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See detailLow-Density Structures in the Local Universe. II. Nearby Cosmic Voids
Elyiv, Andrii ULg; Karachentsev, I.D.; Karachentseva, V.E. et al

in Astrophysical Bulletin (2013), 68

We present the results of the search for spherical volumes containing no galaxies with luminosities brighter than the Magellanic Clouds in the Local Supercluster and its vicinity. Within a distance of 40 ... [more ▼]

We present the results of the search for spherical volumes containing no galaxies with luminosities brighter than the Magellanic Clouds in the Local Supercluster and its vicinity. Within a distance of 40 Mpc from us, 89 cosmic voids were discovered with the diameters of 24 to 12 Mpc, containing no galaxies with absolute magnitudes brighter than M_K < -18.4. A list of these voids and the sky distribution maps are given. It was found that 93% of spherical voids overlap, forming three more extended percolated voids (hypervoids). The largest of them, HV1, has 56 initial spherical cells and extends in a horseshoe shape, enveloping the Local Volume and the Virgo cluster. The Local Void (Tully, 1988) in the Hercules-Aquila region is the closest part of the HV1. Another hypervoid, HV2, contains 22 spherical voids in the Eridanus constellation, and the third compact hypervoid (HV3) comprises 6 spherical cells in the Bootes. The total volume of these voids incorporates about 30% of the Local Universe. Among 2906 dwarf galaxies excluded from the original sample (n = 10502) in the search for spherical volumes, only 68 are located in the voids we have discovered. They are characterized by late morphological types (85% are Ir, Im, BCD, Sm), absolute magnitudes M_B ranging from -13.0 to -16.7, moderate star formation rates (log SSFR ~ -10 M_sun/(yr*L_sun) and gas reserves per luminosity unit twice to three times larger than in the other dwarf galaxies located in normal environments. The dwarf population of the voids shows a certain tendency to sit shallow near the surfaces of cosmic voids. [less ▲]

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See detailLow-Dimensional Transport and Large Thermoelectric Power Factors in Bulk Semiconductors by Band Engineering of Highly Directional Electronic States
Bilc, Daniel ULg; Hautier, Geoffroy; Waroquiers, David et al

in Physical Review Letters (2015), 114

Thermoelectrics are promising for addressing energy issues but their exploitation is still hampered by low efficiencies. So far, much improvement has been achieved by reducing the thermal conductivity but ... [more ▼]

Thermoelectrics are promising for addressing energy issues but their exploitation is still hampered by low efficiencies. So far, much improvement has been achieved by reducing the thermal conductivity but less by maximizing the power factor. The latter imposes apparently conflicting requirements on the band structure: a narrow energy distribution and a low effective mass. Quantum confinement in nanostructures andtheintroductionofresonantstatesweresuggestedaspossiblesolutionstothisparadox,butwithlimited success. Here, we propose an original approach to fulfill both requirements in bulk semiconductors. It exploits the highly directional character of some orbitals to engineer the band structure and produce a type of low-dimensional transport similar to that targeted in nanostructures, while retaining isotropic properties. Using first-principle calculations, the theoretical concept is demonstrated in Fe2YZ Heusler compounds, yielding power factors 4 to 5 times larger than in classical thermoelectrics at room temperature. Our findings are totally generic and rationalize the search of alternative compounds with similar behavior. Beyond thermoelectricity, these might be relevant also in the context of electronic, superconducting, or photovoltaic applications. [less ▲]

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See detailLow-dose methotrexate: an effective corticosteroid-sparing agent in the musculoskeletal manifestations of sarcoidosis
Kaye, O.; Palazzo, E.; Grossin, M. et al

in British Journal of Rheumatology (1995), 34(7), 642-644

Extrapulmonary sarcoidosis, and particularly the presence of musculoskeletal complications of the disease, may require chronic corticosteroid therapy. In five patients with biopsy-proven sarcoidosis and ... [more ▼]

Extrapulmonary sarcoidosis, and particularly the presence of musculoskeletal complications of the disease, may require chronic corticosteroid therapy. In five patients with biopsy-proven sarcoidosis and presenting recalcitrant forms of the disease, we introduced low-dose oral methotrexate (MTX) [10 mg/week (7.5-15)] for 30 months (16-34) to control the clinical and biological symptoms as well as to try to reduce the intolerated steroid posology. Beneficial effects were observed within 8-12 weeks in all patients, which allowed a reduction of 59% (35-75) of the corticosteroid posology, and maintained with a follow-up of 3 yr in 4/5 patients. No significant toxicity was observed. MTX appears to be an efficient, safe and corticosteroid-sparing therapeutic agent for the treatment of recalcitrant musculoskeletal manifestations of sarcoidosis. [less ▲]

