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1.
Rev Sci Instrum ; 88(2): 026102, 2017 Feb.
Article in English | MEDLINE | ID: mdl-28249500

ABSTRACT

We have achieved distributed feedback laser diode line narrowing by simultaneously acting on the diode current via a feed-back loop and on an external electrooptic phase modulator in feed-forward actuator. This configuration turns out to be very efficient in reaching large bandwidth in the phase correction: up to 15 MHz with commercial laser control units. About 98% of the laser power undergoes narrowing. The full width at half maximum of the narrowed optical spectrum is of less than 4 kHz. This configuration appears to be very convenient as the delay in the feed-forward control electronics is easily compensated for by a 20 m optical fiber roll.

2.
Encephale ; 42(5): 421-425, 2016 Oct.
Article in French | MEDLINE | ID: mdl-27017316

ABSTRACT

INTRODUCTION: In 2013, the American Psychiatric Association published the DSM-5. In this new version, new diagnoses were proposed including the Hoarding disorder. In the French semeiology, the Diogenes syndrome is described, among other symptoms, by a pathological tendency to accumulate objects called syllogomania which is very close to hoarding. This paper explores the similarities and differences between the two syndromes. DESCRIPTION: The Diogenes syndrome was first described in 1966 but was officially named for the ancient Greek philosopher in 1975 by Clark. Its frequency is around five for 100,000 persons. Many aetiologies have been known to be associated with the Diogenes syndrome: schizophrenia, dementia - especially frontotemporal type, anxiety disorders, mood disorders, and substance abuse - especially alcohol abuse. The diagnostic requires one major criterion, the inability to ask for medical or social help, and one of three minor criteria: a pathological relationship to the body, which leads to somatic illness; a pathological relationship to the society, which leads to a progressive exclusion from it; and finally, a pathological link with objects. This last criterion is very interesting because it is closely related to the Hoarding syndrome: indeed, patients with syllogamania, as also named, have a tendency to hoard every object they find. At the end, their homes are full of useless objects, and some living places can be unusable because they are cluttered and congested. This last point is similar to the definition given in the DSM-5 for the Hoarding disorder which describes a persistent difficulty parting with possessions; distress associated with discarding possessions; and accumulations that congest and clutter active living areas. The Hoarding disorder was first part of the Obsessive and compulsive disorders, but it has progressively appeared that it could be individualized with its own prevalence of 2.3% to 14% lifetime. Genetical studies have shown that at least 50% of patients suffering from excessive hoarding had a relative with a dimension of hoarding. Finally, Mattaix-Cols et al. decided to create a new syndrome in the DSM-5, and the Hoarding disorder was born. DISCUSSION: The discussion begins with relationships between the Hoarding disorder and the Diogenes syndrome. A patient with hoarding, and a poor insight, could be very isolated, and could persist in a lack of calling for help, because of not being aware of his pathology. Thus, it could be diagnosed as a Hoarding syndrome with a poor insight, or as a Diogenes syndrome, with the first major criterion (lack of calling for help) and one of the three minor criteria, the syllogomania, or hoarding. Moreover, some authors have described old people living for many years with a tendency to hoard. Progressively, some of them had a congested and cluttered home, and a few were living in squalor, a description very close to the Diogenes syndrome. Finally, we discuss the comorbidity of Hoarding disorder and Diogenes syndrome. In particular, the first one is associated with Attention deficit and hyperactivity disorders; and some authors also described the links between ADHD, bipolar disorder and frontotemporal dementia which is one of the aetiologies of the Diogenes syndrome. A psychodynamic model in which ADHD, Hoarding disorder and Diogenes syndrome are linked can be imagined, and the last one could be an overlooked evolution of the two first syndromes. CONCLUSION: In conclusion, we can imagine a dimensional model, based on two dimensions: hoarding and squalor. Hoarding disorder is the major expression of the first dimension, and Diogenes syndrome the major expression of the second. Both of them could be a different expression of one central aetiology. More studies are needed to complete this vision.


