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The Janice Lake Cu-Ag mineralization in the Wollaston Domain of northern Saskatchewan is hosted by a metasedimentary sequence in the upper part of the Wollaston Supergroup of the Trans-Hudson orogen. The Wollaston Supergroup was deposited between ~ 2070 and 1865 Ma in a foreland basin setting constructed over Archean basement of the Hearne craton. The Trans-Hudson orogen underwent final collision and peak metamorphism at ~ 1810 Ma, during consolidation of Laurentia and its amalgamation with the Columbia supercontinent. Titanite is a common constituent of the post-peak metamorphic assemblages of Trans-Hudson lithotectonic units and accompanied disseminated sediment-hosted Cu sulfide mineralization at Janice Lake. Titanite crystals, intergrown with chalcocite over a strike-length of ~ 2 km of Cu-bearing stratigraphy, were dated by the ID-TIMS and LA-ICP-MS U-Pb methods, returning an age range from 1780 to 1760 Ma and a weighted average age of 1775 ± 10 Ma. The titanite ages effectively date the associated chalcocite-dominated sediment-hosted Cu-Ag mineralization and its formation during initial post-orogenic uplift and cooling, ~ 30 myr after peak metamorphism. The age-range and tectonic setting of the Janice Lake mineralization confirms that sediment-hosted Cu mineralization was an integral part of the metallogenic endowment of Columbia and that its emplacement coincided with the continental-scale Trans-Hudson orogeny rather than with diagenesis and extensional basin development ~ 100 myr earlier.

The sediment-hosted stratiform Cu ± Co deposits and prospects of the Central African Copperbelt are characterized by two intimately associated mineralization styles: disseminated sulfides and sulfide-bearing quartz-carbonate veins and veinlets. It has been widely accepted that the disseminated mineralization was introduced during sediment diagenesis in a rift setting, and possibly in multiple events spanning several hundred million years. In contrast, the veinlet-hosted mineralization is commonly thought to have been derived either by remobilization of the disseminated sulfides during the Lufilian collisional orogeny or introduced at broadly the same time(s) as the disseminated sulfides during diagenesis and subsequent orogeny. The results of 15 Re-Os molybdenite age determinations from Cu ± Co deposits and prospects across the Zambian part of the Central African Copperbelt suggest that both the disseminated and veinlet mineralization styles were indeed generated together, but in a 50-myr Cambrian window (~540–490 Ma) during the later stages of the Lufilian collisional orogeny. The molybdenite ages for the disseminated stratiform mineralization at two localities do not support the notion of syndiagenetic Cu introduction. The molybdenite ages also show that individual deposits formed over minimum time intervals of ~10–24 myr.

The Cadia district of New South Wales contains four alkalic porphyry Au-Cu deposits (Cadia East, Ridgeway, Cadia Hill, and Cadia Quarry) and two Cu-Au-Fe skarn prospects (Big Cadia and Little Cadia), with a total of ~50 Moz Au and ~9.5 Mt Cu (reserves, resources, and past production). The ore deposits are hosted by volcaniclastic rocks of the Weemalla Formation and Forest Reefs Volcanics, which were deposited in a submarine basin on the flanks of the Macquarie Arc during the Middle to Late Ordovician. Alkalic magmatism occurred during the Benambran orogeny in the Late Ordovician to early Silurian, resulting in the emplacement of monzonite intrusive complexes and the formation of porphyry Au-Cu mineralization. Ridgeway formed synchronous with the first compressive peak of deformation and is characterized by an intrusion-centered quartz-magnetite-bornite-chalcopyrite-Au vein stockwork associated with calc-potassic alteration localized around the apex of the pencil-like Ridgeway intrusive complex. The volcanic-hosted giant Cadia East deposit and the intrusion-hosted Cadia Hill and Cadia Quarry deposits formed during a period of relaxation after the first compressive peak of the Benambran orogeny and are characterized by sheeted quartz-sulfide-carbonate vein arrays associated with subtle potassic, calc-potassic, and propylitic alteration halos.

Sediment-hosted stratiform copper–silver mineralization is common in Middle Creston strata of southeastern British Columbia, a correlative lithostratigraphic unit of the Ravalli Group of western Montana. The Ravalli Group hosts the largest sediment-hosted stratiform copper–silver deposits of the Belt-Purcell Supergroup. Strata of the Belt-Purcell Supergroup accumulated between ~1540 and 1300 Ma in a pericratonic rift basin (Belt-Purcell basin) constructed over Archean and Paleoproterozoic blocks of Laurentia. The basin underwent several events of deformation and metamorphism at ~1380–1325 Ma (East Kootenay orogeny), ~1200–1000 Ma (Grenvillian), and 900–800 Ma (Goat River orogeny) prior to Meso-Cenozoic Cordilleran tectonism. U–Pb geochronology of detrital zircons from Middle Creston rocks define a maximum age of deposition of ~1470 Ma, in agreement with the established age range for the Belt-Purcell Supergroup in southeastern British Columbia. Molybdenite is locally part of the sediment-hosted stratiform copper–silver mineralization in the region, either as isolated grains within mineralized strata or in paragenetic sequence with the cupriferous sulfides. Re–Os geochronology on molybdenite reveals repetitive episodes of fluid flow through Middle Creston strata in the study area, with principal events at 1170–1140 and 1043–990 Ma. Paragenetically constrained molybdenite, in growth sequence with bornite and chalcocite, yields an age of 1043 ± 6 Ma. Hence, the fluid responsible for the sediment-hosted stratiform copper–silver mineralization in southeastern British Columbia permeated the host sequence ~440 m.yr. after its deposition, coincident with the Grenville-age metamorphic event at ~1200–1000 Ma. Such tectono-thermal activity extended along the western margin of Laurentia beyond the limits of the Belt-Purcell basin, and was a far-field response to orogen-scale collisions taking place off Laurentia during Rodinia assembly.

