Fluctuations in measured radioactive decay rates inside a modified Faraday cage: Correlations with space weather.

For several years, reports have been published about fluctuations in measured radioactive decay time-series and in some instances linked to astrophysical as well as classical environmental influences. Anomalous behaviors of radioactive decay measurement and measurement of capacitance inside and outside a modified Faraday cage were documented by our group in previous work. In the present report, we present an in-depth analysis of our measurement with regard to possible correlations with space weather, i.e. the geomagnetic activity (GMA) and cosmic-ray activity (CRA). Our analysis revealed that the decay and capacitance time-series are statistically significantly correlated with GMA and CRA when specific conditions are met. The conditions are explained in detail and an outlook is given on how to further investigate this important finding. Our discovery is relevant for all researchers investigating radioactive decay measurements since they point out that the space weather condition during the measurement is relevant for partially explaining the observed variability.

Simultaneous analysis of neutral and acidic pharmaceuticals as well as related compounds by gas chromatography-tandem mass spectrometry in wastewater.

This work presents a new multi-residue analytical method based on solid phase extraction (SPE) with Oasis HLB sorbent, followed by gas chromatography tandem mass spectrometry (GC-MS/MS) for the simultaneous determination of a group of 10 acidic and neutral pharmaceuticals and related compounds in wastewaters. The typical derivation step was avoided, allowing the determination of acidic and neutral pollutants in a single analysis as well as providing a fast and easy method suitable for routine monitoring. Target pollutants include: anti-inflammatory drugs (ibuprofen, acetaminophen and diclofenac); an antiepileptic agent (carbamazepine); stimulants (caffeine and nicotine); an antiseptic (triclosan); a plasticizer (bisphenol A) and two of their more relevant metabolites (2,8-dichlorodibenzo-p-dioxin and 1,7-dimethylxanthine). Recoveries between 66 and 112% were achieved for all the target compounds (except for 2,8-dichlorodibenzo-p-dioxin). Good linearity was observed within the studied ranges (R(2)>0.993). Acceptable intra and inter-day precision was obtained, with relative standard deviation between 2 and 18%. The application of the optimized MS/MS mode allowed method detection limits in the range of 0.2-16ng/L, with the exception of ibuprofen (120ng/L). Finally, the methodology was successfully applied to the analysis of hospital effluent samples. All target analytes were detected at concentrations between 1ng/L and 83215mug/L. Even in the absence of derivatization, all the analytes showed good peak shape, except acetaminophen, which exhibited peak tailing. However, the method proved to be repetitive and reproducible, and the peak shape did not represent a problem for the reliable quantification of this compound. For most of the analytes studied, the detection limits achieved compare well against values reported in previously published methods.

Application of gas chromatography-hybrid chemical ionization mass spectrometry to the analysis of diclofenac in wastewater samples.

Hybrid chemical ionization (HCI), a new and useful alternative to conventional chemical ionization mass spectrometry, has been applied to the analysis of the pharmaceutical diclofenac in wastewater samples. This technique takes advantage of the high versatility of ion trap (IT) spectrometers combined with external ionization sources. In hybrid configuration, reagent ions are generated in the external source through electron ionisation (EI) of a reagent gas. These reagent ions are then drawn into the ion trap and only those selected are allowed to react with analytes eluting from the GC column. These ion-molecule reactions create analyte ions which are held in the ion trap. In this study ion-molecule reactions between C(3)F(5)(+) cations, generated from perfluorotributylamine (FC43), and diclofenac molecules have been investigated. The observed reaction products were [M+C(3)F(5)-H(2)O](+) adduct ions, which result from the initial electrophilic addition of C(3)F(5)(+) cations to the diclofenac molecule followed by the rapid loss of H(2)O. Further fragmentation of these ions by MS/MS yielded enough daughter ions for a reliable identification of diclofenac in complex matrices. The GC-HCI-MS/MS method applied to wastewater samples provided highly enhanced selectivity and sensibility, with a detection limit in real samples of 3.0 ng/L, for a solid-phase extraction (SPE) pre-concentration factor of 400. Other performance characteristics of the method, such as linearity and precision were also satisfactory. Finally, the method was successfully applied to the analysis of wastewater samples taken from the effluent of an urban sewage treatment plant (STP).

Multiresidue determination of pesticides in fruit and vegetables by gas chromatography/tandem mass spectrometry.

Pesticide residues in fruit and vegetables were determined by gas chromatography/tandem mass spectrometry (GC/MS/MS). Electron impact (EI)/MS/MS and chemical ionization (CI)/MS/MS were developed for 80 compounds, including organochlorine, organophosphorus, organonitrogen, and pyrethroids, providing unambiguous spectral confirmation for these complex matrixes. Residues were extracted from samples with acetone followed by a mixture of dichloromethane-petroleum ether. Two injections per sample were required for analysis of the entire pesticide list by EI/MS/MS and CI/MS/MS. Initial steps involving cleanup and concentration of extracts were eliminated. The excellent selectivity and good linearity allowed quantification and identification of low levels of pesticides in the most difficult matrixes. The method has been used for routine analysis of many vegetables.

[Hypertrophic osteoarthropathy in a patient with nasopharyngeal carcinoma]. / Osteoartropatía hipertrófica en paciente con carcinoma de nasofaringe.

A clinic-pathological study of a 12 year-old male diagnosed of non-differentiated nasopharyngeal carcinoma (NPC) was carried out. The patients presented secondary hypertrophic osteoarthropathy prior to the development of lung metastases. Hypertrophic osteoarthropathy is a clinic-radiological syndrome characterized by a neoformation of periosteal bone, fundamentally located in long bones and distal ends of metacarpal bones. Polyarticular and synovial involvement is also observed. Association between NPC and hypertrophic osteoarthropathy is uncommon and appears to suggest the existence of metastatic spread (probably to the lung), particularly in young patients.