied to study a wide variety of phenols and has subsequently been applied as an analytical technique to determine the components of solid state phenol mixtures. Thermometric titrimetry has been applied to determine the phenolic content of wines. A comprehensive thermal analysis study of Australian brown coal has been undertaken, involving the DSC determination of coal specific energy, a TG/DTA study of the coal pyrolysis and combustion processes and a TG/DTA and EGA study of the cation catalytic effect on the coal pyrolysis process. Thermal analysis and calorimetric techniques have been extensively publicised and promoted by the publication of specialist reviews, the presentation of symposia review papers and the oral presentation of short courses, particularly in the SE Asian region. This review essentially reveals the diversity of possible application of thermal analysis and calorimetric techniques and the primary significance of thermodynamic data in the fundamental rationalisation of chemical phenomena.

A short review of the thermal analysis data available for dithiocarbamate complexes of tin(II) and tin(IV) is presented. Since the relevant thermal decomposition mechanisms are complicated, even for decompositions in inert atmospheres, mechanisms postulated on the basis of thermal analysis data alone are suspect. Realistic thermal decomposition mechanisms for these complexes can only be formulated when the relevant decomposition products are unambiguously identified. In this short review, an attempt is made to identify trends in these thermal analysis data, with particular reference to structural features of the corresponding complexes.

The thermal decomposition products of copper dimethyldithiocarbamate and copper diethyldithiocarbamate have been semi-quantitatively analyzed by a combined gas chromatography — mass spectrometry technique and thermal decomposition mechanisms for both complexes are proposed. The fragmentation pathway is strongly influenced by the nature of the terminal alkyl group attached to the dithiocarbamate moiety.

Samples were obtained from selected positions in the process stream of an experimental low Btu gasifier using a five-stage multicyclone train and a four-stage condenser train. These materials which represent potential fugitive emissions were screened for mutagenic activity (AmesSalmonella mammalian microsome mutagenicity assay) and forin vitro cytotoxicity (alveolar macrophages). Size-fractionated materials collected in the multicyclone train were mutagenic inSalmonella tester strains TA-98 and TA-100 and were also cytotoxic. There appeared to be no relationship between aerosol droplet size and mutagenic activity. Studies with condenser train samples indicate that neutral and basic polynuclear aromatic compounds contribute to the mutagenicity of process stream materials. Specific mutagenic and cytotoxic activity of material was reduced as gas underwent cleanup. A reduction in the mass loading of potentially toxic compounds is achieved by the control devices in the process stream of the experimental gasifier being developed and tested by METC, and assuming equal probability of emissions throughout the process stream, risk from exposure to potential fugitive emissions is reduced as the gas is cleaned.