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See detailLow-energy social housings Marchin (BE): A case study revisited
Desmecht, James; Dupagne, Albert ULg; Hauglustaine, Jean-Marie ULg et al

in Maldonado, Eduardo; Yannas, Simos (Eds.) Environmentally Friendly Cities (1998, June)

In, 1997, the LEMA research team revisited 20 house settlement of Marchin. It was to assess the houses performances 15 years after their construction, and check the possible interactions between "energy ... [more ▼]

In, 1997, the LEMA research team revisited 20 house settlement of Marchin. It was to assess the houses performances 15 years after their construction, and check the possible interactions between "energy-conscious design" and social factors. This paper briefly exposes the results of this recent reassessment, in the light of the project requirements, design options and design methodology. It indicates that careful design may guarantee, for quite long periods of time, both robustness and affordability of "energy-conscious" housings. [less ▲]

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See detailLow-field magnetoresistance in La0.7Ca0.3MnO3 manganite compounds prepared by the spray drying technique
Vertruyen, Bénédicte ULg; Rulmont, André ULg; Cloots, Rudi ULg et al

in Journal of Materials Science (2005), 40(1), 117-122

Calcium-substituted lanthanum manganite compounds were synthesized by the spray drying technique. This method - whose main advantages are versatility, high reproducibility and scalability - yields small ... [more ▼]

Calcium-substituted lanthanum manganite compounds were synthesized by the spray drying technique. This method - whose main advantages are versatility, high reproducibility and scalability - yields small grain materials of high homogeneity and displaying low-field magnetoresistance effects. We report about the physical and chemical characterizations of these samples in order to investigate the potential interest of spray drying for the production of materials for low-field magnetoresistance applications. We have studied the dependence of the low-field magnetoresistance on the temperature and duration of the thermal treatment applied to the pelletized powders. The issue of the shape anisotropy (demagnetisation effects) influence on the magnetoresistance properties has also been dealt with. (C) 2005 Springer Science + Business Media, Inc. [less ▲]

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See detailLow-flow aortic stenosis and preserved left ventricular ejection fraction
LANCELLOTTI, Patrizio ULg; KOU, Seisyou

in Journal of Echocardiography (2014), 12(1), 12-16

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See detailLow-Flow, Low-Gradient Severe Aortic Stenosis Despite Normal Ejection Fraction Is Associated With Severe Left Ventricular Dysfunction as Assessed by Speckle-Tracking Echocardiography: A Multicenter Study.
Adda, J.; Mielot, C.; Giorgi, R. et al

in Circulation: cardiovascular imaging (2012)

Background- Low-flow low-gradient (LFLG) is sometimes observed in severe aortic stenosis (AS) despite normal ejection fraction, but its frequency and mechanisms are still debated. We aimed to describe the ... [more ▼]

Background- Low-flow low-gradient (LFLG) is sometimes observed in severe aortic stenosis (AS) despite normal ejection fraction, but its frequency and mechanisms are still debated. We aimed to describe the characteristics of patients with LFLG AS and assess the presence of longitudinal left ventricular dysfunction in these patients. Methods and Results- In a multicenter prospective study, 340 consecutive patients with severe AS and normal ejection fraction were studied. Longitudinal left ventricular function was assessed by 2D-strain and global afterload by valvulo-arterial impedance. Patients were classified according to flow and gradient: low flow was defined as a stroke volume index ≤35 mL/m(2), low gradient as a mean gradient ≤40 mm Hg. Most patients (n=258, 75.9%) presented with high-gradient AS, and 82 patients (24.1%) with low-gradient AS. Among the latter, 52 (15.3%) presented with normal flow and low gradient and 30 (8.8%) with LFLG. As compared with normal flow and low gradient, patients with LFLG had more severe AS (aortic valve area=0.7±0.12 cm(2) versus 0.86±0.14 cm(2)), higher valvulo-arterial impedance (5.5±1.1 versus 4±0.8 mm Hg/mL/m(2)), and worse longitudinal left ventricular function (basal longitudinal strain=-11.6±3.4 versus -14.8±3%; P<0.001 for all). Conclusions- LFLG AS is observed in 9% of patients with severe AS and normal ejection fraction and is associated with high global afterload and reduced longitudinal systolic function. Patients with normal-flow low-gradient AS are more frequent and present with less severe AS, normal afterload, and less severe longitudinal dysfunction. Severe left ventricular longitudinal dysfunction is a new explanation to the concept of LFLG AS. [less ▲]

