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Dibrominated bis[1]benzothieno[3,2-b;2',3'-e][1,4]thiazines (BBTT) are efficiently synthesized and applied in Suzuki and Buchwald-Hartwig cross-coupling reactions to give access to 3,9-disubstituted BBTT derivatives with extended π-conjugation and enhanced electronic properties. For instance, 3,9-di(hetero)aryl substituted BBTT derivatives surpass their parent congeners phenothiazines with lower oxidation potentials and pronounced yellow to orange-red fluorescence (Φf ≈ 30-45%). In addition, 3,9-bis(di(hetero)arylamino substituted BBTT possess very high lying HOMO energy (EHOMO = -4.46 to -4.83 eV), a favorable property of hole transport molecules. A representative X-ray structure analysis reveals that the central BBTT core in these extended π-systems is essentially planarized. Upon protonation of a 3,9-bis(di(hetero)arylamino) substituted BBTT, the absorption color shifts from yellow to deep blue with a concomitant loss of the emission. The optical properties of these novel BBTT derivatives can be plausibly rationalized by time-dependent density functional theory (TD(DFT)) calculations and correlation between experimentally determined oxidation potentials and σp parameters as well as between photophysical data and the specific substituent parameter σp- by establishing electronic structure-property relationships.

Dibrominated bis[1]benzothieno[3,2

4-Pyrazolyl-1,2,3-triazoles can be readily synthesized in a one-pot fashion and moderate yield by employing a consecutive four-component process consisting of a sequentially Pd-Cu-catalyzed alkynylation-cyclocondensation-desilylation-CuAAC process. Most distinctly, (triisopropylsilyl)butadiyne is employed as a four-carbon building block in this one-pot de novo formation of both heterocyclic moieties.

This paper examines the potential of using the FDHEM RESOLVE system as basis for mapping reaches of the river that contribute to elevated salt loads in the Murray River to the south east of Mildura in Victoria. The advantages of the airborne systems become more apparent when data coverage and acquisition costs are considered, particularly in a situation where a parallel swath approached is employed. This entails the acquisition of adjacent lines of EM data along the centre and along the margins of the river. We suggest this approach provides for a better understanding of recharge and discharge processes and links between the floodplain and the main-river channel. Compared with data acquired along the river alone, this study demonstrated our ability to use Helicopter EM data to map losing and gaining (from a salt load perspective) stretches of the river and to provide insight into which parts of the groundwater-floodplain system were significant contributors to river salt loads. The rapid acquisition of airborne EM data makes these systems more suited to providing temporal snapshots of a river-floodplain environment during dramatic climatic events, such as flooding.

Accurate, high resolution images of the top 10 to 50 metres of the earth’s surface potentially provide insights into the underlying hydrogeology that help us to understand, for example, the distribution of saline groundwater in the subsurface, or subtle changes in the distribution of clays in the top ten metres. This paper reviews the use of a commercially available fast-sampling TEM system in use in the surrounds of the River Murray system in southeastern Australia. This system has been used to collect data in a fairly standard TEM mode, i.e. discrete stations at fixed intervals along a line. Additionally results are shown using the system in a modified configuration, with much smaller transmitting and receiving antennae towed behind a boat, for example, with data collected in conjunction with a GPS in a “continuous” mode. This type of data provides a continuous electrical cross section with data points as close together as five metres apart, to a depth of at least ten metres.

Floodplains play an important role in catchment hydrology, representing a zone in which groundwater is shallow, and groundwater atmosphere interactions through evapotranspiration (ET) are more pronounced. Spatial patterns in evapotranspiration develop due to the variable distribution and type of floodplain sediments, patterns of vegetation type, floodplain elevation and geometry. Where groundwater is saline, as in the lower River Murray in South Australia, evapotranspiration concentrates salt and can lead to floodplain salinisation, vegetation dieback or health decline. Modelling these systems can assist our understanding of which areas of vegetation are at high risk from salinisation in order to target them for management. However, models of this scale require detailed data for parameter population and validation. Geophysical, particularly electrical, methods have the potential to provide detailed spatio-temporal information on the distribution of salinity in soils and groundwater, thereby assisting our understanding of floodplain processes that characterise the lower River Murray, in South Australia. In this paper we review this potential, and examine the relative merits of high resolution airborne electromagnetic technologies, and consider the relative performance of the RESOLVE frequency domain helicopter EM (FDHEM) and the SkyTEM time domain helicopter EM (TDHEM) systems for defining variations in near surface conductivity and sediment salt load across the Bookpurnong Floodplain. Results from coincident surveys are reviewed as are strategies for the inversion of these data. Data are examined against available borehole information including sediment chloride content and groundwater conductivity.

Geophysical methods are used in Australia to provide detailed spatial information to help predict the impact of current and future irrigation developments, the design of salt interception schemes and protection of floodplain values. RESOLVE frequency domain helicopter electromagnetic data were acquired over the Chowilla Floodplains, in the Lower Murray region of southern Australia, to provide detailed baseline data on the spatial distribution of near-surface salt stores and materials in the floodplain and their relationship with in-river salinity. Degradation across the floodplain and wetlands has resulted primarily from a significant reduction in flood events, and overgrazing. Restoration of the floodplain will involve the reduction of salinity flow from groundwater into the river and increasing environmental flows across the floodplain. Conductivity models predicted from HEM data help identify local recharge and discharge areas, and links with river salinity. The baseline data provided by the airborne data are used with high resolution ground EM surveys including EM31 and time-domain EM, over targeted areas. Ground methods can be repeated, to monitor affects of artificial flooding designed to restore vegetation health. Similarly the combination of airborne and ground data, allows piezometers to be effectively targeted with the resulting information interpreted within the context of the baseline conductivity structure defined form airborne data.

