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See detailHigh-temperature and quantitative XRD study of typical Westerwald clays (Germany)
Fontaine, François ULg; Fagel, Nathalie ULg

Poster (2016, July 05)

The Westerwald is one of the largest and oldest clay mining area of Germany. Those deposits were formed during the Eocene and Oligocene as a result of the weathering, erosion and redeposition of Devonian ... [more ▼]

The Westerwald is one of the largest and oldest clay mining area of Germany. Those deposits were formed during the Eocene and Oligocene as a result of the weathering, erosion and redeposition of Devonian rocks. During the Miocene, intense volcanic activities led to a large basalt cover, protecting the clays from the erosion. The fine fraction is mainly composed of kaolinite and illite, with the possible presence of interstratified I S. Other minerals such as quartz, feldspars, hematite, goethite or anatase are present in variable concentrations. Four typical Westerwald clays were chosen for this study: kaolinite-rich clay, kaolinite-illite clay, a red and a yellow firing clays. The first goal is to perform quantitative XRD using two different methods and to compare them: reference intensity ratio (RIR) and Rietveld (using Topas and BGMN). The second goal is the study of those samples using high-temperature XRD (HTXRD). The samples were heated up to 1250°C and a XRD pattern was obtained in situ every 100°C. The results show the temperatures of vitrification and formation of mullite and cristobalite varying from one sample to another, which is mainly linked to their flux concentration. [less ▲]

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See detailBeyond national accounting figures: how quantification practices reshape the state
Piron, Damien ULg

Conference (2016, July 05)

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See detailDémographie et performances zootechniques des élevages bovins traditionnels au Nord Bénin
Chabi Toko, Roukayath ULg; Adégbidi, Anselme; Lebailly, Philippe ULg

in Revue d'Elévage et de Médecine Vétérinaire des Pays Tropicaux (2016), 69(1), 33-39

The study was conducted with 150 Fulani herders in the departments of Borgu and Alibori in Benin. It aimed to determine the zootechnical parameters of traditional cattle farms. The survey collected ... [more ▼]

The study was conducted with 150 Fulani herders in the departments of Borgu and Alibori in Benin. It aimed to determine the zootechnical parameters of traditional cattle farms. The survey collected information on the characteristics of cattle herds. The results showed a high proportion of females (76%), an average herd size (66 animals) and the prevalence of the Borgu breed (86%). The herds also showed a low breeding performance, characterized by a high calf mortality rate (10%), and low reproductive parameters (64% calving and fertility rates). In a year, 0.57 calf was weaned on average by its dam. The low performance of cattle farms in coastal countries such as Benin is consistent with that of pastoral areas, which is complementary in terms of meat supply to West African markets. [less ▲]

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See detailChangement des formes de l'éthos de l'enseignant sous l’influence des médias
Vintila, Elena-Georgiana ULg

Scientific conference (2016, July 04)

Seit langem, wenn man über Gruppen spricht, versucht man sie mit einem bestimmenden Merkmal, mit einem Bild, zu verbinden. Demnach, wurde das Bild des Professors mit dem Bild des Gelehrten verbunden, wie ... [more ▼]

Seit langem, wenn man über Gruppen spricht, versucht man sie mit einem bestimmenden Merkmal, mit einem Bild, zu verbinden. Demnach, wurde das Bild des Professors mit dem Bild des Gelehrten verbunden, wie Gustave Flaubert (Dictionnaire d’idées reçues, 1913) „Professeur : Toujours savant» ou « Grammairiens : Tous pédants ” getan hat. Aber die Professoren, für die jeden Tag eine öffentliche Rede, ein Schüller-Publikum bedeutet, enthüllen während der Rede ein Selbstbild, das durch und dank dieser Rede geschaffen wird. Dieses Bild kann beginnend mit den Spuren interpretiert werden, die es hinterlässt, kurz gesagt, anhand der Beobachtung des Ethos. Ein von Patrick Charaudeau verwendeten Begriff, das Ethos ist an dem Sprechakt verbunden, wie von Dominique Maingueneau (2002 : en ligne) unterstrichen „l’ethos se montre dans l’acte d’énonciation, il ne se dit pas dans l’énonce ”. Das Bild des Professors, der in einem Unterrichtsraum Unterricht erteilen kann, enthält Besonderheiten, die aus der Rolle und Position resultieren, die er hat, aus dem „Bild”, das er selbst auf dem Internet vorschlägt, das Selbstbild. Dieses Bild ist das Ergebnis der Weise in der er wählt, wie er das Blog und die pädagogischen Strategien baut, die er benutzt. Die Zusammenhänge zwischen den Aspekten der Sprache (in der Sprache des Blogs erkennbar) und die soziallen Aspekte (bemerkbar gleichzeitig mit der Stellung als Professor) sind aber viel mehr komplex und problematisch. Durch die Analyse einiger Professor-Blogs möchten wir beobachten, wie die Professoren durch digitale Netzwerke „ersichtbar werden”, wie die Wahrnehmung des Berufs als Professor verändert hat und was für Veränderungen des vordiskursiven Ethos der Gruppe „der Professoren” aufgetreten haben. [less ▲]

