Atmospheric pressure thermal desorption chemical ionization mass spectrometry for ultra-sensitive explosive detection.

Illegal explosives are a threat to aviation, transport sector, critical infrastructure and generally to public safety. Their detection requires extremely sensitive instruments with efficient workflows that allow large throughput of items. In this study, we built a trace explosives detection instrument that requires minimal sample treatment and reaches ultra-low picogram level detection limits for many common explosives. The instrument is based on thermal desorption of filters, which allows analysis of liquid and solid phase samples, and subsequent selective atmospheric pressure chemical ionization and detection with a mass spectrometer. We performed experiments to scope the optimal ionization chemistry for the system and selected Br- as the reagent ion, and measured the limit of detection for 14 different explosives that were generally in the picogram range. Finally, we demonstrate the usability of the system by sampling air to a filter from a storage room known to contain explosives, from which we detect four different explosives.

[Course of Severe COPD with and without Physiotherapy with the RC-Cornet(R)]. / Krankheitsverlauf bei schwerer COPD mit und ohne Physiotherapie mit dem RC-Cornet(R) - Eine randomisierte 2-Jahres-Langzeitstudie.

UNLABELLED: The efficacy of respiratory physiotherapy by combined-PEP (RC-Cornet(R) in combined-PEP-position) was evaluated in a long-term study with the following set up. STUDY DESIGN: Randomized prospective clinical trial over 2 years in 50 patients with severe COPD (12 f, 38 m, 63,1 y, FEV 1 41 %, DLCO 51 % of the normal). Patients were without infection and exsmokers at begin of the trial. One group was treated only by drug therapy (theophylline, salmeterol, ipratropiumbromide, systemic steroids 5 mg prednisolone equivalent). The second group received the same drug therapy plus physical therapy with the RC-Cornet(R) (oscillating PEP; in combined PEP-position) 3 times daily at least for 5 minutes or whenever needed. Lung function data were controlled every 3 month during first year and every 4 month in the second year. The compliance was checked by theophylline and cortisol blood levels, inspection of the functionality of the RC-Cornet(R) and by questioning the patient about compliance with the therapy. RESULTS: TGV (% of normal) and airway resistance (measured by bodyplethysmography) decreased significantly in contrast to the "mere" drug therapy (p < 0.0177, p < 0.0179). VC (% of normal) increased significant p < 0.0179 in the RC-Cornet(R) therapy group. In this group significantly less patients (13/24) needed antibiotics in comparison to the "mere" drug group (Chi-Quadrat p < 0.0004). Also the need for hospital care was significantly less in the RC-Cornet(R) group (5/12) in comparison to the drug therapy group (Chi-Quadrat < 0.000765). The length of hospital stay in the two groups was not significantly different: 16.2 +/- 6.3 days in the RC-Cornet(R)-group and 18.3 +/- 4.7 days in the drug therapy-group. CONCLUSION: This study proves the efficacy of respiratory physiotherapy with combined-PEP in addition to drug therapy in the management of COPD-patients.