Effective teaching and learning in higher education is an important focal point of literature around the globe. Various models are presented as desirable and fostering optimal conditions for teaching and learning. However, each model must be examined within the context of its institutional culture, mission and strategic plan to ascertain if it meets the envisaged goals. The Reinventing Teaching Project survey conducted at Flinders University in 2009 provided a unique opportunity for academic staff and students across all faculties to respond to a survey that explored their perceptions of optimal learning conditions and assessed if the campus environment was conducive to effective teaching and learning practices. The exploratory study was designed to gather qualitative and quantitative data on the motivation of teachers and learners to engage with learning and learners (or not). The results of the survey present valuable insights into what teachers and learners consider to be important attributes of optima...

In world regions receiving direct foreign aid, beneficiaries of aid often lack the education required to remove themselves from poverty. Micro-lending refers to the initiation of small loans to the neediest of borrowers who are unable to secure traditional financing from financial intermediaries. In order for micro-lending to thrive as a viable alternative to traditional government aid, borrowers must not only receive a loan, but also an education in business to fully equip borrowers with necessary resources to establish and operate a prosperous business entity. The authors will argue for the provision of increased educational resources and discuss the disparities between the US model of education and that of third-world nations. Furthermore, the authors will prescribe steps to develop educational materials and train micro-credit borrowers to better guarantee the viability of microfinance.

BACKGROUND: Malignant mesothelioma (MM) is an aggressive cancer of serosal membranes, mostly pleura. It is related to asbestos exposure and its incidence in most industrialized countries is projected to remain stable or to increase until 2020. Prognosis remains poor. Clinical prognostic scoring systems lack precision. No prognostic tissue markers are available. Aquaporin 1 (AQP1) is a cell membrane channel involved in water transport, cell motility, and proliferation. A blocker and an agonist are available. METHODS: Two independent cohorts of MM were studied. Cohort 1 consisted of 80 consecutive patients who underwent radical surgery (extrapleural pneumonectomy [EPP]). Cohort 2 included 56 conservatively managed patients from another institution. Clinical information was obtained from files. Diagnoses were histologically verified. Immunohistochemical labeling for AQP1 was performed on tumor tissue and the percentage of positive cells was scored. RESULTS: We demonstrated expression of AQP1 in normal and neoplastic mesothelium at the apical aspect of the cell, in keeping with a role in water transport. For both cohorts, expression of AQP1 by ≥50% of tumor cells was associated with significantly enhanced survival (9.4 months vs 30.4 months in EPP patients and 5 months vs 15 months in conservatively treated patients). This was independent of established prognostic factors, including histologic subtype, pathologic stage, sex, and age at time of diagnosis. CONCLUSION: Expression of AQP1 correlated significantly with prognosis in MM, irrespective of treatment or established prognostic factors. Immunohistochemical labeling for AQP1 should be included in the routine histopathologic workup. An agonist or blocker may become useful for treatment.

Although the water channel protein aquaporin-1 (AQP1) is widely observed outside the rat brain in continuous, but not fenestrated, vascular endothelia, it has not previously been observed in any endothelia within the normal rat brain and only to a limited extent in the human brain. In this immunohistochemical study of rat brain, AQP1 has also been found in microvessel endothelia, probably of the fenestrated type, in all circumventricular organs (except the subcommissural organ and the vascular organ of the lamina terminalis): in the median eminence, pineal, subfornical organ, area postrema and choroid plexus. The majority of microvessels in the median eminence, pineal and choroid plexus, known to be exclusively fenestrated, are shown to be AQP1-immunoreactive. In the subfornical organ and area postrema in which many, but not all, microvessels are fenestrated, not all microvessels are AQP1-immunoreactive. In the AQP1-immunoreactive microvessels, the AQP1 probably facilitates water movement between blood and interstitium as one component of the normal fluxes that occur in these specialised sensory and secretory areas. AQP1-immunoreactive endothelia have also been seen in a small population of blood vessels in the cerebral parenchyma outside the circumventricular organs, similar to other observations in human brain. The proposed development of AQP1 modulators to treat various brain pathologies in which AQP1 plays a deleterious role will necessitate further work to determine the effect of such modulators on the normal function of the circumventricular organs.

