Absolute high spectral resolution measurements of surface solar radiation for detection of water vapour continuum absorption

Solar-pointing Fourier transform infrared (FTIR) spectroscopy offers the capability to measure both the fine scale and broadband spectral structure of atmospheric transmission simultaneously across wide spectral regions. It is therefore suited to the study of both water vapour monomer and continuum absorption behaviours. However, in order to properly address this issue, it is necessary to radiatively calibrate the FTIR instrument response. A solar-pointing high-resolution FTIR spectrometer was deployed as part of the 'Continuum Absorption by Visible and Infrared radiation and its Atmospheric Relevance' (CAVIAR) consortium project. This paper describes the radiative calibration process using an ultra-high-temperature blackbody and the consideration of the related influence factors. The result is a radiatively calibrated measurement of the solar irradiation at the ground across the IR region from 2000 to 10 000 cm(-1) with an uncertainty of between 3.3 and 5.9 per cent. This measurement is shown to be in good general agreement with a radiative-transfer model. The results from the CAVIAR field measurements are being used in ongoing studies of atmospheric absorbers, in particular the water vapour continuum.

The effect of poisoned and notional vaccinated buffers on possum (Trichosurus vulpecula) movements: minimising the risk of bovine tuberculosis spread from forest to farmland

Context. Vaccination of brushtail possums (Trichosurus vulpecula) has been proposed as a cost-effective alternative to lethal control for preventing potentially bovine tuberculosis (Tb)-infected possums from crossing forested buffer zones that abut farmland. Aim. Evaluation of these two management option requires an estimation of the buffer width required to reduce the risk of disease spread to an acceptable level. Methods. The movements of two groups of adult and subadult possums were monitored for up to 12 months in the Kaimanawa Range, North Island of New Zealand, using GPS technology. One group was in untreated forest immediately adjacent to a recently poisoned forest buffer, and the second group was 2 km further into untreated forest, which mimicked a vaccinated buffer with no reduction in possum abundance. Key results. Close to the poisoned buffer, where the initial population density was 0.49–1.45 ha–1, adult possum home ranges averaged 10.2 ha in the summer immediately after control and 9.5 ha in the following winter. Two kilometres into the untreated forest, where the density was >3 ha–1, the corresponding values were only 3.5 ha and 2.8 ha. Over the first 6 months of monitoring, a ~350-m wide poisoned buffer would have contained 95% of movements by adult possums, as well as movements by most individuals, but a ~150-m wide vaccinated buffer would have been as effective. Equivalent results for the subsequent 6-month period were ~450 m and ~200 m for poisoned and vaccinated buffers, respectively. Movements by possums were not biased in the direction of the population ‘vacuum’ created by the poisoning operation. When subadult possums were included in the analysis, buffer widths of ~500–600 m for both poisoning and vaccination would be required to contain 95% of new den site locations. Conclusions and implications. Detailed data on possum movements provide a means for agencies managing Tb to specify the width of a buffer, subject to an acceptable level of risk that it could be breached by a potentially infected possum. As well as depending on the width of a treated buffer, the final cost-effectiveness of vaccination compared with poisoning will depend on the relative cost of applying the two control techniques, and the frequency of application required either to prevent Tb from establishing (in the case of vaccination) or to suppress possum density (in the case of lethal control).

Durable responses with the antiangiogenic metronomic regimen RT-PEPC in elderly patients with recurrent mantle cell lymphoma (MCL)