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See detailAzacytidine mitigates experimental sclerodermic graft-versus-host disease
Fransolet, Gilles ULg; Ehx, Grégory ULg; SOMJA, Joan ULg et al

in Journal of Hematology & Oncology (2016)

Background Previous studies have demonstrated that regulatory T cells (Tregs) play a protective role in the pathogenesis of chronic graft-versus-host disease (cGVHD). Tregs constitutively express the gene ... [more ▼]

Background Previous studies have demonstrated that regulatory T cells (Tregs) play a protective role in the pathogenesis of chronic graft-versus-host disease (cGVHD). Tregs constitutively express the gene of the transcription factor Foxp3 whose CNS2 region is heavily methylated in conventional CD4+ T cells (CD4+Tconvs) but demethylated in Tregs. Methods Here, we assessed the impact of azacytidine (AZA) on cGVHD in a well-established murine model of sclerodermic cGVHD (B10.D2 (H-2d) → BALB/cJ (H-2d)). Results The administration of AZA every 48 h from day +10 to day +30 at the dose of 0.5 mg/kg or 2 mg/kg mitigated chronic GVHD. Further, AZA-treated mice exhibited higher blood and thymic Treg frequencies on day +35, as well as higher demethylation levels of the Foxp3 enhancer and the IL-2 promoter in splenocytes at day +52. Interestingly, Tregs from AZA-treated mice expressed more frequently the activation marker CD103 on day +52. AZA-treated mice had also lower counts of CD4+Tconvs and CD8+ T cells from day +21 to day +35 after transplantation, as well as a lower proportion of CD4+Tconvs expressing the Ki67 antigen on day +21 demonstrating an anti-proliferating effect of the drug on T cells. Conclusions Our results indicate that AZA prevented sclerodermic cGVHD in a well-established murine model of cGVHD. These data might serve as the basis for a pilot study of AZA administration for cGVHD prevention in patients at high risk for cGVHD. [less ▲]

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See detailCONTRIBUTION A L’ETUDE DE L’ECHOGRAPHIE INTERVENTIONNELLE DU RACHIS CHEZ LE CHIEN : MISE AU POINT DE TECHNIQUES ECHOGUIDEES POUR LES PONCTIONS SOUS-ARACHNOÏDIENNES ET ANALYSE DE LEUR APPLICATION
Etienne, Anne-Laure ULg

Doctoral thesis (2016)

SUMMARY Percutaneous ultrasound guidance has become a routine procedure in veterinary medicine in domestic animals. It allows precise placement of the needle in the desired target. Punctures of the ... [more ▼]