PurposeThe purpose of this paper is to audit the use of three strategies for protecting hospital inpatients with allergies: red allergy wristbands for patients with allergies; white identification wristbands for all patients; and completion of an “allergy box” on drug charts. The paper also aims to assess the impact of making pharmacists responsible for ensuring allergy box completion.Design/methodology/approachThe setting was The Whittington Hospital, London, a district general hospital. Two cross‐sectional studies were conducted 11 months apart, before and after pharmacists were made responsible for ensuring allergy box completion. The studies involved 186 (pre‐intervention) and 250 (post‐intervention) unselected adult patients.FindingsThe proportion of blank allergy boxes decreased significantly from 24.7 per cent to 5.2 per cent (pp=0.206). Similarly, the second study showed a non‐significant decrease in the proportion of patients lacking identification wristbands from 12.9 per cent to 10.8 per cent (p=0.499).Practical implicationsA formal checking system is required for allergy and identification wristbands to improve use of these basic, inexpensive measures for preventing drug errors.Originality/valueThe paper shows that making pharmacists responsible for ensuring allergy status documentation on drug charts significantly increased use of this safety measure.

Twenty-one alkalic porphyry deposits of Late Ordovician to Early Silurian age occur in two mineral districts in New South Wales. The Cadia and Northparkes districts formed in shoshonitic volcanic centres where a major basement structure (the Lachlan Transverse Zone) cut the Ordovician Macquarie Arc obliquely. Processes of mineralisation in both districts were centred in and around quartz monzonite porphyry complexes that intruded the volcanic centres. These composite intrusive complexes comprise pipes, dykes and stocks. Hydrothermal alteration in and around the intrusions produced a complex sequence of potassic, calc-potassic, sodic, propylitic and late stage, typically fault- and fracture-controlled phyllic assemblages. Hematite dusting was a common alteration product giving the intrusions and the altered volcano-sedimentary host sequences a distinctive pink-orange coloration. Several of the deposits have bornite-rich cores, chalcopyrite-dominant annuli and pyritic outer haloes. Gold is well correlated w...

The Cadia district, located in the eastern Lachlan fold belt of New South Wales, Australia, comprises four gold-copper porphyry deposits (Ridgeway, Cadia Quarry, Cadia Hill, and Cadia East) and two related ironcopper- gold skarn deposits (Big Cadia and Little Cadia). These deposits formed along a northwest-striking, arctransverse structural corridor within the intraoceanic Macquarie arc. This arc is composed of a belt of Early Ordovician to Early Silurian mafic to intermediate volcanic, volcaniclastic, and intrusive rocks of calc-alkalic to alkalic composition. The Cadia porphyry deposits are temporally and genetically associated with composite intrusive complexes of alkalic monzodiorite to quartz monzonite. U-Pb dating of igneous minerals from the intrusions and Re-Os dating of hydrothermal molybdenite from the deposits has revealed the presence of two temporally discrete events of magmatism and related porphyrystyle mineralization in the Cadia district. The monzonitic intrusive complex related to mineralization at Ridgeway and a quartz monzonite porphyry stock that lies immediately southwest of the Cadia Quarry deposit are early Late Ordovician (456-454 Ma). In contrast, the quartz monzonite porphyry stock that hosts the Cadia Quarry and Cadia Hill orebodies and an intermineral quartz monzonite porphyry dike at Cadia East are Early Silurian (~438 Ma). Re-Os molybdenite ages determined for quartz-sulfide veins within the early Late Ordovician quartz monzonite porphyry confirm multiple episodes of mineralization associated with the Cadia Quarry deposit, suggesting a complex history between 460 and 450 Ma. At Cadia Hill, Cadia Quarry, and Cadia East, a widespread event of porphyry gold-copper mineralization is recorded at about 443 to 441 Ma, based on three Re-Os molybdenite ages from sheeted quartz sulfide veins. Similar ages for magmatic zircon from the host intrusions support a link between dated intrusions and mineralization. These new ages are in general agreement with the ages of other porphyry gold-copper and related epithermal deposits of the Eastern Lachlan fold belt and help to constrain the relationship between the Cadia region and the evolution of the Lachlan fold belt. It is notable that the high-grade Ridgeway deposit is up to 18 m.y. older than any alkalic porphyry deposit yet discovered in the Macquarie arc, a feature that may be important for continued exploration success in this region.