Subject(s)
Anxiety Disorders/psychology , Hoarding Disorder/psychology , Anxiety Disorders/classification , Diagnosis, Differential , Hoarding Disorder/classification , Humans , Psychiatric Status Rating Scales , Syndrome
3.
Opt Lett ; 40(12): 2676-9, 2015 Jun 15.
Article in English | MEDLINE | ID: mdl-26076234

ABSTRACT

We demonstrate a nanosecond single-frequency nested cavity optical parametric oscillator (NesCOPO) based on orientation-patterned GaAs (OP-GaAs). Its low threshold energy of 10 µJ enables to pump it with a pulsed single-frequency Tm:YAP microlaser. Stable single-longitudinal-mode emission is obtained owing to Vernier spectral filtering provided by the dual-cavity doubly-resonant NesCOPO scheme. Crystal temperature tuning covers the 10.3-10.9 µm range with a quasi-phase-matching period of 72.6 µm. A first step toward the implementation of this device in a differential absorption lidar is demonstrated by carrying out short-range standoff detection of ammonia vapor around 10.4 µm. Owing to the single-frequency emission, interferences due to absorption by atmospheric water vapor can be discriminated from the analyte signal.

4.
Rev Sci Instrum ; 86(3): 033104, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25832208

ABSTRACT

In this paper, we describe the design and the main performances of the PHARAO laser source flight model. PHARAO is a laser cooled cesium clock specially designed for operation in space and the laser source is one of the main sub-systems. The flight model presented in this work is the first remote-controlled laser system designed for spaceborne cold atom manipulation. The main challenges arise from mechanical compatibility with space constraints, which impose a high level of compactness, a low electric power consumption, a wide range of operating temperature, and a vacuum environment. We describe the main functions of the laser source and give an overview of the main technologies developed for this instrument. We present some results of the qualification process. The characteristics of the laser source flight model, and their impact on the clock performances, have been verified in operational conditions.

5.
Opt Express ; 22(9): 10792-9, 2014 May 05.
Article in English | MEDLINE | ID: mdl-24921779

ABSTRACT

Multi-wavelength operation of Q-switched Nd-doped YGd(2)Sc(2)Al(2)GaO(12) garnet ceramic lasers has been investigated. Dual-wavelength emission around ~1.06 µm has been demonstrated both in the actively and passively Q-switched configurations. The ratio of output energy between the two laser wavelengths was driven by the temperature elevation caused by pumping. Passively Q-switched operation yields dual-frequency emission of two unsynchronized laser pulses carried by distinct transverse modes whereas active Q-switched configuration offers the possibility of synchronizing emission at the two wavelengths.

7.
Mol Ecol ; 18(18): 3903-17, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19709370

ABSTRACT

The use of sequence polymorphism from individual mitochondrial genes to infer past demography has recently proved controversial because of the recurrence of selective sweeps acting over genes and the need for unlinked multilocus data sets. However, comparative analyses using several species for one gene and/or multiple genes for one species can serve as a test for potential selective effects and clarify our understanding of historical demographic effects. This study compares nucleotide polymorphisms in mitochondrial cytochrome oxidase I across seven deep-sea hydrothermal vent species that live along the volcanically active East Pacific Rise. Approximate Bayesian Computation (ABC) method, developed to trace shared vicariant events across species pairs, indicates the occurrence of two across species divergence times, and suggests that the present geographical patterns of genetic differentiation may be explained by two periods of significant population isolation. The oldest period dates back 11.6 Ma and is associated with the vent limpet Lepetodrilus elevatus, while the most recent period of isolation is 1.3 Ma, which apparently affected all species examined and coincides with a transition zone across the equator. Moreover, significant negative Tajima's D and star-like networks were observed for all southern lineages, suggesting that these lineages experienced a concomitant demographic and geographical expansion about 100 000-300 000 generations ago. This expansion may have initiated from a wave of range expansions during the secondary colonization of new sites along the Southern East Pacific Rise (founder effects below the equator) or recurrent bottleneck events because of the increase of eruptive phases associated with the higher spreading rates of the ridge in this region.


Subject(s)
Evolution, Molecular , Gastropoda/genetics , Genetic Speciation , Phylogeny , Polychaeta/genetics , Animals , Bayes Theorem , DNA, Mitochondrial/genetics , Electron Transport Complex IV/genetics , Gastropoda/classification , Genetics, Population , Geography , Haplotypes , Pacific Ocean , Polychaeta/classification , Sequence Analysis, DNA , Species Specificity
8.
Gene ; 406(1-2): 99-107, 2007 Dec 30.
Article in English | MEDLINE | ID: mdl-17707599

