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1.
Opt Express ; 31(3): 3504-3519, 2023 Jan 30.
Article in English | MEDLINE | ID: mdl-36785342

ABSTRACT

Nowadays, atom-based quantum sensors are leaving the laboratory towards field applications requiring compact and robust laser systems. Here we describe the realization of a compact laser system for atomic gravimetry. Starting with a single diode laser operating at 780 nm and adding only one fiber electro-optical modulator, one acousto-optical modulator and one laser amplifier we produce laser beams at all the frequencies required for a Rb-87 atomic gravimeter. Furthermore, we demonstrate that an atomic fountain configuration can also be implemented with our laser system. The modulated system reported here represents a substantial advance in the simplification of the laser source for transportable atom-based quantum sensors that can be adapted to other sensors such as atomic clocks, accelerometers, gyroscopes or magnetometers with minor modifications.

3.
Phys Rev E ; 103(4-1): 043004, 2021 Apr.
Article in English | MEDLINE | ID: mdl-34005940

ABSTRACT

The counterintuitive fact that wave chaos appears in the bending spectrum of free rectangular thin plates is presented. After extensive numerical simulations, varying the ratio between the length of its sides, it is shown that (i) frequency levels belonging to different symmetry classes cross each other and (ii) for levels within the same symmetry sector, only avoided crossings appear. The consequence of anticrossings is studied by calculating the distribution of the ratio of consecutive level spacings for each symmetry class. The resulting ratio distributions disagree with the expected Poissonian result. They are then compared with some well-known transition distributions between Poisson and the Gaussian orthogonal random matrix ensemble. It is found that the distribution of the ratio of consecutive level spacings agrees with the prediction of the Rosenzweig-Porter model. Also, the normal-mode vibration amplitudes are found experimentally on aluminum plates, before and after an avoided crossing for symmetrical-symmetrical, symmetrical-antisymmetrical, and antisymmetrical-symmetrical classes. The measured modes show an excellent agreement with our numerical predictions. The expected Poissonian distribution is recovered for the simply supported rectangular plate.

4.
Hand Surg Rehabil ; 39(6): 564-567, 2020 12.
Article in English | MEDLINE | ID: mdl-32652251

ABSTRACT

The radial nerve is a commonly injured upper extremity peripheral nerve. The inability to extend the wrist results in a loss of hand function and dexterity that affects patients' ability to perform their activities of daily living. There is no strong evidence to support a particular splint design for improving dexterity. This cohort study compared whether a static or dynamic splint can improve hand dexterity when assessed with the 9-hole peg test (9-HPT) after radial nerve injury. Thirty-four subjects with radial nerve palsy participated in the study. The test was repeated three times for each subject, first without the splint, and then while wearing the control static wrist splint, and finally while wearing the dynamic splint. The 9-HPT was used as the outcome measure. The 9-HPT times were 36.4±4.8seconds without a wrist splint and improved when using the static and the dynamic splints to 33.5±4.5seconds (P<0.01) and 25.7±3.5seconds (P<0.01) respectively. The use of a dynamic splint after radial nerve palsy can provide the patient with greater manual dexterity when compared to using no splint or a static splint.


Subject(s)
Motor Skills/physiology , Peripheral Nerve Injuries/rehabilitation , Radial Nerve/injuries , Radial Neuropathy/rehabilitation , Splints , Adult , Cohort Studies , Equipment Design , Female , Humans , Male , Peripheral Nerve Injuries/physiopathology , Radial Neuropathy/physiopathology
5.
Osteoarthritis Cartilage ; 28(5): 572-580, 2020 05.
Article in English | MEDLINE | ID: mdl-32156623