The alkalic porphyry gold–copper deposits of the Cadia district occur in the eastern Lachlan Fold Belt of New South Wales, Australia. The district comprises four porphyry deposits (Ridgeway, Cadia Quarry, Cadia Hill, and Cadia East) and two iron–copper–gold skarn deposits (Big Cadia and Little Cadia). Almost 1,000 tonnes of contained gold and more than four million tonnes of copper have been discovered in these systems, making Cadia the world’s largest known alkalic porphyry district, in terms of contained gold. Porphyry gold–copper ore at Cadia is associated with quartz monzonite intrusive complexes, and is hosted by central stockwork and sheeted quartz–sulfide–(carbonate) vein systems. The Cadia porphyry deposits are characterized by cores of potassic and/or calc–potassic alteration assemblages, and peripheral halos of propylitic alteration, with late-stage phyllic alteration mostly restricted to fault zones. Hematite dusting is an important component of the propylitic alteration assemblage, and has produced a distinctive reddening of feldspar minerals in the volcanic wall rocks around the mineralized centers. Sulfide mineralization is strongly zoned at Ridgeway and Cadia East, with bornite-rich cores surrounded by chalcopyrite-rich halos and peripheral zones of pyrite mineralization. The Cadia Hill and Cadia Quarry deposits have chalcopyrite-rich cores and pyrite-rich halos, and Cadia Hill contains a high-level bornite-rich zone. Distinctive sulfur isotopic zonation patterns have been identified at Ridgeway, Cadia Hill, and Cadia East. The deposit cores are characterized by low δ34Ssulfide values (−10 to −4‰), consistent with sulfide precipitation from an oxidized (sulfate-predominant) magmatic fluid at 450 to 400°C. Pyrite grains that occur in the propylitic alteration halos typically have δ34Ssulfide values near 0‰. There is a gradual increase in δ34Ssulfide values outwards from the deposit cores through the propylitic halos. Water–rock interaction during propylitic alteration caused magmatic sulfate reduction and concomitant oxidation of ferrous iron-bearing minerals, resulting in enrichment of 34S in pyrite and also producing the distinctive reddened, hematite-rich alteration halos to the Cadia deposits. These results show that sulfur isotope analyses have potential applications in the exploration of alkalic porphyry-style deposits, with zones of depleted δ34Ssulfide values most prospective for high-grade mineralization.

Ridgeway is a high-grade gold-copper porphyry deposit (54 Mt at 2.5 g/t Au and 0.77% Cu), related to an alkalic intrusive complex of monzonitic composition. The deposit occurs within the Cadia district of New South Wales, Australia, which consists of a cluster of four Late Ordovician gold-copper porphyry deposits and two iron-copper-gold skarn deposits with a combined gold resource in excess of 574 metric tonnes (t). The deposits lie on a 7-km-long, northwest-oriented corridor of alteration and mineralization, transverse to the axis of the postulated volcanic arc. Alteration and mineralization at Ridgeway are zoned around a vertically attenuated intrusive complex of monzodioritic to quartz monzonitic composition. Distinct styles of veining and alteration are related to different intrusive phases of the monzonite complex, with the intensity of alteration and grade of mineralization decreasing from early- to late-mineral intrusions. Early-mineral intrusions are associated with intense actinolite- magnetite-biotite (calc-potassic) alteration and up to four stages of high-grade quartz-magnetite-sulfide veining. Bornite is the most abundant sulfide formed during early-stage alteration and correlates well with gold. Moderate- to weak-intensity orthoclase-biotite plus or minus magnetite (potassic) alteration accompanies the inter- and late-mineral intrusions, this alteration being associated with chalcopyrite- and pyrite-rich quartz-orthoclase veins. Propylitic and sodic (albite-pyrite) alteration assemblages are peripheral to, and locally overprint, the potassic alteration. Phyllic alteration is restricted to the margins of late-stage faults. The fluid inclusion assemblage comprises one and two salt-bearing brine inclusions, in addition to aqueous liquid-vapor inclusions of low to moderate salinity. No low-density, vapor-rich inclusions are present, indicating that the fluids from which the quartz veins precipitated did not enter the liquid-vapor field of the H2O-NaCl system. The brine inclusions undergo final homogenization to liquid via halite dissolution. This phenomenon, in addition to the absence of low-density vapor inclusions, suggests that the mineralizing fluids at Ridgeway were nonboiling hypersaline brines that exsolved directly from the crystallizing magma. The presence of mineralized aplitic vein dikes and comb quartz layering are interpreted to indicate that the early and transitional stages of mineralization at Ridgeway formed at the transition between magmatic and hydrothermal conditions.

Wilson AJ, Boxer MM. Neurotoxicity of Angiographic Carbon Dioxide in the Cerebral Vasculature. Invest Radiol 2002;37:542-551. RATIONALE AND OBJECTIVES. This study was undertaken to resolve conflicting evidence about the neurotoxicity of carbon dioxide gas as an angiographic contrast medium within the cerebral vasculature. MATERIALS AND METHODS. Single intracarotid injections or five consecutive intracarotid injections, at 2-minute intervals, of carbon dioxide, iopromide or saline, were given to 32 rabbits under clinically relevant conditions. Extravasation of Evans blue and 9 9 m Tc-pertechnetate was used to determine blood-brain barrier damage at 30 minutes or 6 hours after injection. At 6 hours after multiple injections, brains were removed for histologic examination. RESULTS. A single intracarotid injection of carbon dioxide caused minimal blood-brain barrier breakdown, whereas multiple injections caused significant breakdown that was still present at 6 hours after the injections. All carbon dioxide-injected brains that underwent histologic examination showed evidence of irreversible brain damage in the injected hemisphere. CONCLUSIONS. The study confirms the neurotoxicity of carbon dioxide within the cerebral vasculature and its unsuitability for clinical use in cerebral angiography.

