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1.
Behav Res Methods ; 51(2): 532-555, 2019 04.
Article in English | MEDLINE | ID: mdl-30334149

ABSTRACT

This paper introduces a new experimental protocol for studying mental representations of urban soundscapes through a simulation process. Subjects are asked to create a full soundscape by means of a dedicated software tool, coupled with a structured sound data set. This paradigm is used to characterize urban sound environment representations by analyzing the sound classes that were used to simulate the auditory scenes. A rating experiment of the soundscape pleasantness using a seven-point bipolar semantic scale is conducted to further refine the analysis of the simulated urban acoustic scenes. Results show that (1) a semantic characterization in terms of presence/absence of sound sources is an effective way to characterize urban soundscape pleasantness, and (2) acoustic pressure levels computed for specific sound sources better characterize the appraisal than the acoustic pressure level computed over the overall soundscape.


Subject(s)
Acoustics , Auditory Perception , Emotions , Humans , Semantics , Sound
2.
Nanotechnology ; 28(5): 055709, 2017 Feb 03.
Article in English | MEDLINE | ID: mdl-28032620

ABSTRACT

Silver nanowire (AgNW) networks are emerging as one of the most promising alternatives to indium tin oxide (ITO) for transparent electrodes in flexible electronic devices. They can be used in a variety of optoelectronic applications such as solar cells, touch panels and organic light-emitting diodes. Recently they have also proven to be very efficient when used as transparent heaters (THs). In addition to the study of AgNW networks acting as THs in regular use, i.e. at low voltage and moderate temperature, their stability and physical behavior at higher voltages and for longer durations should be studied in view of their integration into real devices. The properties of AgNW networks deposited by spray coating on glass or flexible transparent substrates are thoroughly studied via in situ measurements. The AgNW networks' behavior at different voltages for different durations and under different atmospheric conditions, both in air and under vacuum, has been examined. At low voltage, a reversible electrical response is observed while irreversibility and even failure are observed at higher voltages. In order to gain a deeper insight into the behavior of AgNW networks used as THs, simple but realistic physical models are proposed and are found to be in fair agreement with the experimental data. Finally, as the stability of AgNW networks is a key issue, we demonstrate that coating AgNW networks with a very thin layer of TiO2 using atomic layer deposition (ALD) improves the material's resistance against electrical and thermal instabilities without altering optical transmittance. We show that the critical annealing temperature associated to network breakdown increases from 270 °C for the as-deposited AgNW networks to 420 °C for AgNW networks coated with TiO2. Similarly, the electrical failure which occurs at 7 V for the as-deposited networks increases to 13 V for TiO2-coated networks. TiO2 is also proved to stabilize AgNW networks during long duration operation and at high voltage. Temperature higher than 235 °C was achieved at 7 V without failure.

3.
Nanoscale ; 7(41): 17410-23, 2015 Nov 07.
Article in English | MEDLINE | ID: mdl-26437607

ABSTRACT

Silver nanowire (AgNW) networks are efficient as flexible transparent electrodes, and are cheaper to fabricate than ITO (Indium Tin Oxide). Hence they are a serious competitor as an alternative to ITO in many applications such as solar cells, OLEDs, transparent heaters. Electrical and optical properties of AgNW networks deposited on glass are investigated in this study and an efficient method to optimize them is proposed. This paper relates network density, nanowire dimensions and thermal annealing directly to the physical properties of the nanowire networksusing original physical models. A fair agreement is found between experimental data and the proposed models. Moreover thermal stability of the nanowires is a key issue in thermal optimization of such networks and needs to be studied. In this work the impact of these four parameters on the networks physical properties are thoroughly investigated via in situ measurements and modelling, such a method being also applicable to other metallic nanowire networks. We demonstrate that this approach enables the optimization of both optical and electrical properties through modification of the junction resistance by thermal annealing, and a suitable choice of nanowire dimensions and network density. This work reports excellent optical and electrical properties of electrodes fabricated from AgNW networks with a transmittance T = 89.2% (at 550 nm) and a sheet resistance of Rs = 2.9 Ω â–¡(-1), leading to the highest reported figure of merit.

