Pixel characterization for the MFT upgrade of the ALICE experiment

The first collisions from the run II of the Large Hadron Collider (LHC) have started with a p-p energy of 13TeV. By the end of this second run, the initial physics goals of the ALICE experiment will be reached. The foreseen high-luminosity upgrade of the LHC in 2020 will enhance the Pb-Pb collision rate up to 50kHz. In order to fully exploit this future potential, the ALICE collaboration is preparing for a major detector upgrade in 2018. The experiment focuses on the study of strongly interacting matter in extreme conditions of energy and density and in particular the quark gluon plasma (QGP), a new state of matter in which quarks and gluons are no longer bound like in hadrons but can roam freely. The strategy of the collaboration is to extend its physics program for fundamental studies of QCD. This requires high statistics and high precision measurements and will contribute to discriminate between theoretical models. Rare probes play an important part in the physics program and the study of their coupling with the medium and hadronization processes is a major direction in the QGP understanding. The existing Muon spectrometer has produced very interesting results on the production rates of quarkonia and heavy flavor in p-p, Pb-Pb and p-Pb collisions and the second run is expected to deliver even more data. However multiple scattering in its frontal absorber originates a bad spatial resolution on vertices. This results in a high background level in both single muon and dimuon analyses coming from semi-muonic decays of light hadrons and also in limited possibilities to disentangle open charm and open beauty contribution to muon production. To overcome this limitation and to better exploit the unique kinematic range accessible at the LHC by the Muon Spectrometer, the Muon Forward Tracker (MFT) is proposed in the context of the ALICE upgrade plans. Made of 912 pixel silicon sensors in 5 discs surrounding the beampipe, the detector is designed to measure tracks between the interaction point and the frontal absorber in order to be matched with the tracks of the muon spectrometer with an expected resolution lower than 100m. It is foreseen to share the same sensor technology designed for the upgrade of the Inner Tracking System (ITS): ALPIDE which is based on a new silicon pixel technology. This internship focuses on the sensor characterization to optimize the settings in respect to detection efficiency, noise and spatial resolution from the beam test analyse of the latest prototypes.Les premières collisions proton-proton à l’énergie de 13 TeV ont eu lieu avec le début du run II au Large Hadron Collider (LHC). A la fin de cette seconde prise de données, l’expérience ALICE aura atteint les objectifs initiaux du programme de physique qu’elle s’était fixés. Avec l’augmentation de la luminosity du LHC en 2020, le taux d’interactions des collisions Pb-Pb sera augmenté à 50kHz. Afin de tirer parti de ce futur potentiel, la collaboration ALICE se prépare pour une importante mise à jour de son détecteur en 2018. Cette expérience porte sur l’étude des propriétés physiques de la matière soumise à l’interaction forte, dans des conditions d’énergie et de densité extrêmes. Un nouvel état de la matière se forme alors, le plasma de quarks et de gluons (PQG), dans lequel les quarks et les gluons ne sont plus confinés au sein des hadrons mais peuvent évoluer librement. La stratégie de la collaboration est d’étendre son programme de physique pour des études fondamentales de chromodynamique quantique. Cela nécessite à la fois beaucoup de statistiques et des mesures très précises. Les résultats contribueront à affiner les modèles théoriques. Les sondes rares jouent un rôle majeur dans l’étude du PQG. L’observation de leur interaction avec le milieu ainsi que les processus d’hadronisation qui y ont lieu sont des points clés dans sa compréhension. Le spectromètre à muons actuellement présent au sein du détecteur a fourni des résultats très intéressants sur les taux de production de quarkonia et de saveurs lourdes dans les collisions p-p, Pb-Pb et p-Pb. On peut s’attendre à ce que la deuxième période d’exploitation fournisse encore plus de données. Cependant, les diffusions multiples qui ont lieu dans l’absorbeur frontal induisent une mauvaise résolution sur les vertex. Cela se traduit par un bruit de fond élevé dans les canaux muon simple et dimuon, provenant principalement de désintégrations semimuoniques des hadrons légers. Les possibilités d’isoler les contributions du charme et de la beauté ouverts du spectre muonique sont également limitées. Afin de surmonter ces limitations et d’exploiter au maximum l’intervalle cinématique du spectromètre à muons, le Muon Forward Tracker (MFT) est proposé dans le contexte de la mise à jour d’ALICE. Constitué de 912 capteurs à pixels en silicium répartis sur 5 disques autour du faisceau, il est conçu pour détecter les particules entre le point d’interaction et l’absorbeur frontal. Les traces obtenues seront associées avec celles du spectromètre à muons. et la résolution attendue est inférieure à 100 m. Il est prévu de s’aligner sur la même technologie que le futur Inner Tracking System (ITS) avec les capteurs ALPIDE. Ce stage porte sur la caractérisation de ces futurs capteurs et l’optimisation de leurs réglages par rapport à l’efficacité de détection, le niveau de bruit et la résolution spatiale au travers des tests sous faisceaux des derniers prototypes