SUMMARY Percutaneous ultrasound guidance has become a routine procedure in veterinary medicine in domestic animals. It allows precise placement of the needle in the desired target. Punctures of the subarachnoid space in dogs are frequently carried out in veterinary practice for diagnostic purposes. In these procedures, the placement of the needle into the subarachnoid space (atlanto-occipital or lumbar) is commonly performed blindly by feeling the bony anatomical landmarks but this can be laborious or even impossible in some patients as reported in human medicine. The topic of this study is ultrasound guidance for the placement of the needle during puncture of the subarachnoid space. The needle placement can be done under ultrasound guidance according to two methods. The "indirect guidance" is a method of deferred ultrasound guidance. The "direct guidance" is a real time procedure in which the operator holds the needle in one hand and the ultrasound probe in the other. It allows direct visualization of the needle (if direct guidance), the target structure, adjacent tissues (including vascular structures) and potential injectate while minimizing the risk of complications. Punctures of the subarachnoid space are carried out by placing the needle in the cisterna magna or in the caudal lumbar subarachnoid space (between the fifth and sixth lumbar vertebrae). The cisternal puncture is most frequently used in practice but presents greater risk of iatrogenic lesions of the brain stem. The lumbar puncture is technically more difficult and is frequently contaminated by iatrogenic blood. Cerebrospinal fluid punctures have several clinical applications. They allow to collect cerebrospinal fluid for diagnostic testing, to realize myelograms or myeloscanners by injecting contrast medium and to perform spinal anesthesia or analgesia by injecting one or more substance(s) blocking the conduction of the spinal nerves. Subarachnoid lumbar puncture is used commonly in the dog for cerebrospinal fluid collection and/or myelography. Percutaneous ultrasound anatomy of the lumbar region in the dog and a technique for ultrasound-guided lumbar puncture were described in the first study. Ultrasound images obtained ex- vivo and in-vivo were compared with anatomic sections and used to identify the landmarks for ultrasound-guided lumbar puncture. The ultrasound-guided procedure was established on cadavers and then applied in-vivo on eight dogs. The anatomic landmarks for the ultrasound-guided puncture, which should be identified using the parasagittal oblique ultrasound image, were the articular processes of the fifth and sixth lumbar vertebrae and the interarcuate space. The spinal needle was directed under direct ultrasound-guidance toward the triangular space located between the contiguous articular processes of the fifth and sixth lumbar vertebrae and then advanced to enter the vertebral canal. Using these precise ultrasound anatomic landmarks, an ultrasound-guided technique for lumbar puncture is applicable to dogs. Cisternal puncture in dogs and cats is commonly carried out. Percutaneous ultrasound anatomy of the cisternal region in the dog and the cat and an indirect technique for ultrasound-guided cisternal puncture were described in the second study. Ultrasound images obtained ex-vivo and in-vivo were compared with anatomic sections and used to identify the landmarks for ultrasound-guided cisternal puncture. The ultrasound-guided procedure was established in cadavers and then applied in- vivo in seven dogs and two cats. The anatomic landmarks for the ultrasound-guided puncture were the cisterna magna, the spinal cord, the two occipital condyles on transverse images, the external occipital crest and the dorsal arch of the first cervical vertebra on longitudinal images. Using these ultrasound anatomic landmarks, an indirect ultrasound-guided technique for cisternal puncture is applicable to dogs and cats. The standard technique for placing a needle into the canine lumbar subarachnoid space is primarily based on the palpation of anatomic landmarks and the use of probing movements of the needle. However, this technique can be challenging for novice operators. The aim of the third observational, prospective, ex vivo, feasibility study was to compare ultrasound-guided versus standard anatomic landmark approaches for novices performing needle placement into the lumbar subarachnoid space using dog cadavers. Eight experienced operators validated the canine cadaver model as usable for training landmark and ultrasound-guided needle placement into the lumbar subarachnoid space based on realistic anatomy and tissue consistency. With informed consent, 67 final year veterinary students were prospectively enrolled in the study. Students had no prior experience in needle placement into the lumbar subarachnoid space nor use of ultrasound. Each student received a short theoretical training about each technique before the trial and then attempted blind landmark-guided and ultrasound-guided techniques on randomized canine cadavers. After having performed both procedures, the operators completed a self-evaluation questionnaire about their performance and self-confidence. Total success rates for students were 48% and 77% for the landmark- and ultrasound-guided technique, respectively. Ultrasound guidance significantly increased total success rate when compared to the landmark-guided technique and significantly reduced the number of attempts. With ultrasound guidance self-confidence was improved, without bringing any significant change in duration of the needle placement procedure. Findings indicated that the use of ultrasound guidance and cadavers is a feasible method for training novice operators in needle placement into the canine lumbar subarachnoid space after short theoretical training. Ultrasound-guided techniques for needle placement in the cisterna magna and in the lumbar subarachnoid space were described in the dog. The aim of the fourth observational, prospective, ex-vivo study was to compare the impact of ultrasound guidance for the cisternal versus lumbar needle placement using dog cadavers. With informed consent, 83 operators were prospectively enrolled in the study. They were divided in four groups depending on experience. Each operator received a short theoretical training about each technique before the trial and then attempted a cisternal and lumbar punctures with blind landmark-guided and ultrasound-guided techniques on randomized canine cadavers. The lumbar ultrasound-guidance was direct while the cisternal ultrasound-guidance was indirect. After having performed each procedure, the operators completed a self-evaluation questionnaire about their previous experience, their performance and their self-confidence. The ultrasound guidance significantly increased total success rate in both areas compared with the blind technique but more significantly in the lumbar region. The cisternal ultrasound guidance significantly improved the number of attempts, the time needed to perform the procedure and the self-confidence in inexperienced and experienced operators. The lumbar ultrasound guidance significantly increased the self-confidence in inexperienced and experienced operators and significantly decreased the number of attempts in inexperienced operators. The first cause of failure cited was different according to the location of the puncture and was related to the nature of ultrasound guidance. Findings indicated that the use of ultrasound guidance by novice and experienced operators improved different parameters according to the location of the needle placement. This study demonstrated that inexperienced operators are able to use ultrasound guidance after a short theoretical teaching session in an ex-vivo context and this supports the use of ultrasound-guidance for learning and teaching purposes. The study of the impact of ultrasound guidance for needle placement procedures described in this work could be developed and studied for other technically difficult or risky procedures on dogs. If the benefits of ultrasound guidance demonstrated ex-vivo in this work are transferable to the clinical conditions, punctures of the subarachnoid injections would be less « scary » for novice operators and become routine procedures applicable by a large numbers of veterinarians. [less ▲]