4.
Nanoscale ; 6(22): 13535-43, 2014 Nov 21.
Article in English | MEDLINE | ID: mdl-25267592

ABSTRACT

Metallic nanowire networks have huge potential in devices requiring transparent electrodes. This article describes how the electrical resistance of metal nanowire networks evolve under thermal annealing. Understanding the behavior of such films is crucial for the optimization of transparent electrodes which find many applications. An in-depth investigation of silver nanowire networks under different annealing conditions provides a case study demonstrating that several mechanisms, namely local sintering and desorption of organic residues, are responsible for the reduction of the systems electrical resistance. Optimization of the annealing led to specimens with transmittance of 90% (at 550 nm) and sheet resistance of 9.5 Ω sq(-1). Quantized steps in resistance were observed and a model is proposed which provides good agreement with the experimental results. In terms of thermal behavior, we demonstrate that there is a maximum thermal budget that these electrodes can tolerate due to spheroidization of the nanowires. This budget is determined by two main factors: the thermal loading and the wire diameter. This result enables the fabrication and optimization of transparent metal nanowire electrodes for solar cells, organic electronics and flexible displays.

5.
Rev Neurol (Paris) ; 165(1): 48-51, 2009 Jan.
Article in French | MEDLINE | ID: mdl-18835614

ABSTRACT

INTRODUCTION: We are reporting 23 cases of patients presenting neurological symptoms in the setting of a chikungunya outbreak that occurred in the Indian Ocean from March 2005 to April 2006. These symptoms were the cause of admission in our ward, mainly via the emergency room. CASE REPORTS: In the acute phase of their illness, 23 patients presented neurological symptoms associated with positive CSF tests (specific IgM or RT- PCR). Clinical manifestations included disrupted behavior or altered mental status in 95% of patients, headache in 30.4%, seizure in 26%, motor dysfunction in 4.3% and sensorial disorders in 8.7%. Outcome was fatal in two patients during their hospitalisation and several months after discharge in three other elderly bedridden patients with altered general status. CSF analysis was sometimes but not always inflammatory. CT or MRI, when done, showed no recent abnormality. EEG disclosed most often of a diffuse moderately slowed activity with no pseudo-periodic or unusual pattern. A few epileptic aspects were seen in known epileptic patients. The outcome of the neurological symptoms was generally good over a few days, contrasting with persisting impairment of general status and severe joint pains leading to a bedridden state and death in three patients. CONCLUSION: Nervous system involvement was not uncommon during the chikungunya outbreak in Reunion Island in 2005 and 2006. The most frequent expression was moderate confusion occurring during the acute phase of infection. Peripheral nerve involvement in the form of a typical Guillain Barré syndrome was also observed. In general, the neurological outcome was very good. Fatal issues occurring in the early stages or later on (five out of 23 patients) were related to altered general condition in debilitated bedridden elderly patients.


Subject(s)
Alphavirus Infections/complications , Alphavirus Infections/pathology , Chikungunya virus , Nervous System Diseases/etiology , Nervous System Diseases/pathology , Adult , Aged , Aged, 80 and over , Alphavirus Infections/cerebrospinal fluid , Electroencephalography , Epilepsy/etiology , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Nervous System Diseases/cerebrospinal fluid , Neurologic Examination , Reunion , Reverse Transcriptase Polymerase Chain Reaction , Tomography, X-Ray Computed , Young Adult
6.
Rev Neurol (Paris) ; 162(2): 229-32, 2006 Feb.
Article in French | MEDLINE | ID: mdl-16518264

ABSTRACT

In Churg and Strauss syndrome (CSS), three patterns of neurological involvement can be found, including mono or polyneuropathy, encephalopathy and stroke. We report two cases of stroke associated with major hypereosinophilia and cardiac involvement, leading to a diagnosis of CSS. Neurological and general outcome were good under treatment with steroids in combination with cyclophosphamide in one case. Churg and Strauss syndrome must be considered when a stroke is associated with a cardiac involvement and hypereosinophilia.


Subject(s)
Brain Ischemia/etiology , Churg-Strauss Syndrome/physiopathology , Heart Diseases/etiology , Adrenal Cortex Hormones/therapeutic use , Adult , Brain/pathology , Brain Ischemia/pathology , Churg-Strauss Syndrome/pathology , Female , Humans , Hypereosinophilic Syndrome/etiology , Magnetic Resonance Imaging , Middle Aged , Treatment Outcome
7.
Br J Cancer ; 87(6): 630-4, 2002 Sep 09.
Article in English | MEDLINE | ID: mdl-12237773