Commercial extinction: The exhaustion of exhaustion

This contribution addresses the technosocial assemblages that constitute commercial extinction that are not included within the common definition. That is, that a species’ population is so depleted that is no longer profitable to harvest. Extinct for the purposes of commerce

Let them eat cake!

Let them eat cake!' is a food-led event serving an edible imaginary of a Facebook profile. In early 2012, Facebook conducted massive scale emotional contagion by manipulating the emotional expressions in the News Feeds of 689,003 users. This exemplifies how the governability and the biopolitics of everyday life flow through the many layers of shared images, liked videos, protocols, and hyperlinks, all orchestrated by the Facebook News Feed algorithm. 'Let them eat cake!' proposes a gustatory experience to the visitor, a cake imagined with synthetic DNA encoded from a user's Facebook profile data. The profile's data categories (Ad Topics, Facial Recognition Data, Friends, Followers, Likes, and Political Views) are transposed into cake layers, with an absurd twist that reflects the algorithms agency. Ultimately the work explores innovative forms of engagement with complex socio-technical assemblages

Disparities in disruptions to public drinking water services in Texas communities during Winter Storm Uri 2021

Winter Storm Uri of February 2021 left millions of United States residents without access to reliable, clean domestic water during the COVID19 pandemic. In the state of Texas, over 17 million people served by public drinking water systems were placed under boil water advisories for periods ranging from one day to more than one month. We performed a geospatial analysis that combined public boil water advisory data for Texas with demographic information from the 2010 United States Census to understand the affected public water systems and the populations they served. We also issued a cross-sectional survey to account for people’s lived experiences. Geospatial analysis shows that the duration of boil water advisories depended partly on the size of the public water system. Large, urban public water systems issued advisories of intermediate length (5–7 days) and served racially diverse communities of moderate income. Small, mostly rural public water systems issued some of the longest advisories (20 days or more). Many of these systems served disproportionately White communities of lower income, but some served predominantly non-White, Hispanic, and Latino communities. In survey data, “first-generation” participants (whose parents were not college-educated) were more likely to be placed under boil water advisories, pointing to disparate impacts by socioeconomic group. The survey also revealed large communication gaps between public water utilities and individuals: more than half of all respondents were unsure or confused about whether they were issued a boil water advisory. Our study reinforces the need to improve resilience in public water services for large, diverse, urban communities and small, rural communities in the United States and to provide a clear and efficient channel for emergency communications between public water service utilities and the communities they serve. This article includes Accessible Data.Peer ReviewedPostprint (published version