ABSTRACT

A multilocus analysis was initiated in order to infer the general effect of demography and the indirect effect of positive selection on some chromosome segments in Bathymodiolus. Mussels of the genus Bathymodiolus inhabit the very hostile, fragmented and variable environment of deep-sea hydrothermal vents which is thought to cause recurrent population bottlenecks via extinction/colonisation processes and adaptation to new environmental conditions. In the course of this work we discovered that the assumption of neutrality of non-coding polymorphisms usually made in genome scan experiments was likely to be violated at one of the loci we analysed. The direct effect of slight purifying selection on non-coding polymorphisms shares many resemblances with the indirect effect of positive selection through genetic hitchhiking. Combining polymorphism with divergence data for several closely related species allowed us to obtain different expectations for the direct effect of negative selection and the indirect effect of positive selection. We observed a strong excess of rare non-coding polymorphisms at the second intron of the EF1alpha gene in the two species Bathymodiolus azoricus and Bathymodiolus thermophilus, while two other loci, the mitochondrial COI gene and an intron of the Lysozyme gene, did not exhibit such a deviation. In addition, the divergence rate of the EF1alpha intron was estimated to be unexpectedly low when calibrated using the closure of the Panama Isthmus that interrupted gene flow between the two species. The polymorphism to divergence ratio was similar to the one observed for the other two loci, in accordance to the hypothesis of purifying selection. We conclude that slight purifying selection is likely to act on polymorphic intronic mutations of the EF1alpha second intron and discuss the possible relationship with the specific biology of Bathymodiolus mussels.


Subject(s)
Bivalvia/genetics , Introns , Peptide Elongation Factor 1/genetics , Polymorphism, Genetic , Animals , DNA, Mitochondrial , Genetic Variation , Polymerase Chain Reaction , Selection, Genetic , Sequence Analysis, DNA
9.
FEMS Microbiol Lett ; 209(1): 57-62, 2002 Mar 19.
Article in English | MEDLINE | ID: mdl-12007654

ABSTRACT

During a screening procedure for the discovery of a strong gamma-decalactone producer from ricinoleic acid, we observed that the yeast Pichia guilliermondii accumulated transiently 8-hydroxy-3Z,5Z-tetradecadienoic acid 1 during gamma-decalactone biosynthesis in the stationary phase of growth. The structural elucidation of 1 was based on nuclear magnetic resonance, infrared, ultraviolet and gas chromatography-mass spectrometry experiments. The occurrence of 1 is discussed in relation with previously proposed gamma-decalactone biosynthetic pathways.


Subject(s)
Fatty Acids, Unsaturated/isolation & purification , Hydroxy Acids/isolation & purification , Lactones/metabolism , Pichia/metabolism , Ricinoleic Acids/metabolism , Chromatography, High Pressure Liquid , Fatty Acids, Unsaturated/metabolism , Gas Chromatography-Mass Spectrometry , Hydroxy Acids/metabolism , Nuclear Magnetic Resonance, Biomolecular , Spectrophotometry, Infrared , Spectrophotometry, Ultraviolet
10.
J Microbiol Methods ; 42(3): 209-14, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11044564

ABSTRACT

A new tannase substrate, protocatechuic acid p-nitrophenyl ester, 5, was synthesized using modern synthetic methods. The synthesis was designed to be performed by non-specialized chemists. It only involves four steps, three of which are protection-deprotection, and uses standard methods of separation and purification, such as recrystallization and column chromatography over silica. Under tannase action, protocatechuic acid p-nitrophenyl ester, 5, releases p-nitrophenol, which is easily measured spectrophotometrically either at 350 nm for pH values<6 or at 400 nm for pH values of 6-7 (yellow). The pH-response and the catalytic parameters of a crude Penicillium sp. tannase preparation were determined using 5 as substrate, thus showing the usefulness of this substrate in determining tannase activity.


Subject(s)
Carboxylic Ester Hydrolases/metabolism , Hydroxybenzoates/chemical synthesis , Hydroxybenzoates/metabolism , Spectrophotometry , Hydrogen-Ion Concentration , Kinetics , Nitrophenols , Penicillium/enzymology , Spectrophotometry, Ultraviolet
11.
J Biomech ; 30(11-12): 1169-71, 1997.
Article in English | MEDLINE | ID: mdl-9456386

ABSTRACT

This study proposes to estimate the horizontal positions of the body's centre of gravity (CoG) in a standing posture, on the basis of the horizontal positions of the centre of pressure (CoP). The latter were measured with a force plate, and using a low-pass filter defined by a mathematical relationship of the relative magnitude of the CoG with respect to the magnitude of the CoP, as a function of the frequency oscillations (Brenière, 1996, Journal of Motor Behaviour 28, 291-298). This relationship was computed from the angular momentum equation applied to the whole body with respect to the CoG using the inverse dynamics approach and force plate recordings, and considering the CoP and CoG oscillations as simple periodic functions. Five subjects were asked to perform voluntary oscillations along medio-lateral and antero-posterior axes, keeping their bodies straight, and without moving their feet. The CoG accelerations measured by the force plate were compared with the CoG accelerations derived from the estimated CoG positions. The average root-mean-square difference between these accelerations was very small, confirming the accuracy of this method. This simplified way to calculate the CoG positions, rarely measured in standing, allows a comparative assessment of motion performance. This method could also be applied to other kinds of movement such as walking.