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See detailLow-frequency coherent fluctuations in BOLD activity: a preliminary report
Garraux, Gaëtan ULg; Guido, Nolte; Mark, Hallett

Poster (2004)

Background Low frequency (<0.1Hz) fluctuations originating from blood flow and oxygenation have been observed in the brain by different groups (Golanov et al. 1994; Biswal.et al. 1995). The goal of this ... [more ▼]

Background Low frequency (<0.1Hz) fluctuations originating from blood flow and oxygenation have been observed in the brain by different groups (Golanov et al. 1994; Biswal.et al. 1995). The goal of this study was to use BOLD fMRI to characterize coherent fluctuations in those low frequencies between spatially distant brain regions. Methods Thirteen right-handed subjects were studied using blocked-design BOLD fMRI at rest and as they performed sequential finger movements at a slow rate (~0.5 Hz) with their right hand. Serial acquisitions of EPI images were obtained at 3T using a single-shot 2D gradient-echo echo-planar imaging sequence. Data were processed and analyzed using standard procedures implemented in the statistical parametric mapping software (SPM2). Temporal profile of brain activity in 6 predefined regions (left S1M1, right S1M1, SMA, left thalamus, right cerebellum and CSF) were extracted on a subject-by-subject basis using the VOI tool in SPM2. After deconvolution (Gitelman et al. 2003), time series data representing movement and resting conditions were concatenated to create 2 within-condition time-series. After subtracting the mean over all epochs from each epoch, the (complex) coherency was calculated in the 5 lowest frequency bins with a frequency resolution of 1/17.5Hz (0, 0.05, 0.11, 0.17, 0.23 Hz). Real and imaginary parts of coherency, representing correlation and correlation of phase-shifted signals, respectively, were analyzed separately. Coherency was computed independently for each region pairs and each subject. Significance was defined as p<0.05 Bonferroni corrected for multiple comparisons. Results The main finding was the presence of coherent fluctuations in BOLD signal mainly in the lowest frequencies for (almost) all regions. The real part of coherency was equally pronounced during the movement and rest conditions. The only exception was a larger coherence during rest than during the task condition in the lowest frequencies between left and right S1M1. We could not find any significant imaginary part of coherency indicating that the time delays between dependent neural activations are negligible compared to the inverse frequencies under study. Partialling out the data in any of the regions did not have any significant impact on coherence map. Importantly, there was no evidence of coherent activity between any of the brain regions and CSF in any of the frequency bands. Discussion BOLD signal recorded during different behavioral steady-states showed very similar coherent fluctuations for all regions pairs studied mainly in the lowest frequencies. Those results are in good agreement with electrophysiological recordings in monkeys in which high coherence in band-limited power of local field potential signals have been reported at very low frequencies (<0.1Hz) (Leopold et al. 2003). In that study, coherence patterns were also highly similar under distinctly different behavioral states. Task-independent coherence in lower frequencies may be related to whole brain slow synchronous oscillations whose significance remains to be elucidated. References Golanov et al. (1994). Am J Physiol. 266; R204-214. Biswal et al. (1995). Magn Reson Med. 34; 537-541. Gitelman et al. (2003). NeuroImage. 19; 200-207. Leopold. et al. (2003). Cereb Cortex. 13; 422-433. [less ▲]

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See detailLow-molecular-weight heparin dosage in newborn foals.
Armengou, L.; Monreal, L.; Delgado, M. A. et al

in Journal of veterinary internal medicine / American College of Veterinary Internal Medicine (2010), 24(5), 1190-5

BACKGROUND: Heparin is used in humans as prophylaxis of hypercoagulable states and disseminated intravascular coagulation (DIC). However, babies need a higher heparin dose than do adults. Septic neonate ... [more ▼]