ABSTRACT

OBJECTIVE: Several reports in the literature have identified an association between cortisol levels and the presence of chronic pain in conditions such as rheumatoid arthritis, low back pain or whiplash. In contrast, few have examined the association of cortisol and pain in people with osteoarthritis (OA). The purpose of this systematic review was to verify the association between cortisol and pain in the OA population. DESIGN: The databases MEDLINE, CINAHL, EMBASE were searched systematically for human studies written in English up to December 2018. Two researchers screened titles and abstracts against predefined inclusion criteria; a third resolved discrepancies. Articles were included if they measured the cortisol levels in adults with pain in the OA population. Methodological quality was assessed using Methodological Index for non-randomized Studies (MINORS) score. RESULTS: Seven studies reporting on 415 patients were included in this review. The MINORS scale yielded mean scores of 8.6 of 16 and 17.5 of 24, for the cohort and case-control studies respectively. In general, the studies were of poor quality. A discrepancy of noteworthy associations between cortisol level comparison and pain was found. CONCLUSIONS: This study shows that there is a discrepancy in the relationship between cortisol and pain dependent on how and when cortisol is measured. Evidence from three low-quality studies suggest increased cortisol levels in patients with pain but the conclusions have a high risk of bias. It was not possible to make a quantitative analysis comparing the relationship between cortisol and pain in the OA population.


Subject(s)
Chronic Pain/metabolism , Hydrocortisone/metabolism , Osteoarthritis/metabolism , Humans
6.
Opt Lett ; 44(17): 4428-4431, 2019 Sep 01.
Article in English | MEDLINE | ID: mdl-31465420

ABSTRACT

In this Letter, we present a spatially homogeneous field inside of a ring cavity that was created by combining two transverse modes generated by a single laser through modulation. The interference term between the two modes averages out because of the frequency difference that exists between them, eliminating the need for interferometric control of their relative phase. The use of a ring cavity allows for a large waist for the flat-top profile, big enough to cover the atoms in an atomic trap. The cavity is mechanically and thermally isolated, and the laser light is locked to the cavity using the Pound-Drever-Hall technique. The flat-top profile technique reported here fulfills the vanishing curvature criterion at the center of the profile.

9.
Sci Rep ; 6: 25157, 2016 04 28.
Article in English | MEDLINE | ID: mdl-27121226

ABSTRACT

Coherent transport phenomena are difficult to observe due to several sources of decoherence. For instance, in the electronic transport through quantum devices the thermal smearing and dephasing, the latter induced by inelastic scattering by phonons or impurities, destroy phase coherence. In other wave systems, the temperature and dephasing may not destroy the coherence and can then be used to observe the underlying wave behaviour of the coherent phenomena. Here, we observe coherent transmission of mechanical waves through a two-dimensional elastic Sinai billiard with two waveguides. The flexural-wave transmission, performed by non-contact means, shows the quantization when a new mode becomes open. These measurements agree with the theoretical predictions of the simplest model highlighting the universal character of the transmission fluctuations.

11.
Eur J Neurosci ; 39(6): 999-1008, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24772465

ABSTRACT

Factors underlying individual vulnerability to develop alcoholism are largely unknown. In humans, the risk for alcoholism is associated with elevated cue reactivity. Recent evidence suggests that in animal models, reactivity to reward-paired cues is predictive of addictive behaviors. To model cue reactivity in mice, we used a Pavlovian approach (PA) paradigm in which mice were trained to associate a cue with delivery of a food reinforcer. We then investigated the relationship between PA status with habitual and compulsive-like ethanol seeking. After training mice to respond for 10% ethanol, habitual behavior was investigated using both an outcome devaluation paradigm, in which ethanol was devalued via association with lithium chloride-induced malaise, and a contingency degradation paradigm in which the relationship between action and outcome was disrupted. Compulsive-like behavior was investigated in a modified conditioned place preference paradigm in which footshock was paired with the reward-paired chamber. PA was found to be predictive of habitual and compulsive-like ethanol seeking. Additionally, innate risk status was related to epigenetic changes in the gene encoding the requisite subunit of the 5HT3 receptor, Htr3a, as well as 5HT3A protein expression in the amygdala. We then used pharmacological tools to demonstrate that risk status determines the ability of a 5HT3 antagonist to reduce compulsive ethanol seeking. These data indicate that risk status can be identified prior to any alcohol exposure by assessment of cue reactivity, and further that this endophenotype may be predictive of response to pharmacological treatment for components of alcoholism.