Carbon dioxide (CO2) gas has been used clinically as an arterial contrast medium for more than 25 years. It has a number of advantages over iodinated contrast media, including its low cost, low viscosity, rapid elimination, buoyancy, and lack of nephrotoxic and allergic effects (1). Its disadvantages include the need to avoid air contamination and to use a dedicated injector system. When properly delivered and imaged, it produces images comparable to iodinated contrast media, and it is currently in use in all areas where iodinated contrast media are used, with the exception of the cerebral arterial vasculature (1). This exception is the result of concerns about the neurotoxicity of carbon dioxide in the cerebral vasculature. These concerns are based on animal studies showing severe neurotoxicity of carbon dioxide injected into the cerebral vasculature (2,3). Other animal studies, on the other hand, have been unable to demonstrate any neurotoxicity of carbon dioxide (1,4,5). Interpretation of these conflicting studies is complicated by the fact that most of them have not employed a systematic experimental approach, using different volumes, pressures, injection numbers, and injection sites within the same experiment. There are also concerns that, in some cases, the observation of neurotoxicity may have been influenced by air contamination and by high-pressure, explosive delivery of large volumes of carbon dioxide (1). It has been shown in this laboratory that multiple, nonexplosive internal carotid injections of carbon dioxide at clinically relevant doses in rabbits cause blood–brain barrier (BBB) breakdown that is still present 30 minutes later (6). This study was undertaken to investigate the reversibility of this BBB breakdown, and to examine brains for evidence of histologic damage 6 hours after multiple internal carotid injections of carbon dioxide delivered as reproducibly and benignly as possible. It is necessary to resolve the question of the neurotoxicity of carbon dioxide to determine both whether it is a safe neuroangiographic contrast medium and whether there is cause for concern about possible incidental reflux into the cerebral vasculature during carbon dioxide angiography below the diaphragm.

SUMMARY The blood, cerebrospinal fluid (CSF), and extracellular fluid of the parenchyma form the fluid compartments of the brain with three interfaces between, namely the blood–brain interface (BBB), the CSF–brain interface, and the blood–CSF interface. When either water-soluble iodinated contrast media (CM) or water-soluble paramagnetic CM are injected intravenously, they are rapidly brought into contact with both the BBB and the blood–CSF interface. It is the behaviour of the water-soluble CM at these two interfaces that determines the normal and abnormal enhancement patterns demonstrated by either CT or MRI. Unlike lipophilic solutes, current iodinated and MRI contrast media all have high affinities for plasma water, low affinities for plasma proteins and, in particular, extremely low partition coefficients. Therefore they do not penetrate the normal BBB. On the other hand, radiopharmaceuticals used in positron emission tomography (PET) and single photon emission computed tomography (SPECT) to demonstrate regional cerebral blood flow are highly lipophilic and readily cross the intact BBB completely during the first pass through the cerebral vasculature. It is the inability of the current iodinated and MRI contrast media to cross the normal intact BBB that is the basis of their use in CT and MRI studies of the brain.

Billions of dollars have been expended in foreign assistance throughout the third world, with much of this aid being provided by the not-for-profit community. While frequently effective in facilitating short-term benefits, these projects often do not improve the continuing living conditions for the residents of the community. Not-for-profits generally are in the business of short-term crisis relief; consequently, they do not have a focus on job provisions in the affected community that would increase their living standards in the long-term. Entrepreneurs, on the other hand, are in the business of job creation, which not only provides long-term benefits for the entrepreneur, but also for the entire community. Microlending, a term coined originally by Muhammad Yunus to describe very small loans made in third-world countries, has had an enormous impact on the lives of entrepreneurs, their families, and their communities. Many not-for-profits may wish to employ the techniques illustrated by Yunus and other successful microlending institutions. They may find the task overwhelming, however, without employing business professionals, whose services can be costly. For not-for-profits who might be interested in starting such a program, this paper will describe the process of microlending, articulate methods of selecting a loan recipient, and show mechanisms for documenting a microloan.

This study was performed to assess the relative contributions of contrast medium osmolality and chemotoxicity to contrast-induced blood-brain barrier (BBB) damage. Experimental carotid angiography was carried out in rabbits with mannitol at an osmolality of 714 mOsm/kg, with the nonionic, monomeric contrast media iohexol and ioversol at similar osmolalities, and with the nonionic, dimeric contrast media iodixanol and iotrolan at osmolalities less than half that of the mannitol. The amount of damage caused by the procedure was assessed by determining the amount of intracerebral extravasation of intravascularly injected technetium-99m-pertechnetate. Mannitol caused no detectable BBB damage, but all four contrast media caused BBB damage that was significantly more severe than that caused by mannitol. The BBB damage caused by carotid angiography with iohexol, ioversol, iodixanol, and iotrolan was not attributable to their osmolalities, but due to some other physical and/or chemical effects of these media on the BBB.