BACKGROUND: Heparin is used in humans as prophylaxis of hypercoagulable states and disseminated intravascular coagulation (DIC). However, babies need a higher heparin dose than do adults. Septic neonate foals are at high risk of hypercoagulable state and DIC, and there is limited objective information about heparin dose for equine neonates. OBJECTIVE: To assess whether neonate foals require higher dosages of low-molecular-weight heparin (LMWH) than adults. ANIMALS: Eighteen healthy and 11 septic neonate foals. METHODS: Experimental and clinical studies. Firstly, healthy foals were randomly distributed in 2 groups, 1 receiving 50 IU/kg SC of dalteparin and the 2nd group receiving 100 IU/kg SC of dalteparin, once daily for 3 days. Blood samples were collected before and 3, 6, 27, and 51 hours after the 1st LMWH administration. Plasma antifactor-Xa activity was measured, together with hemostatic and hematologic parameters used to assess the risk of bleeding. Subsequently, septic foals were treated blindly either with placebo (saline) or 100 IU/kg of dalteparin for 3 days. Plasma antifactor-Xa activity and other hemostatic parameters were determined before and after treatment. RESULTS: Plasma antifactor-Xa activity in healthy foals was below prophylactic activity when using the adult dosage (50 IU/kg), whereas prophylactic activities were achieved when using the double dosage (100 IU/kg). No hemorrhagic events and erythrocyte-related complications were observed with either dosage. In the clinical study, only 4/6 septic foals had plasma antifactor-Xa activity adequate for prophylaxis. CONCLUSIONS AND CLINICAL IMPORTANCE: Equine neonates require higher dosages of LMWH compared with adults to reach prophylactic heparinemia. [less ▲]

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See detailLow-Molecular-Weight Protein Tyrosine Phosphatases of Bacillus subtilis
Musumeci, Lucia ULg; Bongiorni, Cristina; Tautz, Lutz et al

in Journal of Bacteriology (2005), 187(14), 4945-4956

In gram-negative organisms, enzymes belonging to the low-molecular-weight protein tyrosine phosphatase (LMPTP) family are involved in the regulation of important physiological functions, including stress ... [more ▼]

In gram-negative organisms, enzymes belonging to the low-molecular-weight protein tyrosine phosphatase (LMPTP) family are involved in the regulation of important physiological functions, including stress resistance and synthesis of the polysaccharide capsule. LMPTPs have been identified also in gram-positive bacteria, but their functions in these organisms are presently unknown. We cloned two putative LMPTPs from Bacillus subtilis, YfkJ and YwlE, which are highly similar to each other in primary structure as well as to LMPTPs from gram-negative bacteria. When purified from overexpressing Escherichia coli strains, both enzymes were able to dephosphorylate p-nitrophenyl-phosphate and phosphotyrosine-containing substrates in vitro but showed significant differences in kinetic parameters and sensitivity to inhibitors. Transcriptional analyses showed that yfkJ was transcribed at a low level throughout the growth cycle and underwent a σB-dependent transcriptional upregulation in response to ethanol stress. The transcription of ywlE was growth dependent but stress insensitive. Genomic deletion of each phosphatase-encoding gene led to a phenotype of reduced bacterial resistance to ethanol stress, which was more marked in the ywlE deletion strain. Our study suggests that YfkJ and YwlE play roles in B. subtilis stress resistance. [less ▲]

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See detailLow-order local modelling of structural nonlinearities
Noël, Jean-Philippe ULg; Kerschen, Gaëtan ULg

in Proceedings of the XVIIIth Symposium on Vibrations, shocks and noise (VCB 2012) (2012, July)

The present paper addresses the problem of characterising structural nonlinearities in view of system identification. A low-order local modelling strategy is proposed and encapsulated in a recently ... [more ▼]

The present paper addresses the problem of characterising structural nonlinearities in view of system identification. A low-order local modelling strategy is proposed and encapsulated in a recently-introduced frequency-domain nonlinear subspace method for the estimation of model parameters. The complete methodology is first demonstrated using two academic examples, namely a Duffing oscillator and a five-degree-of-freedom system comprising two nonlinearities. The identification of an experimental beam involving nonlinear geometrical behaviour is finally addressed. [less ▲]

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See detailLow-order models of a single-screw expander for organic Rankine cycle applications
Ziviani, Davide; Desideri, Adriano ULg; Lemort, Vincent ULg et al

in Low-order models of a single-screw expander for organic Rankine cycle applications D. (2015, September 10)