ABSTRACT

The gene for the transducer of transforming growth factor-beta/bone morphogenetic protein signalling SMAD4, a potential suppressor of colorectal carcinogenesis, is located at the chromosomal region 18q21. In order to evaluate the clinical relevance of SMAD4 deletion, gene copy alterations were determined by copy dosage using real-time quantitative PCR in 202 colorectal tumour biopsies from a previous randomised study of adjuvant chemotherapy. Patients with normal SMAD4 diploidy turned out to have a three-fold higher benefit of 5-fluorouracil-based adjuvant chemotherapy with a border line significance (overall survival: 3.23, P=0.056; disease-free survival: 2.89, P=0.045). These data are consistent with the previous observation that patients whose cancer had retention of the 18q21 region had a significantly higher benefit from 5-fluorouracil-based therapy. Moreover, these results may provide a refinement at the gene level of the clinical relevance of 18q21 deletion, thereby suggesting SMAD4 as a predictive marker in colorectal cancer. This data also indicate that integrity of this component of the transforming growth factor-beta/bone morphogenetic protein signalling pathway may be a critical factor for benefit of chemotherapy in patients with colorectal cancer.


Subject(s)
Antimetabolites, Antineoplastic/therapeutic use , Chromosomes, Human, Pair 18/genetics , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/genetics , DNA-Binding Proteins/genetics , Fluorouracil/therapeutic use , Gene Dosage , Trans-Activators/genetics , Biomarkers , Chemotherapy, Adjuvant , Chromosome Deletion , DNA Primers/chemistry , DNA, Neoplasm/metabolism , Female , Gene Expression Regulation, Neoplastic , Humans , Male , Middle Aged , Polymerase Chain Reaction , Predictive Value of Tests , Prognosis , Randomized Controlled Trials as Topic , Signal Transduction/genetics , Smad4 Protein , Survival Rate , Transforming Growth Factor beta/genetics
10.
Genes Chromosomes Cancer ; 31(3): 240-7, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11391794

ABSTRACT

Deletions of chromosome band 18q21 appear with very high frequency in a variety of carcinomas, especially in colorectal cancer. Potent tumor suppressor genes located in this region encode transforming growth factor beta (TGF-beta) signal transducers SMAD2 and SMAD4, and inactivation of either one leads to impaired TGF-beta-mediated cell growth/apoptosis. Following the assignment of SMAD7 to 18q21, we first refined the SMAD7 gene position within this region by genetically mapping SMAD7 between SMAD2 and SMAD4. Further, to compare the respective frequencies of genetic alterations of these three SMAD genes in colorectal cancer, we undertook a large-scale evaluation of the copy status of each of these genes on DNA samples from colorectal tumor biopsy material. Among a subset of 233 DNA samples for which data were available for all four genes, SMAD4, SMAD2, and the nearby gene DCC showed high deletion rates (66%, 64%, and 59%, respectively), whereas SMAD7 was deleted in only 48% of the tumors. Unexpectedly, we found some gene duplications; SMAD7 appears to be more frequently amplified (10%) than the three other genes (4-7%). Compiled data for SMAD genes in each tumor show that the most common combination (26% of all the tumors) consists of the simultaneous deletions of SMAD2 and SMAD4 associated with normal diploidy or even duplication of SMAD7. Since SMAD7 normally counteracts SMAD2 and SMAD4 in TGF-beta signaling, we hypothesize that the tumor might not benefit from simultaneous SMAD7 inactivation, thereby exerting selective pressure to retain or even to duplicate the SMAD7 gene.


Subject(s)
Chromosomes, Human, Pair 18/genetics , Colorectal Neoplasms/genetics , DNA-Binding Proteins/genetics , Gene Dosage , Trans-Activators/genetics , Chromosome Deletion , Chromosome Mapping , Gene Order , Genes, Overlapping/genetics , Genes, Tumor Suppressor/genetics , Humans , Signal Transduction/genetics , Smad2 Protein , Smad4 Protein , Smad7 Protein , Transforming Growth Factor beta/genetics
13.
Br J Haematol ; 103(2): 488-94, 1998 Nov.
Article in English | MEDLINE | ID: mdl-9827924

ABSTRACT

T-prolymphocytic leukaemia (T-PLL) is a rare disorder with a poor outcome. Presentation features were studied in 78 T-PLL cases. Although 53 patients (group A) presented with typical progressive disease including rapidly increasing leucocytosis. 25 patients (group B) experienced an initial indolent clinical course with stable moderate leucocytosis. The morphology and antigenic profile of abnormal cells were similar in both groups, except for a lower incidence of CD45RO+ CD45RA- pattern in group B. A high incidence of inv(14)(q11;q32), t(14;14)(q11;q32) and i(8)(q10) chromosomal abnormalities were found in both groups. After an initial indolent phase (median 33 months; 6-103 months), 16 group B patients progressed to an aggressive stage with clinical and laboratory features similar to group A. Moreover, median survival after progression was short in both groups. In conclusion, T-PLL may start as an indolent disease similar to that reported in ataxia telangectasia. In this rare genetic disorder, some patients develop stable T-cell clones which progress toward T-PLL-like leukaemia. Moreover, ATM gene mutations have been reported in T-PLL. Thus, both diseases are likely to be closely related.