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Background: Targeting tumor microenvironment and angiogenesis is a novel therapeutic strategy in lymphoma. Two putative anti-angiogenic regimens, RT (rituximab with thalidomide) and PEPC oral metronomic chemotherapy (prednisone, etoposide, procarbazine and cyclophosphamide) are clinically active. We report phase II safety, activity, and angiogenic profiling data with the novel combination RT-PEPC in elderly patients with recurrent MCL. Methods: RT-PEPC includes an induction phase (mo 1–3) of daily thalidomide (50 mg) and PEPC with weekly rituximab x 4. A maintenance phase (mo 4 until progression) continues with daily thalidomide (100 mg), PEPC dosing titrated to ANC > 1K/ul, and rituximab q 4 months. Endpoints included safety, efficacy, and FACT-G quality of life (QoL) assessment. Translational studies assessed the angiogenic phenotypes of tumor cells, and dynamic levels of circulating endothelial and hematopoietic progenitors in response to treatment. Results: Twenty-five pts (19 males) were enrolled, with 22 evaluable (3 never received rx). At study entry, median age (N=25) was 68 yrs (range 52–81), 24 (96%) had stage ≥ III, 16 (64%) had LDH > nl, and 18 (72%) IPI 3–5. The median number of prior therapies was two (range 1 to 7), and 15 pts (60%) progressed on bortezomib. At a median followup of 30 months, overall response rate was 73% (32% CR/CRu, 41% PR, N=22). Median PFS was 12 months, and median OS 22 months. Four CRs of 4+, 28+, 46+ and 48+ months are ongoing. Toxicities included gr 1–2 fatigue, rash and neuropathy as well as cytopenias (by design) including gr 1–2 thrombocytopenia (56%) and gr 3/4 neutropenia (56%). Two thrombotic events and 5 episodes of gr 3–4 infection were observed. QoL was maintained or improved on treatment. Correlative studies demonstrated pre-therapy autocrine angiogenic loop in tumor cells evidenced by expression of VEGFA and VEGFR1. Circulating levels of hematopoietic and endothelial progenitor cells decreased on rx in responders. Conclusions: RT-PEPC has significant and durable clinical activity in MCL, with manageable toxicity and maintained QoL. Novel low-intensity anti-angiogenic approaches warrant further evaluation in MCL and other NHL subtypes, potentially as initial therapy in elderly patients.

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Operational impact of DDT reintroduction for malaria control on Anopheles arabiensis in Mozambique

ABSTRACT With the increase in indoor residual spraying in many internationally and nationally funded malaria control programs, and affirmation by World Health Organization (WHO) that DDT is appropriate for use in the absence of longer lasting insecticide formulations in some malaria endemic settings, DDT has been reintroduced as a major malaria control intervention in Africa. Indoor residual spraying with DDT was reintroduced into Mozambique for malaria control in 2005, and it is increasingly becoming the main insecticide used for malaria vector control in Mozambique. The selection of DDT in Mozambique is evidence-based, taking account of the susceptibility of Anopheles arabiensis (Patton) and Anopheles gambiae (Giles) s.s. to all the available insecticide choices, as well as relative costs of the insecticide and the logistical costs of spraying. Before this time in Mozambique, DDT was replaced by h-cyhalothrin in 1993. Resistance occurred quickly to this insecticide, and in 2000 the pyrethroid was phased out and the carbamate bendiocarb was introduced. Low-level resistance was detected by biochemical assay to bendiocarb in 1999 in both Anopheles funestus (Giles) and An. arabiensis, although this was not evident in WHO bioassays of the same population. In the 2000-2006 surveys the levels of bendiocarb resistance had been selected to a higher level in An. arabiensis, with resistance detectable by both biochemical and WHO bioassay. The insecticide resistance monitoring program includes assessment of field populations by standard WHO insecticide susceptibility assays and biochemical assays. Monitoring was established in 1999, and it was maintained as part of an operational monitoring and evaluation program thereafter.

Combined PET and low-dose, noncontrast CT scanning obviates the need for additional diagnostic contrast-enhanced CT scans in patients undergoing staging or restaging for lymphoma

BACKGROUND

Positron emission tomography (PET) is more accurate than computed tomography (CT) in staging and restaging of lymphoma, but both are considered necessary. Increasingly, PET is carried out with a low-dose CT scan. Many patients undergo both PET/CT and standard diagnostic CT. The clinical utility of performing both studies in patients with lymphoma was evaluated.

PATIENTS AND METHODS

Patients with lymphoma who underwent concurrent PET/CT and diagnostic CT (a scan pair) were identified, and findings detected in either scan but not both were documented. Discrepancies were considered significant if they were related to either lymphoma or another disease process which potentially required intervention.

RESULTS

Eighty-seven scan pairs were identified. PET/CT detected additional lesions over diagnostic CT in 30 patients, of which 11 demonstrated increased clinical stage. Lymphoma therapy changed based on PET/CT in two patients, and one occult rectal cancer was detected. In contrast, diagnostic CT detected five relevant findings, including two incidental findings (venous thrombosis) and three patients with splenic lesions, none of which could be confirmed as lymphoma. No patient had change of stage or lymphoma therapy based on diagnostic CT.

CONCLUSION

In our series, diagnostic CT did not add value to staging or restaging of lymphoma when carried out concurrently with PET/CT.