Screw-type volumetric expanders have been demonstrated to be a suitable technology for organic Rankine cycle (ORC) systems because of higher overall effectiveness and good part-load behaviour over other ... [more ▼]

Screw-type volumetric expanders have been demonstrated to be a suitable technology for organic Rankine cycle (ORC) systems because of higher overall effectiveness and good part-load behaviour over other positive displacement machines. An 11 kWe single-screw expander (SSE) adapted from an air compressor has been tested in an ORC test-rig operating with R245fa as working fluid. A total of 60 steady-steady points have been obtained at four different rotational speeds of the expander in the range between 2000 rpm and 3300 rpm. The maximum electrical power output and overall isentropic effectiveness measured were 7.3 kW and 51.9%, respectively. In this paper, a comparison between two low-order models is proposed in terms of accuracy of the predictions, the robustness of the model and the computational time. The first model is the Pacejka equation-based model and the second is a semi-empirical model derived from a well-known scroll expander model and modified to include the geometric aspects of a single screw expander. The models have been calibrated with the available steady-state measurement points by identifying the proper parameters. 1. [less ▲]

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See detailLow-productive alpha-herpesviridae infection in chronic lichenoid dermatoses
Nikkels, Arjen ULg; Sadzot-Delvaux, Catherine ULg; Rentier, Bernard ULg et al

in Dermatology : International Journal for Clinical & Investigative Dermatology (1998), 196(4), 442-446

BACKGROUND: Herpes simplex virus (HSV) and Varicella-zoster virus (VZV) are responsible for various atypical mucocutaneous manifestations in the immunosuppressed population. One of the causative ... [more ▼]

BACKGROUND: Herpes simplex virus (HSV) and Varicella-zoster virus (VZV) are responsible for various atypical mucocutaneous manifestations in the immunosuppressed population. One of the causative pathomechanisms suggests an altered virus-host cell relationship. OBJECTIVE/METHODS: This report investigates by histology, immunohistochemistry and in situ hybridization the histological and virological features of 6 protracted, indolent HSV infections and 2 prolonged zoster infections. RESULTS: Histopathology revealed a lichenoid dermatitis in all patients. Specific HSV-1, HSV-2 and VZV in situ hybridization proved the viral origin of the cutaneous lesions. Immunohistochemical assessment demonstrated the intracellular presence of the HSV glycoproteins gB, gC and gD in epidermal keratinocytes which did not exhibit cytolysis. Similar findings were obtained for the VZV gE and gB. CONCLUSION: These results suggest that in some instances HSV and VZV infections may present a protracted disease course associated with a lichenoid inflammatory pattern and a non-cytolytic virus-host cell relationship. [less ▲]

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See detailLow-rank optimization for distance matrix completion
Mishra, Bamdev ULg; Meyer, Gilles ULg; Sepulchre, Rodolphe ULg

in Proceedings of the 50th IEEE Conference on Decision and Control (2011, December)

This paper addresses the problem of low-rank distance matrix completion. This problem amounts to recover the missing entries of a distance matrix when the dimension of the data embedding space is possibly ... [more ▼]

This paper addresses the problem of low-rank distance matrix completion. This problem amounts to recover the missing entries of a distance matrix when the dimension of the data embedding space is possibly unknown but small compared to the number of considered data points. The focus is on high-dimensional problems. We recast the considered problem into an optimization problem over the set of low-rank positive semidefinite matrices and propose two efficient algorithms for low-rank distance matrix completion. In addition, we propose a strategy to determine the dimension of the embedding space. The resulting algorithms scale to high-dimensional problems and monotonically converge to a global solution of the problem. Finally, numerical experiments illustrate the good performance of the proposed algorithms on benchmarks. [less ▲]

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See detailLow-rank optimization on the cone of positive semidefinite matrices
Journee, Michel ULg; Bach, F.; Absil, P.-A. et al

in SIAM Journal on Optimization (2010), 20(5)

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See detailLow-rank optimization with trace norm penalty
Mishra, Bamdev ULg; Meyer, Gilles ULg; Bach, Francis et al

E-print/Working paper (2012)

The paper addresses the problem of low-rank trace norm minimization. We propose an algorithm that alternates between fixed-rank optimization and rank-one updates. The fixed-rank optimization is ... [more ▼]