Subject(s)
Leukemia, Prolymphocytic, T-Cell/diagnosis , Leukemia, Prolymphocytic/diagnosis , Adult , Aged , Aged, 80 and over , Chromosome Aberrations , Disease Progression , Female , Follow-Up Studies , Humans , Immunophenotyping , Leukemia, Prolymphocytic/immunology , Leukemia, Prolymphocytic/pathology , Leukemia, Prolymphocytic, T-Cell/immunology , Leukemia, Prolymphocytic, T-Cell/pathology , Male , Middle Aged , Prognosis , Retrospective Studies , Survival Rate
14.
Muscle Nerve ; 20(8): 953-60, 1997 Aug.
Article in English | MEDLINE | ID: mdl-9236785

ABSTRACT

We have shown recently that cocultures of muscle cells from infantile spinal muscular atrophy (SMA) patients innervated by motoneurons of normal rat spinal cord explants undergo a degeneration process, suggesting that muscle may play a role in this atrophy, which previously has been considered to be a pure motoneuron disease. Conditional media of SMA cocultures did not affect control healthy nerve muscle cocultures. Conversely, conditioned media of control cocultures were unable to prevent degeneration of SMA cocultures. Moreover, neurotrophic factors, thought to be of help in motoneuron disease treatment, did not protect SMA cocultures from premature death. Our results suggest that the abnormal phenotype observed in nerve-muscle coculture (1) is not due to the release of a toxic factor nor to the lack of a secreted survival factor, and (2) does not respond to neurotrophin treatment.


Subject(s)
Muscle Fibers, Skeletal/cytology , Muscle Fibers, Skeletal/metabolism , Muscular Atrophy, Spinal/metabolism , Nerve Growth Factors/pharmacology , Spinal Cord/cytology , Animals , Brain-Derived Neurotrophic Factor/pharmacology , Cell Culture Techniques/methods , Humans , Motor Neurons/chemistry , Motor Neurons/cytology , Muscle Fibers, Skeletal/chemistry , Muscular Atrophy, Spinal/genetics , Nerve Degeneration/drug effects , Nerve Degeneration/physiology , Neuroprotective Agents/pharmacology , Neurotrophin 3 , Phenotype , Rats , Receptors, Cholinergic/analysis
15.
J Clin Pathol ; 50(3): 206-11, 1997 Mar.
Article in English | MEDLINE | ID: mdl-9155670

ABSTRACT

AIMS: To determine whether the presence of disseminated bone marrow tumour cells at diagnosis is a prognostic factor for breast cancer patients at high risk of recurrence or bone metastasis, and to assess their presence as a criterion for evaluation of the potential benefits of adjuvant chemotherapy. METHODS: Multiple bone marrow aspirates from 72 breast cancer patients free from metastasis were obtained during surgery at the time of diagnosis and were tested immunologically by alkaline phosphatase antialkaline phosphatase technique with a panel of three antiepithelial monoclonal antibodies (MoAb) KL1, EMA, and HMFG2. RESULTS: In nine of 72 patients, with each MoAb tested, numerous strongly positive cells always isolated were observed. However, it was demonstrated that these cells were non-specifically labelled and could be found in normal controls. CONCLUSIONS: There was no evidence of marrow tumour cells in 72 operable breast cancer patients. It is suggested that published results may be greatly overestimated and that non-specific labelling may be undetected. More specific MoAb should be found and a correlation with molecular biology should be performed if this criterion is to be considered as a prognostic factor.


