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Wildfires are increasing in importance in many regions of the Canadian boreal forest and are an ongoing risk for forest management activities. We simulated the effects of fires on long-term harvest levels on the 59 forest management units of the province of Québec, Canada, for the 2020–2100 period. Different climate change pathways (stable, RCP 4.5 or 8.5) and salvage logging rates (20% or 70% of mature burned stands) were simulated. Changes in forest flammability due to climate change, species migration, and forest management were also considered. Under stable climatic conditions, the decline in potential harvest levels due to fire, based on 50 simulations per scenario, ranged between 3% and 33% (mean = 11%) when high salvage logging rates were simulated, compared to 6%–45% (mean = 20%) for low salvage rates. Climate change caused increases in burn rates between −3% and 39% for RCP 4.5 and between 33% and 69% for RCP 8.5 at the end of the 21st century, depending on fire zones. However, the effects of these modified burn rates on harvest levels did not differ substantially from those of baseline burn rates, probably because the projected burn rates were highest during the later part of the simulations (2070–2100), when their impacts on harvest level calculations were limited. This study indicates that potential harvest levels calculated without considering wildfires are likely to be non-sustainable.

Postfire salvage logging is used to reduce economic losses; however, burned trees are rapidly colonized by wood-boring insects, which reduce the merchantable value of the wood. This study aims to predict wood borer (Monochamus Megerle in Dejean, 1821) attacks after wildfire as a function of rapidly available variables such as tree basal area, stem diameter, and burn severity using the differenced normalized burn ratio (dNBR). In 2011, we sampled 60 black spruce (Picea mariana (Mill.) Britton, Sterns & Poggenb.) or jack pine (Pinus banksiana Lamb.) plots in five burns from 2010 in the Haute-Mauricie region of Quebec, Canada. A 50 cm bole section was debarked on seven trees in each plot to estimate wood borer attack density. Wood borer attacks were more abundant in black spruce than in jack pine. As a continuous variable, dNBR unveiled a quadratic effect of burn severity on attack density in black spruce, which was higher at moderate burn severity. In jack pine, the highest levels of attack density were found at high burn severity. Models produced in this article will help forest managers to better prioritize areas for salvage logging and thus reduce economic losses due to wood borer activity.

Managers designing infrastructure in fire-prone wildland areas require assessments of wildfire threat to quantify uncertainty due to future vegetation and climatic conditions. In this study, we combine wildfire simulation and forest landscape composition modeling to identify areas that would be highly susceptible to wildfire around a proposed conservation corridor in Québec, Canada. In this measure, managers have proposed raising the conductors of a new 735-kV hydroelectric powerline above the forest canopy within a wildlife connectivity corridor to mitigate the impacts to threatened boreal woodland caribou (Rangifer tarandus). Retention of coniferous vegetation, however, can increase the likelihood of an intense wildfire damaging powerline infrastructure. To assess the likelihood of high-intensity wildfires for the next 100 years, we evaluated three time periods (2020, 2070, 2120), three climate scenarios (observed, RCP 4.5, RCP 8.5), and four vegetation projections (static, no harvest, extensive harvesting, harvesting excluded in protected areas). Under present-day conditions, we found a lower probability of high-intensity wildfire within the corridor than in other parts of the study area, due to the protective influence of a nearby, poorly regenerated burned area. Wildfire probability will increase into the future, with strong, weather-induced inflation in the number of annual ignitions and wildfire spread potential. However, a conversion to less-flammable vegetation triggered by interactions between climate change and disturbance may attenuate this trend. By addressing the range of uncertainty of future conditions, we present a robust strategy to assist in decision-making about long-term risk management for both the proposed conservation measure and the powerline.