Shrimping under working conditions

We propose that mutated forms of death are emerging with neoliberalism’s biopolitical financialisation of life. Thinking of such forms as commercial extinction and social death, how do we begin to frame these outside of a quantified rhetoric of surplus? These questions aim to provoke a discussion about these terms that can be interpreted as modes of exhaustion, while maintaining particular biological, social or economic conditions of life. When we are confronted with capitalism’s failure to fulfil resource exhaustion, a model of conservation by dispossession1 might emerge within what Rosi Braidotti calls “new and subtler degrees of death and extinction” (2013, 115). In this text we want to think with other conditions of death and extinction that can help to move beyond the missing item of an inventory, a carved rock along a fossil road or a set of pre-emptive actions to be executed beyond a certain threshold. Thus, we ask if there could be figures, which rather than narrating death as a biological or geological concept, open it up to other equally violent forces that are nevertheless materially situated. More importantly, will we ever be able to think of extinction beyond ideas of absence or frame death from social or economic realms as an emerging mode of living? In order to address many of these questions we dissect a critical example of extinction, that of the brown shrimp (Crangon crangon) as it flips between commercial (albeit not yet biotic) death in the ex-fishing grounds of the South East corner of the UK, and the social death embedded in the labour-power of the ex-processing factories of the Special Economic Zones of Tangier and Tetuan in Morocco

RhoB regulates cell migration through altered focal adhesion dynamics

The Rho GTPase RhoB has been shown to affect cell migration, but how it does this is not clear. Here we show that cells depleted of RhoB by RNAi are rounded and have defects in Rac-mediated spreading and lamellipodium extension, although they have active membrane ruffling around the periphery. Depletion of the exchange factor GEF-H1 induces a similar phenotype. RhoB-depleted cells migrate faster, but less persistently in a chemotactic gradient, and frequently round up during migration. RhoB-depleted cells have similar numbers of focal adhesions to control cells during spreading and migration, but show more diffuse and patchy contact with the substratum. They have lower levels of surface β1 integrin, and β1 integrin activity is reduced in actin-rich protrusions. We propose that RhoB contributes to directional cell migration by regulating β1 integrin surface levels and activity, thereby stabilizing lamellipodial protrusions

Fish communities of two tidal creeks in the Pinheiros bay, state of Paraná, southern Brazil

Tidal creeks are meandering channels that are highly influenced by tidal changes and can experience substantial variation in salinity and depth over the course of the same day. The goal of the present work is to survey the ichthyofauna associated with these environments and to assess seasonal differences in their composition in tidal creeks of the euhaline sector of the estuary of the Paranaguá. Two tidal creeks of the Pinheiros bay were sampled monthly at the same time using fyke nets. A total of 13,755 fish from 55 species and 27 families were captured. Only the clupeiforms Anchoa parva, Cetengraulis edentulus, and Harengula clupeola showed substantial seasonal variation in abundance, being most frequent during the fall and its adjacent months. Benthophagic individuals such as Sphoeroides testudineus, Bairdiella ronchus and Cathorops spixii were the most dominant in terms of biomass and were present all year long, although with irregular abundance. Sciaenid species were most frequent in the fall and winter, both as juveniles and as adults. The spring and part of the fall were characterized by the highest number of species with mature gonads, whereas the fall was the most important recruitment period, causing an increase in the richness indices and in the number of captured individuals. Tidal creeks were intensively visited by fish of all trophic levels and ages. These results, together with the high richness and diversity indices, corroborate the importance of tidal creeks for the preservation of estuarine environments.Tidal creeks are meandering channels that are highly influenced by tidal changes and can experience substantial variation in salinity and depth over the course of the same day. The goal of the present work is to survey the ichthyofauna associated with these environments and to assess seasonal differences in their composition in tidal creeks of the euhaline sector of the estuary of the Paranaguá. Two tidal creeks of the Pinheiros bay were sampled monthly at the same time using fyke nets. A total of 13,755 fish from 55 species and 27 families were captured. Only the clupeiforms Anchoa parva, Cetengraulis edentulus, and Harengula clupeola showed substantial seasonal variation in abundance, being most frequent during the fall and its adjacent months. Benthophagic individuals such as Sphoeroides testudineus, Bairdiella ronchus and Cathorops spixii were the most dominant in terms of biomass and were present all year long, although with irregular abundance. Sciaenid species were most frequent in the fall and winter, both as juveniles and as adults. The spring and part of the fall were characterized by the highest number of species with mature gonads, whereas the fall was the most important recruitment period, causing an increase in the richness indices and in the number of captured individuals. Tidal creeks were intensively visited by fish of all trophic levels and ages. These results, together with the high richness and diversity indices, corroborate the importance of tidal creeks for the preservation of estuarine environments