Subject(s)
Bone Marrow Neoplasms/pathology , Bone Marrow Neoplasms/secondary , Breast Neoplasms/pathology , Adult , Aged , Aged, 80 and over , Bone Marrow/pathology , Female , Follow-Up Studies , Histological Techniques , Humans , Immunohistochemistry , Middle Aged , Sensitivity and Specificity , Stromal Cells/pathology
16.
J. bras. psiquiatr ; 45(9): 519-521, set. 1996.
Article in Portuguese | LILACS | ID: lil-306912

ABSTRACT

O presente artigo tem como objetivo apresentar o Projeto Censo Psiquiátrico que será desenvolvido no Município do Rio de Janeiro. Este projeto abrangerá toda a população de pacientes psiquiátricos sob às expensas do SUS (Sistema Único de Saúde). Descreverá as circunstâncias às quais foi concebido, sua operacionalização e seus objetivos. Tendo este último como principais finalidades realizar um perfil sócio-econômico e clínico acerca da população, a fim de subsidiar o planejamento da assistência em saúde mental no Município


Subject(s)
Humans , Censuses , Hospitals, Psychiatric , Inpatients , Brazil , Surveys and Questionnaires
17.
J Chir (Paris) ; 133(2): 65-71, 1996 Apr.
Article in French | MEDLINE | ID: mdl-8763563

ABSTRACT

Our series of 500 consecutive laparoscopic cholecystectomies has drawn attention to several factors. Results would favor endoscopic sphincterotomy in cases with associated treatment of gall stones in the main bile duct. history taking should search for past history of laparoscopic surgery, especially in men with an extensive pillosity, work-up should include ultrasonography, liver function tests and intravenous cholangiography (in all patients excepting cases of allergy), it is important to use an identical material in a given hospital facility for identical procedures in order to avoid equipment-related conversions, an interesting alternative in emergency situations would be echo-guided transcutaneous transperietal cholecystotomy which allows time for safe opacification, safety is of prime importance and rapide conversion should be made when there is any doubt, especially concerning the main duct, morbidity and mortality in this series were nearly identical to those previously reported large series, for endoscopic sphincterotomy proposed as complementary therapy for cases with associated lithiasis in the main bile duct, 2/3 were performed peroperatively and 1/3 postoperatively. Considering all sphincterotomies, 2/3 were positive with extraction of a stone and demonstration of an enlarged bile duct evidencing recent migration (no failure or iatrogenic event), the relationship between the different elements should allow rapid indications in emergency situations and identify complications immediately (mean hospitalization less than 48 hours) or later. Finally, first intention laparoscopic cholecystectomy can be proposed for patients with signs of biliary distress with lithiasis depite other, sometimes contradictory, conclusions (ANDEM, CPAM, consensus conference). First intention laparoscopic cholecystectomy should eliminate in the future most of the major biliary-pancreatic abdominal syndromes.


Subject(s)
Cholecystectomy, Laparoscopic/methods , Cholelithiasis/surgery , Gallstones/surgery , Sphincterotomy, Endoscopic/methods , Adolescent , Adult , Aged , Aged, 80 and over , Child , Cholangiopancreatography, Endoscopic Retrograde , Cholelithiasis/diagnostic imaging , Female , Gallstones/diagnostic imaging , Humans , Laparotomy , Male , Middle Aged , Postoperative Complications
19.
J Neurol Sci ; 136(1-2): 17-23, 1996 Mar.
Article in English | MEDLINE | ID: mdl-8815167

ABSTRACT

Neurotrophins, nerve growth factor (NGF), neurotrophin-3 (NT-3), neurotrophin-5 (NT-5) and brain-derived neurotrophic factor (BDNF), were studied in vitro in a coculture model of human skeletal muscle myotubes and rat embryo spinal cord explants, which enables the different steps of functional innervation to be followed, including neurite outgrowth, synapse formation and induction of contractile activity. We found that NT-3, NT-5, BDNF, but not NGF simultaneously induced a significant increase in the number and length of neurites emerging from spinal cord explants, the number of endplates per muscle fiber, and the area of innervated muscle fibers around each spinal cord explant. These results suggest that neurotrophins NT-3, NT-5 and BDNF enhance spinal cord motoneurons potential of innervation.


Subject(s)
Motor Neurons/drug effects , Muscle Fibers, Skeletal/physiology , Muscles/innervation , Neuropeptides/pharmacology , Spinal Cord/physiology , Animals , Brain-Derived Neurotrophic Factor , Cell Count , Cells, Cultured , Coculture Techniques , Humans , Motor Neurons/ultrastructure , Muscle Fibers, Skeletal/ultrastructure , Nerve Growth Factors/pharmacology , Nerve Tissue Proteins/pharmacology , Neurites/physiology , Neurites/ultrastructure , Neurotrophin 3 , Rats , Spinal Cord/cytology
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