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See detailHow elites talk about their political career: Metaphors in spontaneous and informal political discourse
Heyvaert, Pauline ULg

Conference (2016, July 02)

It has often been acknowledged that political discourse is a genre that naturally allows for metaphor use. Moreover, recent research has demonstrated the importance of analysing the political impact of ... [more ▼]

It has often been acknowledged that political discourse is a genre that naturally allows for metaphor use. Moreover, recent research has demonstrated the importance of analysing the political impact of these metaphors: “Examining metaphors that appear in political discourse provides insights into the way speakers understand their situation, and how they seek to accomplish their ends” (Ritchie, 2013). Previous research (Perrez&Reuchamps, 2014) has demonstrated the usefulness of applying Steen’s three-dimensional model of metaphor analysis in communication to a corpus of political discourse. I therefore propose to apply this model to a particular type of elite discourse. The corpus used for this research consists of biographical interviews conducted with Walloon politicians, each describing at length their personal political career within the political dynamics of their country. This corpus offers an interesting ground of investigation because of its spontaneous and informal character. Moreover, most studies on the use of metaphors in political discourse tend to focus on elite discourse with the underlying assumption that elites might knowingly use metaphors to convince the audience. What is interesting with our corpus, is that the interviews do not have a clear addressee or audience. Analysing the form, and particularly the metaphor use of these interviews comes with a number of questions: (i) do politicians use metaphors in spontaneous discourse; (ii) if so, when and (iii) why do they use these metaphors, i.e. do they use them with a specific purpose, as for example explaining a complex political issue, or not? To assess the extent to which politicians use metaphors in spontaneous discourse, we conducted a corpus analysis by applying the MIPVU procedure (Steen et al., 2010) in order to identify potential metaphorical contexts. In line with Steen’s three-dimensional model, we subsequently analysed the identified metaphors by making a distinction between three different layers of metaphor, respectively at the linguistic, conceptual and communicative level. [less ▲]

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See detailAsymptotic properties of free monoid morphisms
Charlier, Emilie ULg; Leroy, Julien ULg; Rigo, Michel ULg

in Linear Algebra & its Applications (2016), 500

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See detailCOST Action FA1407: Empowering NGS technologie for study and diagnostic of plant viruses
Massart, Sébastien ULg; Petter, François

Conference (2016, July)

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See detailA comprehensive system of control characters for Ancient Egyptian hieroglyphic text in Unicode
Nederhof, Mark-Jan; Rajan, Vinodh; Lang, Johannes et al

Computer development (2016)

We propose a comprehensive system of control characters for encoding Ancient Egyptian hieroglyphs in Unicode.

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See detailSoyons optimistes
RADERMECKER, Régis ULg

in Revue de l'Association Belge du Diabète (2016), 59(4), 3

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See detailLes mustères de la "Viege noire" ou comment se passe la demande d'allocation de handicap
Marquet, Françoise; RADERMECKER, Régis ULg

in Revue de l'Association Belge du Diabète (2016), 59(4), 9-13

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See detailOn (Eventually) Monotone Dynamical Systems and Positive Koopman Semigroups
Sootla, Aivar ULg; Mauroy, Alexandre ULg

Conference (2016, July)

Monotone systems are dynamical systems whose solutions preserve a partial order in initial conditions for all times. It stands to reason that some systems may preserve a partial order only after an ... [more ▼]