The fecal microbiome in dogs with acute diarrhea and idiopathic inflammatory bowel disease.

Recent molecular studies have revealed a highly complex bacterial assembly in the canine intestinal tract. There is mounting evidence that microbes play an important role in the pathogenesis of acute and chronic enteropathies of dogs, including idiopathic inflammatory bowel disease (IBD). The aim of this study was to characterize the bacterial microbiota in dogs with various gastrointestinal disorders. Fecal samples from healthy dogs (n = 32), dogs with acute non-hemorrhagic diarrhea (NHD; n = 12), dogs with acute hemorrhagic diarrhea (AHD; n = 13), and dogs with active (n = 9) and therapeutically controlled idiopathic IBD (n = 10) were analyzed by 454-pyrosequencing of the 16S rRNA gene and qPCR assays. Dogs with acute diarrhea, especially those with AHD, had the most profound alterations in their microbiome, as significant separations were observed on PCoA plots of unweighted Unifrac distances. Dogs with AHD had significant decreases in Blautia, Ruminococcaceae including Faecalibacterium, and Turicibacter spp., and significant increases in genus Sutterella and Clostridium perfringens when compared to healthy dogs. No significant separation on PCoA plots was observed for the dogs with IBD. Faecalibacterium spp. and Fusobacteria were, however, decreased in the dogs with clinically active IBD, but increased during time periods of clinically insignificant IBD, as defined by a clinical IBD activity index (CIBDAI). Results of this study revealed a bacterial dysbiosis in fecal samples of dogs with various GI disorders. The observed changes in the microbiome differed between acute and chronic disease states. The bacterial groups that were commonly decreased during diarrhea are considered to be important short-chain fatty acid producers and may be important for canine intestinal health. Future studies should correlate these observed phylogenetic differences with functional changes in the intestinal microbiome of dogs with defined disease phenotypes

Structural brain injury in patients with disorders of consciousness: A voxel-based morphometry study.

MAIN OBJECTIVE: Disorders of consciousness (DOC; encompassing coma, vegetative state/unresponsive wakefulness syndrome (VS/UWS) and minimally conscious state minus/plus (MCS-/+)) are associated with structural brain injury. The extent of this damage remains poorly understood and merits a detailed examination using novel analysis techniques. Research design/methods and procedures: This study used voxel-based morphometry (VBM) on structural magnetic resonance imaging scans of 61 patients with DOC to examine grey and white matter injury associated with DOC, time spent in DOC, aetiology and diagnosis. MAIN OUTCOMES AND RESULTS: DOC and time spent in DOC were found to be associated with widespread structural brain injury, although the latter did not correlate strongly with injury in the right cerebral hemisphere. Traumatic, as compared to non-traumatic aetiology, was related to more injury in the brainstem, midbrain, thalamus, hypothalamus, basal forebrain, cerebellum, and posterior corpus callosum. Potential structural differences were found between VS/UWS and MCS and between MCS- and MCS+, but need further examination. CONCLUSIONS: The findings indicate that both traumatic and non-traumatic DOC are associated with widespread structural brain injury, although differences exist that could lead to aetiology-specific treatment strategies. Furthermore, the high degree of atrophy occurring after initial brain injury prompts the development and use of neuroprotective techniques to potentially increase patients\u27 chances of recovery