How the genetic landscape of a tumor governs the tumor’s response to immunotherapy remains largely elusive. Here, we established a direct in vivo CRISPR/Cas9 gene editing methodology to assess the immune-modulatory capabilities of 573 putative cancer genes associated with altered cytotoxic activity in human cancers. Using KrasG12D- and BrafV600E-driven mouse lung cancer models, we identify Serpinb9 and Adam2 as our top immune suppressive and immune enhancing genes, respectively. Mechanistically, we show that Serpinb9 ablation in KrasG12D- and BrafV600E-mutant lung tumor cells greatly enhances the efficacy of cytotoxic T-cells in vitro and in vivo. ADAM2 is a cancer testis antigen broadly expressed in human cancers such as lung adenocarcinoma (13.9%), renal (74.7%), prostate (72.4%), uterine (28.6%) and invasive breast (9.5%) cancer. In our mouse models, we show that Adam2 expression is induced in KrasG12D- but not BrafV600E-driven murine lung tumors and that its expression is further enhanced by immunotherapy. We show that loss of Adam2 significantly decreases KrasG12D-lung tumor burden but blocks the efficacy of cytotoxic T-cells. Consistently, Adam2 overexpression dramatically increases tumor growth and enhances immunotherapy efficacy. Mechanistically, we find that Adam2’s oncogenic function depends on modulating the tumor immune microenvironment by restraining productive type I and type II interferon responses as well as cytokine signaling, reducing the presentation of tumor-associated antigen, and modulating surface expression of several immunoregulatory receptors within Kras-driven lung tumors. Adam2 expression also leads to reduced levels of immune checkpoint inhibitors such as Pd-l1, Lag3, Tigit and Tim3. This reduced exhaustion within the tumor microenvironment may explain why ex vivo expanded and adoptively transferred cytotoxic T-cells show enhanced cytotoxic efficacy against Adam2 overexpressing lung tumors. Together, our study highlights the power of integrating cancer genomic with in vivo CRISPR/Cas9 screens to uncover how cancer-associated genetic alterations control responses to immunotherapies.

In the managed forest of Canada, forest fires are actively suppressed through efficient initial attack capability; however, the impact of different factors on the suppression success remains to be understood. The aim of this paper was to analyze the influence of operational suppression objectives (fire detection, initial attack, and fire control) along with fire intensity, fuel type, fire ignition cause, year, workload, and homogeneous fire regime zones on the achievement of the fire suppression objective (fire < 3 ha) using the Forest Fire Protection Agency of Quebec (SOPFEU) as a case study. The overall success of the suppression objective was very high (88%) over the study period (1994–2015). Both detection and control had significant effects on the suppression success through their interaction with fuel type, ignition cause, fire intensity, and zone variables. When the suppression objective was not achieved, final fire size was influenced by control, fuel type, fire intensity, and zone. The paper highlights the importance of the operational objectives and of regional differences for both fire suppression success and final fire size. Our results can help forest fire protection agencies to better understand their wildland fire suppression systems for a better adaptation to the upcoming fire regime changes. We gratefully acknowledge the Société de protection des forêts contre le feu (SOPFEU) and Mélanie Desrochers for providing the databases for the study. We thank Yan Boulanger and Steve Cumming for their constructive comments on an earlier version of this paper. The authors are thankful to Isabelle Lamarre for improving the quality of the English text. Research funding was provided by the New Forests European project to A. Cardil and by a postdoctoral research scholarship from the FRQNT (Fonds de recherche du Québec – Nature et technologies) to M. Lorente.

The transcription factor (TF) GRHL2 controls normal epithelial differentiation in different tissues. It is expressed in all breast cancer subtypes except those with a mesenchymal phenotype (claudin-low subtype), where its ectopic expression leads to induction of a mesenchymal-epithelial transition (MET) (1). Here we explored the mechanisms by which GRHL2 induces MET in claudin-low breast cancer cell lines using a combination of ChIP-seq and RNAseq analyses upon modulation of GRHL2 expression in mesenchymal and epithelial cell lines. Direct DNA binding by GRHL2 was enriched in proximity of genes positively regulated in mesenchymal cell lines, which include several epithelial TFs as well as an array of epithelial genes. Biotinylation and mass spectrometry analysis of membrane proteins confirmed surfaceome remodeling via induction of membrane proteins with roles in cell-cell contacts and adhesion. Repression of mesenchymal genes was mediated in part by direct induction of miRNAs targeting mesenchymal transcription factors. In addition, GRHL2 strongly induced expression of the cofactor VGLL1, whose expression is high in the triple-negative (TNBC) basal-like subtype. VGLL1 overexpression in mesenchymal cell lines and suppression in basal-like TNBC cells confirmed its role in mediating part of GRHL2 signaling, in particular via interaction with and modulation of TEAD transcription factors. In addition, GRHL2 also interacted with VGLL1 upon its induction in mesenchymal cells, recruiting it to some of its binding motifs, suggesting a multilayered cross-talk between GRHL2 and TEAD factors. Together, our results indicate that GRHL2 acts as a master regulator in the induction of TNBC epithelial differentiation via direct upregulation of epithelial transcription factors, miRNAs and TEAD cofactor VGLL1, resulting in both upregulation of epithelial genes and suppression of mesenchymal genes.(1) Cieply B. et al., Cancer Res. 2013 Oct. 1;73 (20): 6299-309 Presentation: Tuesday, June 14, 2022 10:15 a.m. - 10:30 a.m.