Langerhans cells (LCs) are dendritic, antigen-presenting cells found in the epidermis. This study investigates the effect of early breast cancer on the expression of CD1a and S100 antigens by these cells. LCs were counted and expressed as cells/mm of epithelial basement membrane on biopsies from the skin overlying the tumour and from biopsies distant from the tumour. A control study was performed on normal breast skin, not adjacent to a lesion, from women with benign breast disease. The LC count of 18 patients undergoing biopsy for benign breast disease indicated a mean of 26 cells mm [95 percent confidence interval (CI) 23–29] and a S100/CD1a ratio of 70 percent. In 35 cases of early breast cancer, the CD1a-positive LC count in the epidermis overlying the carcinoma (mean 26/mm; 95 per cent CI 23–29) was similar, but the count made on biopsies distant from the tumour (mean 21/mm; 95 per cent CI 19–23) was significantly smaller. The percentage ratio of S100/CD1a LCs was 71 per cent over the carcinoma and 84 per cent in the distant biopsies. The changes were not associated with the presence of nodal metastases or the oestrogen and progesterone status of the primary tumour. The reduction in LC numbers provides a link between decreased monocyte function and the decreased skin hypersensitivity responses found in patients with breast cancer.

Whisson CC, Evill CA, Sage MR, Wilson AJ. Effect of additional cations on the twitching reaction to intracarotid, nonionic contrast media in rabbits. Invest Radiol 1990;25:1004–1009. Previous investigations in this laboratory have confirmed the observation of facial muscle twitching during intracarotid injections of nonionic contrast media (CM) in rabbits. The reaction appears to be a locally mediated effect. To further investigate this reaction, cortical electroencephalogram (EEG) and facial electromyogram (EMG) recordings were made from rabbits receiving selective internal carotid artery (ICA) and external carotid artery (ECA) injections of CM. The effects of iopromide and iohexol were compared with and without the addition of sodium (Na) and calcium (Ca) ions at different concentrations. External carotid injections of iopromide also were performed in some animals paralyzed with D. tubocurarine to exclude the possibility that the reaction is due to an effect on peripheral nerves. The addition of between 5 and 20 mM Ca ions to both CM prevented the reaction but while the addition of Na ions (up to 150 mM) to iopromide had some preventative effect, it did not totally abolish the reaction. In those animals paralyzed with D-tubocurarine, the reaction to iopromide, as observed and recorded by EMG, was the same as that occurring in nonparalyzed animals. This finding is consistent with this reaction being independent of the peripheral nervous system.

Ed Malone. 2011. The Australasian Institute of Mining and Metallurgy, Spectrum no. 19, Victoria, Australia. 252 p. ISBN 978-1-9215522-38-3. $70 AUS (also $50 AUS in CD-ROM format). The Cadia Valley Mines: A Mining Success Story is a comprehensive account of the discovery, evaluation, development, and operation of a series of gold-copper orebodies that today comprise Newcrest Mining Limited’s Cadia Valley operations. This is a globally significant cluster of porphyry-style ore deposits hosting at least 44 Moz of gold and 8 Mt of copper, and certainly worthy of the attention to detail provided by the book’s author, the economic geologist Ed Malone. The book is laid out in 25 chapters that cover, in chronological order, a preamble on generic aspects of the Cadia district (geography, geology and mineralization, mining methods, ore reserve estimation methodologies), the pre-Newcrest exploration period, and a detailed account of the Newcrest exploration and discovery phase. This is followed by accounts, from both a technical as well as …

Carbon dioxide gas (CO2) has been in limited use in radiology as an intra-arterial, digital subtraction angiographic contrast medium for more than 20 years. It has a number of advantages over conventional iodinated contrast media, including its low cost, low viscosity, rapid pulmonary elimination, buoyancy, and lack of nephrotoxic and allergenic effects. Its disadvantages include the need to avoid air contamination and to use a dedicated injector system (Kerns et al.,1995). It has the potential to be used in all areas where iodine-containing contrast media are used, with the exception of the cerebral vasculature (Hawkins and Caridi, 1998). This exception is due to continuing concerns about the neurotoxicity of CO2 within the cerebral vessels. These concerns are due to a number of conflicting animal studies on the neurotoxicity of CO2 in the cerebral vasculature. Some studies have reported severe neurotoxicity (Coffey et al.,1984; Linstedt et al.,1997), while others have reported no neurotoxicity at all (Shifrin et al.,1990; Dimakakos et al,1998; Hawkins and Caridi, 1998). Interpretation of these inconsistent results is complicated by the fact that most have not used a systematic experimental approach, with different volumes, pressures, injection numbers and injection sites used within the same experiment. There have also been suspicions that air contamination, large volumes and explosive delivery of the CO2 may have contributed to the adverse findings (Hawkins and Caridi, 1998).

