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In this paper, the dosimetry of small animals arranged on a monopolar patch antenna for bioelectromagnetic experiments is reported. Numerical simulations were carried out to verify the matching of the antenna in the presence of a dielectric box to accommodate the small animals. This strategy, reducing the dielectric differences between the various irradiated materials, improves largely the efficiency of the setup. The induced electric field in the biological samples reached tens of V/m for an input voltage of 1 V, which is one of the highest efficiency obtained so far for these types of exposure setup. A very short electric pulse (on-time duration of 1 ns) is transferred mostly undistorted to the biological sample guaranteeing controlled experimental exposure conditions. Optimization of the positioning of the small animals was also analyzed. Our setup can be used to study effects of short and intense electric pulses in vivo only poorly addressed so far. © 2018 Institution of Engineering and Technology.All Rights Reserved.

Klebsiella oxytoca causes opportunistic human infections and post-antibiotic haemorrhagic diarrhea. This Enterobacteriaceae species is genetically heterogeneous and is currently subdivided into seven phylogroups (Ko1 to Ko4 and Ko6 to Ko8). Here we investigated the taxonomic status of phylogroups Ko3 and Ko4. Genomic sequence-based phylogenetic analyses demonstrate that Ko3 and Ko4 formed well-defined sequence clusters related to, but distinct from, Klebsiella michiganensis (Ko1), K. oxytoca (Ko2), K. huaxiensis (Ko8), and K. grimontii (Ko6). The average nucleotide identity (ANI) of Ko3 and Ko4 were 90.7% with K. huaxiensis and 95.5% with K. grimontii, respectively. In addition, three strains of K. huaxiensis, a species so far described based on a single strain from a urinary tract infection patient in China, were isolated from cattle and human feces. Biochemical and MALDI-ToF mass spectrometry analysis allowed differentiating Ko3, Ko4, and Ko8 from the other K. oxytoca species. Based on these results, we propose the names Klebsiella spallanzanii for the Ko3 phylogroup, with SPARK_775_C1T (CIP 111695T and DSM 109531T) as type strain, and Klebsiella pasteurii for Ko4, with SPARK_836_C1T (CIP 111696T and DSM 109530T) as type strain. Strains of K. spallanzanii were isolated from human urine, cow feces, and farm surfaces, while strains of K. pasteurii were found in fecal carriage from humans, cows, and turtles. MEDVETKLEBS, MedVetKlebs

This scoping review explores circumstances surrounding the decision about, and eventual experience of, transitioning older adults into alternative levels of housing (ALH), such as long-term care. This topic is examined from a family member perspective, given their exposure and involvement in the care of older adult relatives during this transitional period. The scoping review methodology is based on the framework of Arksey and O’Malley and subsequent recommendations from Levac, Colquhoun, and O’Brien. Approximately 470 articles were reviewed covering the period between 2000 and November 2014; 37 articles met inclusion criteria. A temporal organization of themes was used to describe the experiences of family members in the pretransition, active transition, and posttransition periods of moving older adult relatives into ALH. This paper highlights the transitional period as a time of crisis, with a lack of planning, support, and transparent discussion. This study identifies a need for future research on the potential benefits of family support groups, interim transitional housing options, different models of ALH, changing roles in the posttransition period, and the need for a comprehensive list of housing options for older adults. Results have the potential to inform policy/practice and improve the lives of older adults and their family.

Il "metodo del picco ponderato" è attualmente alla base dell'approccio suggerito dalle Linee Guida ICNIRP e dalla Direttiva Europea 2013/35/UE per la valutazione dell'esposizione occupazionale a campi elettromagnetici con forma d'onda non sinusoidale, in riferimento alla prevenzione degli effetti di stimolazione. L'esperienza accumulata dal nostro gruppo in diversi anni di utilizzo, soprattutto in relazione ad alcune tipologie di sorgenti in ambito lavorativo, ha portato ad evidenziare alcune criticità del metodo, legate alla modalità con cui si procede alla sua applicazione. Il metodo può infatti essere applicato, in software, sia nel dominio del tempo, sia nel dominio della frequenza. Poiché i due approcci non forniscono sempre gli stessi risultati, ci si è posti l'obiettivo di indagare le possibili cause delle differenze, utilizzando forme d'onda realizzate ad hoc al fine di evidenziare le peculiarità di ciascun approccio.

The magnetic wireless power transfer (WPT) technology represents a promising application in contactless electric vehicle battery charging systems. In this framework, a bench prototype of resonant type, delivering a power of 560 W at 85 kHz, suitable for charging the batteries of a city car, was designed and realized. Identical transmitting and receiving resonant coils, equipped with ferrite cores, were realized in a spiral configuration. The single coil and the coupled system were experimentally characterized in terms of inductance and mutual inductance for dimensioning the resonance circuit. Measurements of the stray electromagnetic fields (EMFs) emitted by the prototype were performed, in order to assess the exposure levels at which operators, working in proximity of the bench prototype, will be subjected. Results evidenced that, for this prototype, both measured electric (E) and induction magnetic (B) fields are compliant with the European Directive 2013/35/EU, in which minimum health and safety requirements regarding the EMFs exposure of operators are established. Yet, it is worth noting that measured E field (maximum 127.8 ± 3.1 V/m) was not compliant with the exposure limit established by the European Recommendation (1999/519/CE) for the population (83 V/m). As consequence, it should be necessary to characterize the stray EMFs in the actual exposure scenario, with the system directly mounted on the city car. Moreover, the exposure assessment of wireless systems delivering higher powers (some kW) should be required, also foreseeing numerical dosimetry to assess the induced E field within the human body. © 2015 EurAAP.