Lung cancer causes more deaths annually than any other malignancy. A subset of non-small cell lung cancer (NSCLC) is driven by amplification and overexpression or activating mutation of the receptor tyrosine kinase (RTK) ERBB2. In some contexts, notably breast cancer, alternative splicing of ERBB2 causes skipping of exon 16, leading to the expression of an oncogenic ERBB2 isoform (ERBB2ΔEx16) that forms constitutively active homodimers. However, the broader implications of ERBB2 alternative splicing in human cancers have not been explored. Here, we have used genomic and transcriptomic analysis to identify elevated ERBB2ΔEx16 expression in a subset of NSCLC cases, as well as splicing site mutations facilitating exon 16 skipping and deletions of exon 16 in a subset of these lung tumors and in a number of other carcinomas. Supporting the potential of ERBB2ΔEx16 as a lung cancer driver, its expression transformed immortalized lung epithelial cells while a transgenic model featuring inducible ERBB2ΔEx16 specifically in the lung epithelium rapidly developed lung adenocarcinomas following transgene induction. Collectively, these observations indicate that ERBB2ΔEx16 is a lung cancer oncogene with potential clinical importance for a proportion of patients.

International audience; Over the past 50years, increasing experimental evidences have established that connexins (Cxs) and gap junctional intercellular communication (GJIC) ensure an important role in both the onset and development of cancerous processes. In the present review, we focus on the impact of Cxs and GJIC during the development of prostate cancer (PCa), from the primary growth mainly localized in acinar glands and ducts to the distant metastasis mainly concentrated in bone. As observed in several other types of solid tumours, Cxs and especially Cx43 exhibit an ambivalent role with a tumour suppressor effect in the early stages and, conversely, a rather pro-tumoural profile for most of invasion and dissemination steps to secondary sites. We report here the current knowledge on the function of Cxs during PCa cells migration, cytoskeletal dynamics, proteinases activities and the cross talk with the surrounding stromal cells in the microenvironment of the tumour and the bones. In addition, we discuss the role of Cxs in the bone tropism even if the prostate model is rarely used to study the complete sequence of cancer dissemination compared to breast cancer or melanoma. Even if not yet fully understood, these recent findings on Cxs provide new insights into their molecular mechanisms associated with progression and bone targeted behaviour of PCa. This article is part of a Special Issue entitled: Gap Junction Proteins edited by Jean Claude Herve.

Simple Summary In its late stages, prostate cancer (PCa) is characterized by a high propensity to form osteoblastic bone metastases, mainly treated by palliative approaches. In a previous work, we demonstrated that a gap junctional protein, connexin43 (Cx43) is implicated both in the increase of aggressiveness of PCa cells and in their impact on bone. To analyze the reciprocal part of the dialogue, the current study addresses the role of Cx43 in the impact of bone microenvironment on PCa cells abilities. Using Cx43-overexpressing PCa cell lines, we determined that Cx43 is necessary for promigratory effect induced by osteoblastic conditioned media (ObCM) on individual cells. Next, we demonstrated the requirement of Cx43 membrane localization at the leading edge and the involvement of the cytoplasmic part in this ObCM-induced migration. Overall, our findings precise the role of Cx43 during PCa progression and its putative use as aggressiveness marker and as potential therapeutic targets. Abstract Among the different interacting molecules implicated in bone metastases, connexin43 (Cx43) may increase sensitivity of prostate cancer (PCa) cells to bone microenvironment, as suggested by our in silico and human tissue samples analyses that revealed increased level of Cx43 expression with PCa progression and a Cx43 specific expression in bone secondary sites. The goal of the present study was to understand how Cx43 influences PCa cells sensitivity and aggressiveness to bone microenvironment. By means of Cx43-overexpressing PCa cell lines, we revealed a Cx43-dependent promigratory effect of osteoblastic conditioned media (ObCM). This effect on directional migration relied on the presence of Cx43 at the plasma membrane and not on gap junctional intercellular communication and hemichannel functions. ObCM stimulation induced Rac1 activation and Cx43 interaction with cortactin in protrusions of migrating PCa cells. Finally, by transfecting two different truncated forms of Cx43 in LNCaP cells, we determined that the carboxy terminal (CT) part of Cx43 is crucial for the responsiveness of PCa cells to ObCM. Our study demonstrates that Cx43 level and its membrane localization modulate the phenotypic response of PCa cells to osteoblastic microenvironment and that its CT domain plays a pivotal role.

