After entry into force of the Stockholm Convention and Aarhus Protocol and in order to implement the upcoming European legal background, the European countries are asked to apply control measures to ...reduce the release of persistent organic pollutants (POPs) such as dioxins and furans (PCDD/PCDF) and polychlorinated biphenyls as well as to establish POPs release inventories. In this perspective, development of measuring techniques of emissions is a focal issue in acquiring useful information. In this paper, results of various measurement campaigns at different municipal waste incineration (MWI) plants using long-term automated sampling of PCDD/PCDF are presented. The samples collected from both manual and automated campaigns were analyzed following the European Standard EN-1948:2006 by high-resolution gas chromatograph/high-resolution mass spectrometer. Performances of two different commercial systems have been investigated. Anomalous values occurred during one long-term campaign (22.16 pg I-toxic equivalent (TEQ)/Nm
3
), compared to average values (4–5 pg I-TEQ/Nm
3
) of the MWI. At this maximum value, a main occurrence of abnormal and instable operating conditions has been found. Sampling based on long-term basis was found to be more reliable to monitor PCDD/PCDF emissions than occasional short-term sampling. Nevertheless, the results of long-term campaigns demonstrate that emission levels detected in 15–30 days campaigns, when unsteady operating conditions can occur, as start-up and shut down, are not immediately comparable to the typical levels in a 6–8 h, when operating conditions are generally stable. Moreover, there are often differences observed in the congener profiles between short- and long-term campaigns.
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CEKLJ, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Purpose
PCDD/Fs, PCBs, and PAHs, ubiquitous environmental pollutants which are part of the POPs, are mainly produced by anthropogenic activities as well as by natural processes. Occurrences of these ...pollutants in different sites in Trieste are presented. PCDD/Fs distribution and their possible emission sources are discussed.
Methods
Air samples were collected in different sites near the industrial area, in the city center, and in a background area, using a high-volume sampler equipped with a quartz fiber filter and a PUF. Each sampling lasted a week.
Results
The concentrations of the organochlorinated pollutants are consistent with literature data (ΣPCDD/Fs and Σdl-PCBs were 5–38 fg TEQ/Nm
3
and 4–31 fg TEQ/Nm
3
, respectively), and an apparent seasonal trend was found with slightly higher concentrations in the winter and lower levels in both summer campaigns. Moreover, the isomer profile of each sampling campaign was compared to the fingerprint of a sintering plant, a cement plant, and an incinerator, the main industrial activities in Trieste.
Conclusions
The organic micropollutants were detected in levels consistent with literature data. The results show that the pollutants are uniformally distributed in the atmosphere of Trieste. PCDD/F fingerprints in each site remained almost identical during summer and winter, confirming the yearly prevalence of the emissions from the nearby sintering plant.
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CEKLJ, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Since the publication of the first version of European standard EN-1948 in 1996, long-term sampling equipment has been improved to a high standard for the sampling and analysis of ...polychlorodibenzo-p-dioxin (PCDD)/polychlorodibenzofuran (PCDF) emissions from industrial sources. The current automated PCDD/PCDF sampling systems enable to extend the measurement time from 6–8 h to 15–30 days in order to have data values better representative of the real pollutant emission of the plant in the long period. EN-1948:2006 is still the European technical reference standard for the determination of PCDD/PCDF from stationary source emissions. In this paper, a methodology to estimate the measurement uncertainty of long-term automated sampling is presented. The methodology has been tested on a set of high concentration sampling data resulting from a specific experience; it is proposed with the intent that it is to be applied on further similar studies and generalized. A comparison between short-term sampling data resulting from manual and automated parallel measurements has been considered also in order to verify the feasibility and usefulness of automated systems and to establish correlations between results of the two methods to use a manual method for calibration of automatic long-term one. The uncertainty components of the manual method are analyzed, following the requirements of EN-1948-3:2006, allowing to have a preliminary evaluation of the corresponding uncertainty components of the automated system. Then, a comparison between experimental data coming from parallel sampling campaigns carried out in short- and long-term sampling periods is realized. Long-term sampling is more reliable to monitor PCDD/PCDF emissions than occasional short-term sampling. Automated sampling systems can assure very useful emission data both in short and long sampling periods. Despite this, due to the different application of the long-term sampling systems, the automated results could not be directly compared with manual results, not even in terms of measurement uncertainty. This investigation focuses on both uncertainty and repeatability of the automated sampling method. The standard 20988, developed by Internarional Organization of Standardization (ISO) can be used to estimate the measurement uncertainty. The results confirm that the uncertainties of manual and automated methods are comparable. At the same time, it is not appropriate to consider the manual method as a reference for the evaluation of the uncertainty of the automated sampling system, due to the high variability of both systems.