Floodplains play an important role in catchment hydrology, representing a zone in which groundwater is shallow, and groundwater atmosphere interactions through evapotranspiration (ET) are more pronounced. Spatial patterns in evapotranspiration develop due to the variable distribution and type of floodplain sediments, patterns of vegetation type, floodplain elevation and geometry. Where groundwater is saline, as in the lower River Murray in South Australia, evapotranspiration concentrates salt and can lead to floodplain salinisation, vegetation dieback or health decline. Modelling these systems can assist our understanding of which areas of vegetation are at high risk from salinisation in order to target them for management. However, models of this scale require detailed data for parameter population and validation. This paper discusses the potential application of airborne, ground and “inriver” electromagnetic techniques to indicate spatial patterns of groundwater evapotranspiration and baseflow from a salinising floodplain on the lower River Murray. High resolution RESOLVE frequency domain helicopter EM data are examined along with ‘in river’ NanoTEM and ground EM31 data. Their study demonstrated the scale of variations in baseflow was smaller than expected, showing alternation between losing and gaining (from a salt load perspective) groundwater in a river broadly understood to be a gaining system. The HEM and ground data sets are strongly correlated with groundwater salinity and are now being trialed as a basis for validating groundwater models.

Two new cases of air in the stomach wall have been described. One case presented with the typical findings of interstitial gastric emphysema. The second case demonstrated the usual clinical and pathologic criteria of emphysematous gastritis but presented an atypical roentgenographic picture. Linear air densities in the stomach wall associated with air in the portal system are described for the first time in a case of emphysematous gastritis.

Metastatic pulmonary nodules from a well-differentiated hepatoma were well demonstrated by a Tc-99m-labeled hepatobiliary imaging agent. Uptake of this type of radionuclide by metastases from a primary hepatic malignancy has not previously been reported. Such radiopharmaceuticals may prove useful in the future as imaging agents for primary hepatobiliary tumors.

Metastatic carcinoma to the thyroid gland rarely is encountered in clinical practice; however, autopsy series have shown that it is not a rare occurrence. A case of adenocarcinoma of the colon with metastases to the thyroid is reported. A review of the literature reveals that melanoma, breast, renal, and lung carcinomas are the most frequent tumors to metastasize to the thyroid. Metastatic disease must be considered in the differential diagnosis of cold nodules on radionuclide thyroid scans, particularly in patients with a known primary.

The value of 67 Ga-citrate scanning in cases of gastrointestinal malignancies is discussed. Seven cases are presented, including lymphomas of the stomach, small bowel, and rectum, and adenocarcinomas of the stomach and colon. In a review of the literature, there is general pessimism regarding the use of 67Ga scans in GI malignancies. Based on previous reports and our own experience, specific clinical situations are cited in which the scan is of considerable value for diagnosis and followup of GI malignancy.

Metastatic serosal and omental implants from a primary papillary endometrial carcinoma were well demonstrated by radionuclide uptake on a bone scan utilizing 99mTc-methylene diphosphonate. Imaging of an endometrial malignancy by a 99mTc-labeled phosphate compound has not previously been reported. While the exact mechanism of accumulation in such soft-tissue neoplastic foci is not known, several possibilities have been suggested. In this particular case, the mechanism appears related in some way to the presence of dystrophic calcifications within the metastatic deposits.

Pulmonary cryptococcosis may present in many forms. In a case recently treated in this hospital, there was total consolidation of an upper lobe with complete occlusion of the upper lobe bronchus, a pattern which has not previously been reported in this disease. The differential diagnosis of lobar consolidation ordinarily includes primary bronchogenic carcinoma, bacterial pneumonia and tuberculosis. Among the fungal diseases, coccidiomycosis, actinomycosis, blastomycosis and nocardiosis may occasionally present with lobar consolidation (Wolfe and Jacobson, 1958).

Key to the effective management of natural ecosystems that characterise the floodplains of the Murray Basin in south eastern Australia, and maintenance of river health (a critical water resource) in a setting where severe salinisation is an ever-present threat, requires a sound understanding of surface water-groundwater processes. This paper presents results from an examination of hydrogeophysics, specifically airborne electromagnetics (AEM) data acquired by the SkyTEM time domain helicopter EM system, as a means for improving our knowledge of spatial patterns associated with inter-aquifer mixing where groundwater flow is complex. In the south-eastern part of the Murray Basin, AEM data shows considerable promise as a means for understanding of groundwater quality and its lateral variability. In the Bookpurnong and Loxton irrigation areas the high moment capability of SkyTEM permits us to investigate variations in the quality of groundwater at depth (>100m), which in turn allows us to visualise how groundwater may be moving across aquitards and within particular aquifer systems.