Satellite-derived spectral indices such as the relativized burn ratio (RBR) allow fire severity maps to be produced in a relatively straightforward manner across multiple fires and broad spatial extents. These indices often have strong relationships with field-based measurements of fire severity, thereby justifying their widespread use in management and science. However, satellite-derived spectral indices have been criticized because their non-standardized units render them difficult to interpret relative to on-the-ground fire effects. In this study, we built a Random Forest model describing a field-based measure of fire severity, the composite burn index (CBI), as a function of multiple spectral indices, a variable representing spatial variability in climate, and latitude. CBI data primarily representing forested vegetation from 263 fires (8075 plots) across the United States and Canada were used to build the model. Overall, the model performed well, with a cross-validated R2 of 0.72, though there was spatial variability in model performance. The model we produced allows for the direct mapping of CBI, which is more interpretable compared to spectral indices. Moreover, because the model and all spectral explanatory variables were produced in Google Earth Engine, predicting and mapping of CBI can realistically be undertaken on hundreds to thousands of fires. We provide all necessary code to execute the model and produce maps of CBI in Earth Engine. This study and its products will be extremely useful to managers and scientists in North America who wish to map fire effects over large landscapes or regions.

Fire-killed timber is considered as a loss of potential revenues and is thus increasingly salvaged, though not without concerns for biodiversity conservation. Indeed, a large diversity of burn-associated saproxylic beetles use recently burned trees. This study intends to reduce potential impacts of salvage logging on biodiversity by identifying high conservation value forests (HCVFs) for burn-associated beetles, which are considered the most at risk. In five burns ignited naturally in 2010 in the eastern Canadian boreal forest, we selected 31 and 29 stands of black spruce and jack pine respectively. Three 50-cm bole segments were retrieved from each stand and placed in emergence cages to measure tree utilisation by saproxylic beetles. This yielded 7235 beetles from 103 taxa, of which 67 were considered rare ( 5% occurrence in logs). Among the common taxa, we identified six groups of ecologically related species using co-occurrence-based hierarchical clustering, among which three were mainly formed by opportunistic species that are currently of little concern in a post-fire logging context. The three other groups were formed by burn-associated species that could be affected by salvage logging. HCVFs include jack pine stands and large trees of either tree species of low- to mid-range burn severity. We also recommend retaining the periphery of burned stands, as ecotones are rich habitats used by several burn-associated species that are found in low numbers in green forests but they benefit from burned habitats by increasing their populations significantly.

The molecular mechanisms governing the formation of lymphatic vasculature are not yet well understood. Pannexins are transmembrane proteins that form channels which allow for diffusion of ions and small molecules (

This article is a report of the "International Colloquium on Gap junctions: 50 Years of Impact on Cancer" that was held 8-9 September 2016, at the Amphitheater "Pole Biologie Sante" of the University of Poitiers (Poitiers, France). The colloquium was organized by M Mesnil (Universite de Poitiers, Poitiers, France) and C Naus (University of British Columbia, Vancouver, Canada) to celebrate the 50th anniversary of the seminal work published in 1966 by Loewenstein and Kanno [Intercellular communication and the control of tissue growth: lack of communication between cancer cells, Nature, 116 (1966) 1248-1249] which initiated studies on the involvement of gap junctions in carcinogenesis. During the colloquium, 15 participants presented reviews or research updates in the field which are summarized below.

IF 5.008; International audience; Extensive invasion and angiogenesis are hallmark features of malignant glioblastomas. Here, we co-cultured U87 human glioblastoma cells and human microvascular endothelial cells (HMEC) to demonstrate the exchange of microRNAs that initially involve the formation of gap junction communications between the two cell types. The functional inhibition of gap junctions by carbenoxolone blocks the transfer of the anti-tumor miR-145-5p from HMEC to U87, and the transfer of the pro-invasive miR-5096 from U87 to HMEC. These two microRNAs exert opposite effects on angiogenesis in vitro. MiR-5096 was observed to promote HMEC tubulogenesis, initially by increasing Cx43 expression and the formation of heterocellular gap junctions, and secondarily through a gap-junction independent pathway. Our results highlight the importance of microRNA exchanges between tumor and endothelial cells that in part involves the formation of functional gap junctions between the two cell types.