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CEKLJ, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Abstract
Most published sleep studies use three species: human, house mouse, or Norway rat. The degree to which data from these species captures variability in mammalian sleep remains unclear. To ...gain insight into mammalian sleep diversity, we examined sleep architecture in the spiny basal murid rodent
Acomys cahirinus
. First, we used a piezoelectric system validated for
Mus musculus
to monitor sleep in both species. We also included wild
M. musculus
to control for alterations generated by laboratory-reared conditions for
M. musculus
. Using this comparative framework, we found that
A. cahirinus
, lab
M. musculus,
and wild
M. musculus
were primarily nocturnal, but exhibited distinct behavioral patterns. Although the activity of
A. cahirinus
increased sharply at dark onset, it decreased sharply just two hours later under group and individual housing conditions. To further characterize sleep patterns and sleep-related variables, we set up EEG/EMG and video recordings and found that
A. cahirinus
sleep significantly more than
M. musculus
, exhibit nearly three times more REM, and sleep almost exclusively with their eyes open. The observed differences in
A. cahirinus
sleep architecture raise questions about the evolutionary drivers of sleep behavior
.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
This paper considers a job sequencing problem for a single numerical controlled machining center. It is assumed that all the considered jobs must be processed on a single machine provided with a tool ...magazine with C positions, that no job requires more than C tools to be completely machined and that the tools may be loaded and unloaded from the tool magazine only when the machining operations for each job are completed. The decisional problem is referred to as the tool loading problem (TLP) and it determines the jobs machining sequence as well as the tools to load in the machine tool magazine before the machining operations on each job may start. In industrial cases where the tool switching time is both significant relative to job processing time and proportional to the number of tool switches, the performance criterion is the minimization of the number of tool switches. This paper demonstrates that the TLP is a symmetric sequencing problem. The authors enrich a branch-and-bound algorithm proposed in literature for the TLP with the new symmetric formulation. Computational experiments show the significant improvement obtained by the novel symmetric formulation of the TLP.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The high-frequency performance of transistors is usually assessed by speed and gain figures of merit, such as the maximum oscillation frequency f
, cutoff frequency f
, ratio f
/f
, forward ...transmission coefficient S
, and open-circuit voltage gain A
. All these figures of merit must be as large as possible for transistors to be useful in practical electronics applications. Here we demonstrate high-performance graphene field-effect transistors (GFETs) with a thin AlOx gate dielectric which outperform previous state-of-the-art GFETs: we obtained f
/f
> 3, A
> 30 dB, and S
= 12.5 dB (at 10 MHz and depending on the transistor geometry) from S-parameter measurements. A dc characterization of GFETs in ambient conditions reveals good current saturation and relatively large transconductance ~600 S/m. The realized GFETs offer the prospect of using graphene in a much wider range of electronic applications which require substantial gain.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
This paper addresses a particular stochastic lot-sizing and scheduling problem. The evolution of the uncertain parameters is modelled by means of a scenario tree and the resulting model is a ...multistage stochastic mixed-integer program. We develop a heuristic approach that exploits the specific structure of the problem. The computational experiments carried out on a large set of instances have shown that the approach provides good quality solutions in a reasonable amount of time. PUBLICATION ABSTRACT
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CEKLJ, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Contact resistance is one of the main factors limiting performance of short-channel graphene field-effect transistors (GFETs), preventing their use in low-voltage applications. Here we investigated ...the contact resistance between graphene grown by chemical vapor deposition (CVD) and different metals, and found that etching holes in graphene below the contacts consistently reduced the contact resistance, down to 23 Ω⋅μm with Au contacts. This low contact resistance was obtained at the Dirac point of graphene, in contrast to previous studies where the lowest contact resistance was obtained at the highest carrier density in graphene (here 200 Ω⋅μm was obtained under such conditions). The 'holey' Au contacts were implemented in GFETs which exhibited an average transconductance of 940 S m−1 at a drain bias of only 0.8 V and gate length of 500 nm, which out-perform GFETs with conventional Au contacts.
La nutrition parentérale à domicile (NPAD) est une alternative à l’hospitalisation de longue durée pour les patients insuffisants intestinaux. Cette prise en charge est complexe, obligeant la famille ...à pratiquer des soins techniques sur cathéter central. Les premières semaines au retour de l’hospitalisation sont les plus critiques, en cause : un stress important, la complexité du circuit, la quantité importante d’information et parfois certains contextes sociaux et/ou la barrière de la langue. Des erreurs de rythme d’administration durant cette période sont souvent rapportées avec une surconsommation en poches de secours. Pour aider les familles des patients nouvellement inclus dans la cohorte de NPAD, nous nous sommes intéressés au développement d’un outil permettant l’accompagnement des parents sur l’administration des nutrition parentérale (NP). Celui-ci doit permettre de faciliter la prise en charge autonome au domicile tout en limitant les risques d’erreurs d’administration. Il s’insérera dans le programme d’éducation thérapeutique (ETP) de formation à la NPAD déjà existant.
Une revue des prescriptions des 69 patients de la cohorte NPAD a permis de sélectionner 2 familles de patients. Elles ont été choisies pour leur bonne compréhension du circuit et leur inclusion récente dans la cohorte NPAD. Des entretiens semi-structurés avec ces familles ont permis de mettre en évidence les difficultés rencontrées par les parents au début du traitement.
Ces entretiens ont permis de valider un plan d’administration des poches de NP. Il permet au patient de savoir quand administrer chaque poche grâce à une représentation visuelle sur l’ensemble de la semaine. Il est ainsi facilement compréhensible de tous. Il rappelle pour chaque patient, son circuit de livraison et les points clés à vérifier au moment de celle-ci. Une fois construit, cet outil a été présenté aux 2 familles tests pour être évalué et validé. Il sera diffusé systématiquement à tous patients lors de chaque inclusion dans la cohorte NPAD ou changement de prescription. Il est remis et expliqué par un pharmacien de l’unité de nutrition parentérale au cours d’un entretien déjà présent dans le programme ETP de formation à la NPAD.
Le partenariat patients-soignants a permis la réalisation d’un outil destiné à sécuriser le retour au domicile des patients. Il est centré sur les besoins des patients, il est adaptable à tous et compréhensible même en cas de barrière de la langue. Les premiers retours obtenus sont très positifs et les familles plus rassurées. Une réévaluation de cet outil, avec de nouveaux patients, est prévue à 6 mois puis annuellement.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Benzocaine‐induced methemoglobinemia is a rare but life‐threatening event. The use of topical benzocaine spray in a 77‐year‐old woman during endoscopic retrograde cholangiopancreatogram produced ...marked cyanosis and mrthemoglobin levels consistent with methemoglobinemia. Immediate recognition and prompt treatment of the disorder are essential to decrease morbidity and mortality.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
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