Recently, the use of liposomes loaded with magnetic nanoparticles (magnetoliposomes, (MLs)) has been intensely growing as a new drug delivery system. With the use of alternating magnetic fields, it is possible to remotely control the delivery of a drug or any other macromolecule loaded inside the MLs. In this experiment, the release of a fluorescent dye from MLs is achieved through an alternating magnetic field of 20kHz and amplitude below 100A/m, and without a macroscopic temperature increase. Bioelectromagnetics. 35:309-312, 2014. © 2014 Wiley Periodicals, Inc.

The exposure of workers moving in the static magnetic field of magnetic resonance (MR) facilities is investigated through the measurement of the magnetic flux density (perceived as variable in time) by means of a probe integral with the body of the exposed subject. Results of measurements performed in 1.5T, 3T e 7T MR environments are presented and discussed in light of the appropriate regulations.

Gli ultimi anni hanno visto un uso crescente degli apparecchi di risonanza magnetica (RM) nella pratica medica; contemporaneamente è aumentata l’attenzione verso l’esposizione occupazionale dei lavoratori (medici, tecnici di radiologia e infermieri) che operano in prossimità di questi dispositivi, in alcuni casi anche durante la scansione. La recentissima direttiva 2013/35 [1] che ridefinisce (a valle del lungo iter di aggiornamento della precedente direttiva 2004/40 [2]) il quadro normativo per la protezione dei lavoratori dai campi elettromagnetici, deroga in modo condizionato, le attività relative alla RM dalla conformità ai limiti imposti, senza tuttavia sollevare i datori di lavoro dall’obbligo di eseguire una valutazione del rischio, come prescritto anche nel Testo Unico sulla Salute e Sicurezza sul Lavoro [3]. Durante un esame di RM sono presenti tre tipi di segnali elettromagnetici: un campo magnetico statico di alta intensità, un campo magnetico di gradiente (CMG) alle frequenze intermedie e un campo magnetico pulsato a radiofrequenza. In questo lavoro verranno presentati i risultati di due campagne di misura effettuate presso due apparecchi di RM a corpo intero a 1.5 T e a 3 T, svolte al fine di valutare l’esposizione dei lavoratori ai soli CMG. Questo tipo di segnale presenta andamenti temporali piuttosto complessi e, ad oggi, metriche e procedure per una valutazione del rischio adeguata non sono state ancora definite. In questo ambito, si è ritenuto utile analizzare le forme d’onda acquisite applicando il metodo del picco ponderato (MPP) nel dominio del tempo e nel dominio della frequenza, per confrontare i risultati e fornire informazioni utili all’implementazione del metodo stesso. Il MPP per la valutazione di segnali complessi (non sinusoidali) è stato proposto dall’International Commission on Non-Ionizing Radiation Protection (ICNIRP) [4] ed esplicitamente recepito come approccio preferenziale nella Direttiva Europea 2013/35 [1].

An improved microchamber for electrical detection of biological cells was designed, fabricated and tested. The microchamber was formed between a gold coplanar stripline fabricated on a sapphire microscope slide and a single microfluidic channel fabricated in a polydimethylsiloxane cover. Compared with the previous design of a coplanar waveguide on a quartz slide with multiple microfluidic channels, the present microchamber was more sensitive, compact, rugged, and transparent. Tests on Jurkat cells in both time and frequency domains demonstrated single-cell sensing potential, as well as discrimination of live vs. dead cells. The test results could be explained by a simple equivalent-circuit model, which efficiently de-embedded the intrinsic cell properties from solution and electrode effects. © 2013 European Microwave Association.

The wide diffusion of Magnetic Resonance Imaging (MRI) in diagnostics and research, with a trend towards high field systems (3T and 7T), has raised the attention on the possible health and safety risks for MRI workers due to exposure to electromagnetic fields (EMF). Three different EMF sources are present in MRI systems: a strong static magnetic field; a low-frequency gradient magnetic field and a radio-frequency electromagnetic field; furthermore, operators moving in the magnet room experience a very low frequency "perceived" magnetic field, due to the inhomogeneity of the static field. While all MRI workers are exposed to static and perceived magnetic fields, only the staff present during the scan in particular situations (e.g. anesthesiologists in pediatric examinations) is exposed to all sources. This study describes an occupational survey conducted in Italy according to a protocol for exposure assessment that we developed in accordance with the 2010 guidelines of the International Commission on Non-Ionizing Radiation Protection (ICNIRP). In the investigated practices, the most significant contribution to occupational exposure was due to the gradient field which, however, resulted compliant with the ICNIRP reference levels. For what concerns the movements in the static field, which are related to the possible onset of sensory effects such as nausea, dizziness and perception of magnetophosphenes, measured data were processed according to an original method, currently under revision following the new 2014 ICNIRP guidelines. Realistic operator movements have also been filmed and associated with the data. As a future development of this study, new measurement campaigns are being planned, in order to correlate the field levels with the sensory effects possibly experienced by the operators.