Early postfire habitats harbour numerous saproxylic species. Some are opportunistic feeders, while others are closely associated with burned forests. This distinction is important for developing sound postfire forest management aimed at conserving biodiversity, as concerns should be mostly directed towards burn-associated saproxylic beetles rather than opportunistic species. Here, we examine species-habitat associations, temporal dynamics, and community structure of saproxylic beetles in black spruce and jack pine stands disturbed by wildfire and by a “non-fire” disturbance generated by girdling trees to mimic the small-scale gap dynamics characterizing old-growth boreal forests in Canada. We used flightinterception traps and reared logs to compare abundance, species richness, and species composition of saproxylic beetles among treatments. We found that over 30% of saproxylic beetles had an affinity with jack pine or black spruce affected by either fire or girdling. Assemblages consistently diff...

Fire-generated mosaics of habitat legacies such as dead and dying trees are key structural components in boreal forest ecosystems that support diverse saproxylic beetles. Our study sought to elucidate the spatial pattern of community composition (beta diversity) of saproxylic beetles along gradients of post-fire habitat legacies (tree species composition, tree size [dbh], and burn severities) and geographical distance. For 2 y, we reared saproxylic beetles from 360 logs retrieved from 72 sites in burned forests. Tests were performed to explain the overall beta diversity (βsor) by partitioning it into its 2 components: the “species spatial turnover” due to species replacement (βsim) and the “richness-driven” beta diversity due to species richness differences (βrich)- Variations in tree species, tree size, and burn severity had significant effects on overall beta diversity (βsor) of saproxylic beetles; these effects varied according to the differential influence of these factors on the 2 distinct ...

There is considerable variation in the degree of burn severity in boreal fires. One approach that has been used to capture this variation from field and remote sensing perspectives for western Canadian boreal forests is the Composite Burn Index (CBI) and differenced Normalized Burn Ratio (dNBR). Of interest was how well these methods may perform for fires in eastern Canada. This study investigated the CBI-dNBR relationship for selected fires in the eastern boreal forests of Canada, with a view towards contributing to the generalisation of a Canada-wide model. Results for the sampled region showed no difference in the CBI-dNBR relationship between black spruce- and jack pine-dominated stands, whereas this relationship was best described by a Generalised Additive Model (GAM). The dNBR-derived maps would also be useful in support of research and post-fire management in burns outside the studied territory and time frame covered by the existing burn severity mapping system already used in this region. The Saturated growth model proposed for the western boreal region also performed well for our eastern boreal region, thus further supporting the development of a national model.

Biodiversity patterns vary across space and time, and this variation is thought to be driven by several ecological/biogeographical processes that act upon species distributions and leave their imprint at various spatial and temporal scales (Huston, 1994; Ricklefs, 2004). The regional or geographical (gamma diversity) diversity patterns, in addition to local diversity (alpha diversity), are consequent upon the extent of “spatial” variation in species composition among sites (beta diversity) (Whittaker, 1960; 1972). Arrays of ecological hypotheses have been proposed as determinants of beta diversity patterns. It can arise from variation in environmental/habitat heterogeneity among sites, spatial constraints, disturbance regimes, and corresponding species-level variations in life history traits (e.g., dispersal, niche-breadth) (Harrison et al., 1992; Nekola & White, 1999; Chase, 2007; Veech & Crist, 2007; Baselga, 2008) as well as neutral and/or stochastic processes (Hubbell, 2001; Chase, 2010). Nevertheless, beta diversity patterns and the mechanisms by which ensembles of local communities maintain their variations and, consequently, influence diversity at regional scale remains a central challenge in ecological and conservation studies (Wilson & Shmida, 1984; Veech & Crist, 2007; Baselga, 2010; Chase, 2010; Tuomisto, 2010; Anderson et al., 2011). Despite its apparent conceptual simplicity, the empirical assessment of beta diversity has been mired with extensive debates over a perplexing array of indices, analytical approaches, or scales of analysis (Wilson & Shmida, 1984; Lande, 1996; Loreau, 2000; Koleff et al., 2003; Tuomisto & Ruokolainen, 2006; Legendre et al., 2008; Veech & Crist, 2010; for a detailed outline of the issues, see recent review by Anderson et al., 2011). One of the most fundamental and recurrent challenges in beta diversity studies has been distinguishing and quantifying the pure “spatial” turnover component of beta diversity from that caused by variation in species richness between local communities (Wilson & Shmida, 1984; Koleff et al., 2003; Veech & Crist