Monotone systems are dynamical systems whose solutions preserve a partial order in initial conditions for all times. It stands to reason that some systems may preserve a partial order only after an initial transient. These systems are usually called eventually monotone. While monotone systems have an easy characterization in terms of the sign pattern of the Jacobian matrix (i.e. Kamke-M\"uller condition), eventually monotone systems have not been characterized in such an explicit manner. In order to provide such a characterization, we drew inspiration from the results for linear systems, where eventually monotone (positive) systems are studied using the spectral properties of the system (i.e. Perron-Frobenius property). In the case of nonlinear systems, a spectral characterization of nonlinear eventually monotone systems is not straightforward, but can be obtained in the framework of the so-called Koopman operator. Additionally, we explore connections between (eventual) monotonicity and (eventual) positivity of the Koopman semigroup. This allows to view our results as a generalization of the Perron-Frobenius theory to nonlinear dynamical systems. We consider a biologically inspired example to illustrate the applicability of eventual monotonicity. [less ▲]

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See detailDisrupted interaction between self and memory in patients with Alzheimer’s disease
Genon, Sarah ULg; Salmon, Eric ULg; Collette, Fabienne ULg et al

Conference (2016, July)

In humans, self and memory processes interact as evidenced by the self reference (SRE) and self reference recollection effects (SRRE). However, in patients with Alzheimer’s disease (AD), this relationship ... [more ▼]

In humans, self and memory processes interact as evidenced by the self reference (SRE) and self reference recollection effects (SRRE). However, in patients with Alzheimer’s disease (AD), this relationship can be disrupted. This was evidenced by impaired SRE and SRRE in AD for recognition of adjectives previously judged for self-relevance, as well as recall of names of people previously linked to the self. For both materials, a qualitative impairment of the recollective experience for the self-related items was also observed in AD. A neuroimaging approach suggested that reduced SRE is related to decreased grey matter volume in the lateral prefrontal cortex (lPFC). Thus, retrieval of recent self-related memories is impaired in relation to altered high-order processes in lPFC in AD. [less ▲]

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See detailModelling Type 1 Diabetes Mellitus Blood Glucose Dynamics as a Monotone System
Sootla, Aivar ULg; Cescon, Marzia

Conference (2016, July)

In this presentation, we study an FDA-approved Type 1 diabetes mellitus (T1DM) blood glucose dynamics simulator used in the majority of the practical studies on Artificial Pancreas (AP). We show that ... [more ▼]

In this presentation, we study an FDA-approved Type 1 diabetes mellitus (T1DM) blood glucose dynamics simulator used in the majority of the practical studies on Artificial Pancreas (AP). We show that under some physiologically plausible assumptions, the glucoregulatory system described by the model is monotone. This means that the system generates trajectories which are monotone with respect to specific changes in initial conditions and control signals. This strong property leads to many interesting observations. By using monotonicity, for example, it becomes straightforward to compute bounds on glucose concentration subject to variations in intake of carbohydrates and insulin injections. Monotonicity also rigorously justifies recent studies on fundamental limitations in glucose control. [less ▲]

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See detailHeritage Conservation in River Corridor Cities. The Case of Tripoli, Lebanon.
Ginzarly, Manal ULg; Teller, Jacques ULg

Conference (2016, July)

This article recognizes rivers as cultural heritage landscapes, as an integral component of cities common heritage and an element of collective memory and identity. It is based on the consideration that ... [more ▼]

This article recognizes rivers as cultural heritage landscapes, as an integral component of cities common heritage and an element of collective memory and identity. It is based on the consideration that analysis of the socio-spatial relationship between the river and urban structure at different historical period can further lead to knowledge about the river contribution in forming the identity and sense of place of an urban area. This knowledge can be used to inform urban conservation as well as development practices to support the integral spatial and cultural relation between the city and the river in order to maintain the character of river city. This article takes the historic core in the city of Tripoli, Lebanon as a case study where conservation practices have followed a monument centric approach focusing on the restoration of heritage buildings and sites and neglecting the cultural value of the Abu Ali River flowing through the city. It conducts a multi- dimensional morphological analysis that is based on archival review and field work to extract the social value of the river and its contribution to the urban morphology of the city. [less ▲]

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See detailSPARC Report on the Mystery of Carbon Tetrachloride
Ahmadzai, H; Bock, R P; Burkholder, J B et al

in Liang, Qing; Newman, Paul A; Reimann, Stefan (Eds.) SPARC Report on the Mystery of Carbon Tetrachloride (2016)