Subject(s)
Gravitation , Posture/physiology , Acceleration , Adult , Algorithms , Humans , Male , Models, Biological , Movement , Oscillometry , Periodicity , Pressure , Stress, Mechanical
12.
J Arthroplasty ; 8(5): 511-6, 1993 Oct.
Article in English | MEDLINE | ID: mdl-8245996

ABSTRACT

A prospective randomized study was performed on 20 patients undergoing one-stage bilateral knee arthroplasty. One knee was exposed using a standard median parapatellar arthrotomy and the other knee with a subvastus arthrotomy. All patients underwent quantitative strength testing before surgery and at 1 week, 1 month, and 3 months after surgery. The knees were also evaluated for range of motion, and patients, who were blinded as to the approach used, completed questionnaires at each evaluation period as to their preference, if any, regarding knee pain and level of function. There was no difference in the range of motion between knees exposed with the paramedian or subvastus arthrotomy at any time period. The subvastus knees demonstrated significantly greater strength at the 1-week and 1-month intervals, but there was no strength difference at the 3-month interval. There were more lateral releases performed in the paramedium knees, and three minor complications were related to the subvastus approach. Patients who expressed a preference chose the subvastus knee 4:1 over the paramedian knee. The subvastus approach offers a reasonable alternative to the paramedian arthrotomy and preserves greater quadriceps strength in the early postoperative period.


Subject(s)
Knee Prosthesis/methods , Osteoarthritis/surgery , Aged , Female , Follow-Up Studies , Humans , Knee Joint/physiology , Male , Osteoarthritis/epidemiology , Prospective Studies , Range of Motion, Articular/physiology , Time Factors
13.
Behav Neurol ; 4(4): 211-24, 1991.
Article in English | MEDLINE | ID: mdl-24487576

ABSTRACT

Five patients with predominantly dominant cerebral hemisphere lesions due to herpes simplex encephalitis are described. Verbal amnesia was the main deficit but amnesic aphasia sometimes associated with impairment of remote memory also occurred. Semantic and episodic memory deficits were also explored in one case and the role of the right cerebral hemisphere in facilitating recovery of learning is discussed.

14.
Biochim Biophys Acta ; 1040(1): 43-57, 1990 Aug 01.
Article in English | MEDLINE | ID: mdl-2378901

ABSTRACT

The unicellular ciliary protozoan, Stentor coeruleus, exhibits photophobic and phototactic responses to visible light stimuli. The pigment granule contains the photoreceptor chromoproteins (stentorins). Stentorin localized in the pigment granules of the cell serves as the primary photoreceptor for the photophobic and phototactic responses in this organism. An initial characterization of the pigment granules has been described in terms of size, absorbance spectra and ATPase activity. Two forms of the stentorin pigments have been isolated from the pigment granules. Stentorin I has an apparent molecular weight of 68,600 and 52,000 by SDS-PAGE (at 10 and 13% gel, respectively) or 102,000 by steric exclusion HPLC, whereas stentorin II is a larger molecular assembly probably composed of several proteins (mol. wt. greater than 500,000). Stentorin I is composed of at least two heterologous subunits corresponding to apparent mol. wts. of 46,000 (fluorescent, Coomassie blue negative) and 52,000 (fluorescent, Coomassie blue positive) on SDS-PAGE (13% gel). However, these values were found to be strongly dependent on the degree of crosslinking in the acrylamide gel. Stentorin II appears to be the primary photoreceptor whose absorption and fluorescence properties are consistent with the action spectra for the photoresponses of the ciliate to visible light.