II y a desormais plusieurs evidences quant au fait que la coupe de recuperation nuirait au retablissement des processus ecologiques naturels, telle la regeneration d'especes vegetales. En effet, si certaines especes saproxyliques boreales sont adaptees aux habitats brules avec lesquels elles ont evolue, la coupe de recuperation pourrait exceder leur resilience. Ainsi, cette etude a comme but d'identifier les especes associees aux brulis et de determiner l'effet reel de la reduction en surface terriere commerciale, dans le temps suivant la coupe de recuperation apres feu, sur les assemblages de coleopteres associes aux brulis de la foret boreale de la province de Quebec au Canada. La coupe de recuperation a ete effectuee d'aout 2005 a mai 2006 suite aux feux de foret de 2005 ayant eu lieu dans la region de Chibougamau. Nous avons echantillonne les coleopteres au cours des trois premieres annees suivant la coupe de recuperation (2006 - 2008) a l'aide de pieges a impact multidirectionnels. Dix pieges furent installes dans dix sites egalement repartis entre des peuplements non-brules domines soit par Tepinette noire (Picea mariana Mill. B.S.P.) ou le pin gris (Pinus banksiana Lamb.), ou 11 arbres avaient ete anneles afin de generer des chicots recents. Trente-six autres pieges ont ete installes dans 36 sites brules repartis entre des peuplements residuels a la coupe de recuperation d'epinette noire ou de pin gris, de facon a couvrir le plus large eventail de niveau de recuperation. Pour chacun des sites brules, nous avons mesure des attributs de l'habitat, affectes par la recuperation et pouvant affecter la structure des assemblages associes aux brulis, dont : la surface terriere des tiges residuelles par essence et par classe de diametre a diverses echelles (0.04 ha et 7 ha). Nous avons aussi mesure la distance entre les sites et la foret non-brulee continue et la severite du feu en utilisant le « delta Normalized Burn Ratio (dNBR)». En etudiant les assemblages de coleopteres des familles retenues (Buprestidae, Cerambycidae, Cleridae, Corylophidae, Curculionidae, Elateridae, Lathridiidae et Salpingidae) des sites brules et des sites non- brules contenant des arbres anneles, nous avons identifie 18 especes associees aux brulis. Ces coleopteres associes aux brulis n'ont repondu a la coupe de recuperation qu'a Tannee no.2 (2007) apres l'intervention. Les assemblages de coleopteres associes aux brulis ont ete principalement faconnes par trois groupes de facteurs environnementaux : 1) les conditions de la foret avant feu, tel la composition en essences; 2) les conditions generees par le feu, soit la distance a la foret non-brulee, directement influencee par la forme du brulis, et la severite du feu; 3) la quantite d'aire recuperee et la reduction associee en chicots de coniferes matures (dhp > 9 cm).

The present paper studies the boron (B) diffusion in nitrogen (N) doped amorphous silicon (a-Si) layer in original bi-layer B-doped polycrystalline silicon (poly-Si)/in-situ N-doped Si layers (NIDOS) thin films deposited by low pressure chemical vapor deposition (LPCVD) technique. The B diffusion in the NIDOS layer was investigated by secondary ion mass spectrometry (SIMS) and Fourier transform infrared spectroscopy (FTIR) analysis. A new extended diffusion model is proposed to fit the SIMS profile of the bi-layer films. This model introduces new terms which take into account the effect of N concentration on the complex diffusion phenomena of B atoms in bi-layer films. SIMS results show that B diffusion does not exceed one third of NIDOS layer thickness after annealing. The reduction of the B diffusion in the NIDOS layer is due to the formation of complex B–N as shown by infrared absorption measurements. Electrical measurements using four-probe and Hall effect techniques show the good conductivity of the B-doped poly-Si layer after annealing treatment.

International audience; Hole mobility degradation has been studied in high-dose boron-implanted ultrashallow junctions containing high concentrations of boron-interstitial clusters BICs, combining an empirical method based on the self-consistent interpretation of secondary-ion-mass spectrometry SIMS and Hall measurements and liquid-nitrogen LN 2 to room temperature RT hole mobility measurements. It has been found that BICs act as independent scattering centers which have a strong impact on hole mobility in addition to the other scattering mechanisms such as lattice and impurities scattering. A mobility degradation coefficient has been introduced, which gives information on the mobility degradation level in the analyzed junctions. In the case of very high concentrations of BICs containing a boron density up to 8 10 14 cm −2 , measured hole mobilities were found to be 40% lower than corresponding theoretical values. BICs dissolution through multiple Flash anneals at high temperature 1300 ° C reduces the observe mobility degradation.