The Montreal Protocol (MP) controls the production and consumption of carbon tetrachloride (CCl4 or CTC) and other ozone-depleting substances (ODSs) for emissive uses. CCl4 is a major ODS, accounting for ... [more ▼]

The Montreal Protocol (MP) controls the production and consumption of carbon tetrachloride (CCl4 or CTC) and other ozone-depleting substances (ODSs) for emissive uses. CCl4 is a major ODS, accounting for about 12% of the globally averaged inorganic chlorine and bromine in the stratosphere, compared to 14% for CFC-12 in 2012. In spite of the MP controls, there are large ongoing emissions of CCl4 into the atmosphere. Estimates of emissions from various techniques ought to yield similar numbers. However, the recent WMO/UNEP Scientific Assessment of Ozone Depletion [WMO, 2014] estimated a 2007-2012 CCl4 bottom-up emission of 1-4 Gg/year (1-4 kilotonnes/year), based on country-by-country reports to UNEP, and a global top-down emissions estimate of 57 Gg/ year, based on atmospheric measurements. This 54 Gg/year difference has not been explained. In order to assess the current knowledge on global CCl4 sources and sinks, stakeholders from industrial, governmental, and the scientific communities came together at the “Solving the Mystery of Carbon Tetrachloride” workshop, which was held from 4-6 October 2015 at Empa in Dübendorf, Switzerland. During this workshop, several new findings were brought forward by the participants on CCl4 emissions and related science. • Anthropogenic production and consumption for feedstock and process agent uses (e.g., as approved solvents) are reported to UNEP under the MP. Based on these numbers, global bottom-up emissions of 3 (0-8) Gg/year are estimated for 2007-2013 in this report. This number is also reasonably consistent with this report’s new industry-based bottom-up estimate for fugitive emissions of 2 Gg/year. • By-product emissions from chloromethanes and perchloroethylene plants are newly proposed in this report as significant CCl4 sources, with global emissions estimated from these plants to be 13 Gg/year in 2014. • This report updates the anthropogenic CCl4 emissions estimation as a maximum of ~25 Gg/year. This number is derived by combining the above fugitive and by-product emissions (2 Gg/year and 13 Gg/year, respectively) with 10 Gg/year from legacy emissions plus potential unreported inadvertent emissions from other sources. • Ongoing atmospheric CCl4 measurements within global networks have been exploited for assessing regional emissions. In addition to existing emissions estimates from China and Australia, the workshop prompted research on emissions in the U.S. and Europe. The sum of these four regional emissions is estimated as 21±7.5a Gg/year, but this is not a complete global accounting. These regional top-down emissions estimates also show that most of the CCl4 emissions originate from chemical industrial regions, and are not linked to major population centres. • The total CCl4 lifetime is critical for calculating top-down global emissions. CCl4 is destroyed in the stratosphere, oceans, and soils, complicating the total lifetime estimate. The atmospheric lifetime with respect to stratospheric loss was recently revised to 44 (36-58) years, and remains unchanged in this report. New findings from additional measurement campaigns and reanalysis of physical parameters lead to changes in the ocean lifetime from 94 years to 210 (157-313) years, and in the soil lifetime from 195 years to 375 (288-536) years. • These revised lifetimes lead to an increase of the total lifetime from 26 years in WMO [2014] to 33 (28-41) years. Consequently, CCl4 is lost at a slower rate from the atmosphere. With this new total lifetime, the global top-down emissions calculation decreases from 57 (40-74) Gg/year in WMO [2014] to 40 (25-55) Gg/year. This estimate is relatively consistent with the independent gradient top-down emissions of 30 (25-35) Gg/year, based upon differences between atmospheric measurements of CCl4 in the Northern and Southern Hemispheres. In addition, this new total lifetime implies an upper limit of 3-4 Gg/year of natural emissions, based upon newly reported observations of old air in firn snow. These new CCl4 emissions estimates from the workshop make considerable progress toward closing the emissions discrepancy. The new industrial bottom-up emissions estimate (15 Gg/year total) includes emissions from chloromethanes plants (13 Gg/year) and feedstock fugitive emissions (2 Gg/year). When combined with legacy emissions and unreported inadvertent emissions, this could be up to 25 Gg/year. Top-down emissions estimates are: global 40 (25-55) Gg/year, gradient 30 (25-35) Gg/year, and regional 21 (14-28) Gg/year. While the new bottom-up value is still less than the aggregated top-down values, these estimates reconcile the CCl4 budget discrepancy when considered at the edges of their uncertainties. [less ▲]

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