Subject(s)
Eukaryota/physiology , Organelles/physiology , Photoreceptor Cells/physiology , Polycyclic Compounds/isolation & purification , Animals , Cell Fractionation , Chromatography, Gel , Chromatography, High Pressure Liquid , Circular Dichroism , Electrophoresis, Polyacrylamide Gel , Eukaryota/ultrastructure , Microscopy, Electron , Microscopy, Electron, Scanning , Molecular Weight , Organelles/ultrastructure , Photoreceptor Cells/ultrastructure , Protein Conformation
16.
Rev Neurol (Paris) ; 146(11): 671-81, 1990.
Article in French | MEDLINE | ID: mdl-2077616

ABSTRACT

Nine cases of post-herpetic encephalitis with predominant involvement of one temporal lobe at CT scan or MRI (6 on the left and 3 on the right sides) were studied 1 to 6 years after onset with repeated language and memory testing. The neuropsychological findings were well correlated with the lateralization and size of the lesions, as previously observed in unilateral temporal lobectomy. Compared with the usual bilateral form, the sequelae were mild, and all the patients, especially those with right hemisphere involvement, resumed a subnormal family life or social activity. In patients with left predominant lesions the anterograde amnesia concerned verbal information, especially logical and abstract, without visual amnesia. In some cases, the episodic verbal amnesia was associated with a semantic deficit which included the knowledge of some words. In one patient the colour, use and mental imagery of some objects corresponding to forgotten words were involved only for some specific groups (natural objects, whereas man-made objects fared better). Testing of verbal memory is proposed to determine the role of the preserved minor hemisphere in learning the context of word presentation, and words with concrete and visual connections which are better recalled than those with abstract or logical link. Disorders of behaviour or mood are usual in the 2 groups of lesions. Thus, herpes encephalitis in these asymmetrical and benign forms in an attractive model to study the role played by the temporal lobe and lateralization in memory.


Subject(s)
Encephalitis/psychology , Functional Laterality/physiology , Herpes Simplex/psychology , Adult , Aged , Amnesia/etiology , Encephalitis/microbiology , Encephalitis/pathology , Female , Herpes Simplex/pathology , Humans , Intelligence Tests , Language Disorders/etiology , Longitudinal Studies , Magnetic Resonance Imaging , Male , Middle Aged , Temporal Lobe/physiopathology , Tomography, X-Ray Computed
17.
Orthop Rev ; 19(1): 58-64, 1990 Jan.
Article in English | MEDLINE | ID: mdl-2105478

ABSTRACT

An unusual case of primary osteomyelitis of the acetabulum caused by Aspergillus flavus in a presumed immunocompetent adult is presented. Review of the literature found 25 additional cases of aspergillar osteomyelitis, which occurred predominantly in hosts with either inborn or acquired immune defects. There were notable differences between the adult and the pediatric cases in causation, clinical presentation, and treatment regimens. In children, the underlying cause was usually severe immunocompromise; among adults, the majority of cases occurred in hosts presumed to be immunocompetent. In all but one case, the children were treated with antifungal chemotherapy alone, whereas the adult patients nearly always received surgical debridement in conjunction with chemotherapy.


Subject(s)
Acetabulum , Aspergillosis/etiology , Immunologic Deficiency Syndromes/complications , Osteomyelitis/etiology , Adult , Aspergillosis/diagnosis , Aspergillosis/therapy , Aspergillus flavus , Female , Humans , Osteomyelitis/diagnosis , Osteomyelitis/therapy
20.
Diagn Cytopathol ; 3(2): 102-7, 1987 Jun.
Article in English | MEDLINE | ID: mdl-3036450

ABSTRACT

Knowledge of the status of the pelvic lymph nodes is important for accurate staging and adequate treatment of patients with genitourinary tract cancer (bladder and prostatic carcinoma, testicular tumors, and uterine carcinoma). A total of 228 consecutive patients underwent preoperative evaluation of the lymph node status by lymphangiography combined with fine-needle aspiration biopsy. A lymphadenectomy was performed in 94 patients. The overall diagnostic accuracy was 93%. There were 5% false-negative results and no false-positive diagnoses. Fine-needle aspiration biopsy is an inexpensive method with which to detect the presence of metastatic lymph nodes visualized by bipedal lymphangiography. It is also a safe and well-tolerated method, with a low morbidity and no mortality. The various cytological features are described as are some possible pitfalls.


Subject(s)
Prostatic Neoplasms/pathology , Testicular Neoplasms/pathology , Urinary Bladder Neoplasms/pathology , Uterine Neoplasms/pathology , Adenocarcinoma/pathology , Biopsy, Needle , Carcinoma, Squamous Cell/pathology , Carcinoma, Transitional Cell/pathology , Dysgerminoma/pathology , Female , Humans , Lymphatic Metastasis , Male , Neoplasm Staging , Neoplasms, Germ Cell and Embryonal/pathology
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