The paper addresses the problem of low-rank trace norm minimization. We propose an algorithm that alternates between fixed-rank optimization and rank-one updates. The fixed-rank optimization is characterized by an efficient factorization that makes the trace norm differentiable in the search space and the computation of duality gap numerically tractable. The search space is nonlinear but is equipped with a particular Riemannian structure that leads to efficient computations. We present a second-order trust-region algorithm with a guaranteed quadratic rate of convergence. Overall, the proposed optimization scheme converges super-linearly to the global solution while still maintaining complexity that is linear in the number of rows of the matrix. To compute a set of solutions efficiently for a grid of regularization parameters we propose a predictor-corrector approach on the quotient manifold that outperforms the naive warm-restart approach. The performance of the proposed algorithm is illustrated on problems of low-rank matrix completion and multivariate linear regression. [less ▲]

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See detailLow-rank plus sparse decomposition for exoplanet detection in direct-imaging ADI sequences. The LLSG algorithm
Gómez González, Carlos ULg; Absil, Olivier ULg; Absil, P.-A. et al

in Astronomy and Astrophysics (2016), 589

Context. Data processing constitutes a critical component of high-contrast exoplanet imaging. Its role is almost as important as the choice of a coronagraph or a wavefront control system, and it is ... [more ▼]

Context. Data processing constitutes a critical component of high-contrast exoplanet imaging. Its role is almost as important as the choice of a coronagraph or a wavefront control system, and it is intertwined with the chosen observing strategy. Among the data processing techniques for angular differential imaging (ADI), the most recent is the family of principal component analysis (PCA) based algorithms. It is a widely used statistical tool developed during the first half of the past century. PCA serves, in this case, as a subspace projection technique for constructing a reference point spread function (PSF) that can be subtracted from the science data for boosting the detectability of potential companions present in the data. Unfortunately, when building this reference PSF from the science data itself, PCA comes with certain limitations such as the sensitivity of the lower dimensional orthogonal subspace to non-Gaussian noise. <BR /> Aims: Inspired by recent advances in machine learning algorithms such as robust PCA, we aim to propose a localized subspace projection technique that surpasses current PCA-based post-processing algorithms in terms of the detectability of companions at near real-time speed, a quality that will be useful for future direct imaging surveys. <BR /> Methods: We used randomized low-rank approximation methods recently proposed in the machine learning literature, coupled with entry-wise thresholding to decompose an ADI image sequence locally into low-rank, sparse, and Gaussian noise components (LLSG). This local three-term decomposition separates the starlight and the associated speckle noise from the planetary signal, which mostly remains in the sparse term. We tested the performance of our new algorithm on a long ADI sequence obtained on β Pictoris with VLT/NACO. <BR /> Results: Compared to a standard PCA approach, LLSG decomposition reaches a higher signal-to-noise ratio and has an overall better performance in the receiver operating characteristic space. This three-term decomposition brings a detectability boost compared to the full-frame standard PCA approach, especially in the small inner working angle region where complex speckle noise prevents PCA from discerning true companions from noise. [less ▲]

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See detailLow-temperature chemical vapor deposition of highly-doped n-type epitaxial Si at high growth rate
Nguyen, Ngoc Duy ULg; Loo, Roger; Caymax, Matty

Conference (2007)

We investigated the growth of in-situ n-type doped epitaxial Si layers with arsenic and phosphorus by means of low-temperature chemical vapor deposition using trisilane as Si-precursor. Indeed, in order ... [more ▼]

We investigated the growth of in-situ n-type doped epitaxial Si layers with arsenic and phosphorus by means of low-temperature chemical vapor deposition using trisilane as Si-precursor. Indeed, in order to prevent the alteration of the characteristics of the devices which are already present on the wafer, an epitaxy process at low temperature is highly desired for applications such as BiCMOS. In this work, the varying parameters are the deposition temperature, the Si-precursor mass flow and the dopant gas flow. As a result, a process for the deposition of heavily doped epilayers was demonstrated at 600 °C with high deposition rate, which is important for maintaining high throughput and low process cost. We showed that using trisilane as a Si-precursor resulted in a much more linear n-type doping behavior than using dichlorosilane. Therefore it allowed an easier process control and a wider dynamic doping range. Our process is an interesting route for the epitaxy of a low-resistance emitter layer for bipolar transistor application. [less ▲]

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