An increasing number of studies report the safety and effectiveness of carbon dioxide (CO2) as a digital subtraction angiographic contrast agent for intraarterial use below the diaphragm. Concerns about the possible neurotoxic effects of CO 2 within the cerebral circulation may be hindering its more widespread use below the diaphragm, because of the potential for reflux into the brain due to its buoyancy. These same concerns have also suppressed any consideration of CO 2 as a potential contrast agent for cerebral angiography. These concerns have been supported by a study (1) in which rats received single intracarotid injections of CO 2 in a range of doses, causing irreversible blood-brain barrier (BBB) damage and severe neurological deficits, with death occurring within 24 hours at the higher doses. Multifocal ischemic infarction was observed histologically as early as 6 hours after injection (1). Conversely, in a more recent study, dogs received multiple aortic arch and intracarotid injections of CO 2 but showed no EEG changes, no neurological deficits up to 6 months later, and no macroscopic pathological brain changes (2). There is clearly conflicting evidence about the safety of CO 2 within the cerebral circulation, and this investigation was undertaken with the intention of resolving the issue. Short-term studies were undertaken to determine the effects of intracarotid CO 2 on the BBB, and medium-term

A study has been carried out for the European Space Agency (ESA) on strategies for radiometric and spectral calibration of data produced by optical sensors observing Earth surface from Earth orbit. The study relates specifically to data produced by high-resolution imaging spectrometers and imaging radiometers, such as the PRISM instrument which is currently under development by ESA. The typical instrument specification includes 50m spatial resolution on ground, with 10nm spectral resolution through the visible/near-IR and short-wave IR spectral wavebands, plus imaging in a few selected wavebands in the thermal IR. This paper is limited to discussion of the first step in the radiometric calibration process, in which raw digitized data from the space instrument are converted to accurate values for at- sensor radiances. Relative spectral response information, for each resolved spectral band, must accompany the calibrated radiance data. The calibration process, for at- sensor radiances, requires accurate characterization of the space-instrument response characteristics. Part of the specification for the PRISM instrument is given as an example of performance requirements, and a possible design form for PRISM is briefly described as an introduction to discussion of the relevant response characteristics. Critical pre-flight and in-flight characterization requirements are noted, and methods for in-flight characterization are discussed briefly, including use of on- board hardware and space-views, and vicarious calibration using ground target areas.

We examine cultural characteristics in the context of economic affiliation and the timing of IFRS adoption. Prior work identifies cultural characteristics as key factors in the development of accounting systems world-wide. Our analysis extends this literature by showing that these same factors lead to economic clusters and to the propensity for adopting a universally accepted set of accounting rules. We contribute to the literature by demonstrating that, at least in one case, cultural factors are able to predict economic affiliations. Second, we provide evidence that certain cultural characteristic are affiliated with the delay in adoption of IFRS. Our results are valuable to local as well as international accounting standard setters as they look to negotiate common ground for convergence. Our examination of the cultural aspects distinctive in adoption patterns may provide insight into what specific aspects of the IFRS must be modified to expand and accelerate convergence.

The effects of medium conditioned by rat C6 glioma cells (C6-CM) on the survival, neurite formation, and catecholamine content of adrenal medullary cells in culture were investigated and compared with the effects of nerve growth factor (NGF). Adrenal medullary cells were isolated from 10-day-old rats and the proportions of surviving and neurite-extending cells were determined after 8 days in culture. In the presence of C6-CM virtually all seeded cells survived and 50% developed neuritic processes. In contrast, NGF did not support survival above control levels (30%) and induced neurite formation from approximately one-third of the surviving cells. C6-CM and NGF had no additive effects on neurite outgrowth. C6-CM-mediated fiber outgrowth was not inhibited by physiological concentrations of glucocorticoids which abolished the NGF-induced neurite formation. Both C6-CM and NGF increased the catecholamine content of the cultures and reduced the relative content of epinephrine. However, in view of its substantial effect on cell survival as compared to NGF, C6-CM caused a reduction of the catecholamine content per cell. We conclude that adrenal medullary cells, like other members of the sensory-sympathetic cell lineage of the neural crest, respond to glial-conditioned medium. This response differs both quantitatively and qualitatively from that mediated by NGF.

Critical fusion frequency (CFF) values for a white and three colored targets were obtained on five Ss over a wide range of scotopic and photopic luminance levels. All the target:intensity values were taken from a decibel (dB) scale of luminance whose reference level was set at 10−10 L [10−6 trolands (Tr)] of white light. The major findings indicated that (a) the obtained curves relating CFF and stimulus intensity showed discontinuities at about 47 dB (.05 Tr), the approximate value of the photopic threshold, and (b) the CFF-intensity functions for the white and colored stimuli: were coincident above the photopic threshold, while in the scotopic range the blue curve exhibited marked lateral displacement over decreasing luminance values, the red function showed no displacement from the photopic functions, and the green and white curves were intermediate between those for blue hundred. The results were compared, on the same intensity scale with the findings of two other CFF studies and with recent reaction time research which provided similar support for the predictions of the duplicity theory of vision.

A simple circuit for a sine wave generator is described. The total cost for construction is approximately $30.00. At present, the unit is used to generate a sinusoidally modulated light stimulus for steady state visual evoked response experiments. Modifications of the circuit for other applications are discussed.

In an unrestrained-choice color-naming task 26 males and 29 females responded to 21 colored chips from the Farnsworth-Munsell series. The females provided a significantly greater number of different color names for the chips than did the males. The data also showed that the leisure activities of the females were more color-dependent than those of the males. It is suggested that the observed sex differences in color-naming performance are learned differences in the expression of color appreciation.

A Westheimer-like function has been obtained for simple reaction time (RT) to target luminance increments superimposed upon homogeneous background fields. RT to a constant-luminance target progressively increases as the outer diameter of a constant-luminance background is increased up to approximately 6′–8'. Further increases in background diameter up to approximately 10′–22′ then result in progressive decreases in RT. Beyond this background diameter RT remains relatively constant. The magnitude of this effect diminishes rapidly as target luminance is increased beyond a near-threshold value.

There is very little known about the subsequent behaviour of breast cancer following adjuvant endocrine therapy or the effect of this therapy on the oestrogen and progesterone receptor content of recurrent disease. Mammary tumours were induced in Sprague–Dawley rats using n-nitrosomethylurea. In two experiments animals were treated with tamoxifen at different doses prior to the appearance of tumours. Tamoxifen prolonged the induction time and reduced the total number of tumours. Subsequent treatment of established tumours exposed to tamoxifen in the induction period demonstrated a reduced response to further tamoxifen therapy. There was no difference in the oestrogen receptor content of the tumours previously exposed to tamoxifen, but there was a significant reduction in the progesterone receptor content. The results suggest that: (a) patients treated with adjuvant tamoxifen therapy will show a delay in the appearance of recurrent disease with a reduced response to further tamoxifen therapy; (b) the model may provide an in vivo method to examine the relationships between oestrogen and progesterone receptors and response to endocrine therapy.

Correlated experiments on visual reaction time (RT) and visual evoked cortical potentials (VECP's) were performed to assess the effects of illumination level of steady annulus surrounds on the latency of response to centrally presented target flashes (1 and 3 degrees in diameter) over a wide range of retinal illuminances. The latencies of the electrophysiological (VECP) responses are more variable than those of the psychophysical RT responses. For both classes of response, the visual latency for a given target flash luminance is systematically increased (inhibited) by a spatially contiguous annulus with a retinal illuminance that equals or exceeds that of the target. The inhibitory effect of a given annulus increases progressively as the target retinal illuminance is lowered below that of the annulus. The corresponding RT and VECP curves have the same shape, thus suggesting that the motor component of the RT responses is not differentially influenced by variations in target illumination. The inhibitory effects are characteristically greater for the 3 degrees target than for the 1 degree target. Lateral neural inhibition and stray-light models for these data are considered.

A simple circuit for a digital millisecond timer and event counter is described. The total cost of the unit including all components, a power supply, and an enclosure is less than $30. Daily use in simple reaction time experiments has demonstrated the reliability of the design.

(1975). Economic Theory and the Construction Industry. Journal of the Operational Research Society: Vol. 26, Volume 26, issue 3, pp. 574-575.

A simple circuit for a keyed tone generator is described. The total construction cost is less than $5. Various adaptations and modifications of the circuit are discussed.

While some computer center libraries include programs that perform comparisons for multifactor analysis of variance (ANOVA) designs, these programs are usually limited to designs with equal cell Ns. Program UMAVC extends these basic capabilities to include factorial designs with unequal cell Ns (Keppel, 1973; Myers, 1972). The program employs unweighted means techniques to assess comparisons for main effects (example: Acomp) and for interactions (example: Acomp by B by C). Description. This program consists of two major segments. The first segment performs one-, two-, three-, or four-way unweighted means ANOVAs for standard factorial designs (fixed effect only) having either equal or unequal cell Ns; this program segment is similar in design to Veldman's (1967) AVAR23 program. The second segment performs comparisons requested by the user. These comparisons may be orthogonal or nonorthogonal, or tests for trend depending upon the coefficients that are specified. Input. Three program control cards precede the data: an ANOVA problem identification card, an ANOVA design card, and a data format card. The data is read in accordance with the user-specified format and is arranged with the subscript of the last factor varying the fastest. Cards containing the cell Ns are placed before each "cell" of data cards. A card containing the comparison problem identification immediately follows the data. Cards specifying the desired comparisons and their coefficients complete the deck setup. Output. Output from UMAVC consists of (l) a standard unweighted means ANOVA table including the probabilities of the computed F ratios, (2) cell means and cell Ns, and (3) a comparison table including sums of squares, degrees of freedom, mean squares and F ratios accompanied by their associated probabilities. Restrictions. The number of levels of each ANOV A factor must not exceed 10. The program can analyze only one comparison per factor in a given run; different comparisons for different factors may be analyzed in a single run. In the case of trend comparisons, for example, to investigate both linear and quadratic trends for factor A would require two runs, while a linear trend for factor A, a quadratic trend for factor B, a cubic trend for factor C, and a quartic trend for factor D could be investigated in a single run. Computer and language. The program is written in FORTRAN IV and was developed on an IBM 370{155 with virtual memory. It executes in approximately 192K of core; reducing the maximum number of levels for the ANOV A factors below the present value of 10 would greatly reduce the program's core requirements. Compilation time is approximately 30 sec. Data sets of average size may be analyzed in 5-10 sec of CPU time. Two direct access devices are required. The program consists of a mainline and 13 subroutines. Availability. A documented listing of UMAVC is available at no cost from the first author at: Southern College of Optometry, 1245 Madison Avenue, Memphis, Tennessee 38104.