Subject(s)
Behavior, Addictive , Drug-Seeking Behavior , Epigenesis, Genetic , Receptors, Serotonin, 5-HT3/metabolism , Amygdala/drug effects , Amygdala/metabolism , Amygdala/physiology , Animals , Conditioning, Classical , Ethanol/pharmacology , Male , Mice , Receptors, Serotonin, 5-HT3/genetics , Reward
12.
Phys Rev Lett ; 111(17): 170405, 2013 Oct 25.
Article in English | MEDLINE | ID: mdl-24206466

ABSTRACT

We present the first experimental microwave realization of the one-dimensional Dirac oscillator, a paradigm in exactly solvable relativistic systems. The experiment relies on a relation of the Dirac oscillator to a corresponding tight-binding system. This tight-binding system is implemented as a microwave system by a chain of coupled dielectric disks, where the coupling is evanescent and can be adjusted appropriately. The resonances of the finite microwave system yield the spectrum of the one-dimensional Dirac oscillator with and without a mass term. The flexibility of the experimental setup allows the implementation of other one-dimensional Dirac-type equations.

13.
Med Lav ; 104(5): 380-92, 2013.
Article in English | MEDLINE | ID: mdl-24180086

ABSTRACT

BACKGROUND: Low Back Pain (LBP) is a very common disorder in hospital workers. Several studies examined the efficacy of multimodal interventions for health care providers suffering from LBP; nevertheless their results did not appear to be consistent. OBJECTIVE: The aim of the study was to determine the effect of a multimodal group programme (MGP) on pain and disability in a sample of hospital workers with persistent LBP. METHODS: A prospective cohort study was conducted to compare baseline measurements with changes over an eight-month period. The study focused on 109 workers suffering from persistent LBP with or without radiating pain. 62 nurses and 47 blue collars not involved in health care. The MGP consisted of six group sessions including supervised exercises, an at-home programme and ergonomic advice. The primary outcome measurement was the level of disability recorded with the Roland & Morris Disability Questionnaire, while the secondary outcome measurement was the evaluation of lumbar physical discomfort with the Visual Analogue Scale. Data were analyzed using the Multiple Imputation method for dropouts. RESULTS: At the short-term follow-up participants showed a statistically significant reduction (from baseline) of all outcome measurements, particularly for the nurses group. Moreover, about a third of the subjects showed clinically significant improvement. No significant reduction in pain and disability (from baseline) was observed at the mid-term follow-up in either group. CONCLUSIONS: An MGP dedicated to hospital workers seems to be partially useful only for short-term follow-up, particularly for health care providers.


Subject(s)
Cognitive Behavioral Therapy , Exercise Therapy , Low Back Pain/therapy , Personnel, Hospital , Psychotherapy, Group/methods , Adult , Combined Modality Therapy , Disability Evaluation , Ergonomics , Female , Follow-Up Studies , Humans , Low Back Pain/epidemiology , Low Back Pain/prevention & control , Low Back Pain/rehabilitation , Male , Middle Aged , Nursing Staff , Occupational Diseases/epidemiology , Occupational Diseases/prevention & control , Occupational Diseases/rehabilitation , Occupational Diseases/therapy , Pain Measurement , Prevalence , Program Evaluation , Prospective Studies , Retrospective Studies , Severity of Illness Index , Treatment Outcome , Weight Lifting
14.
Eur J Phys Rehabil Med ; 49(4): 597-609, 2013 Aug.
Article in English | MEDLINE | ID: mdl-24084418

ABSTRACT

BACKGROUND: This article is the first in a series presenting the strongest published evidence for physical and rehabilitation medicine (PRM) to date coming from the Cochrane Collaboration. The intent of the series is to stimulate ideas for reviews and research in neglected areas of PRM. AIM: To systematically review the rehabilitation contents of the Cochrane Collaboration on disabilities due to spinal disorders or pain syndromes in adults. METHODS: The Cochrane Database of Systematic Reviews was searched at the end of June 2013 for articles relevant for PRM about disabilities resulting from spinal disorders or pain syndromes in adults. Retrieved papers were classified according to the PRM approach: active therapies, which require active participation by patients to achieve treatment goals, and passive treatments, which rely on the application of external forces. The quality of the reviews was checked against the AMSTAR checklist. RESULTS: Reviews on spinal disorders or pain syndromes were found in the Cochrane Back Group (CBG) and in the Pain, Palliative and Supportive Care Group (CPPSCG). Thirty-eight (42.8%) of 89 Cochrane reviews in the CBG and 7 (2.4%) of 293 Cochrane reviews in the CPPSCG were included. All were of high quality (range, 8-11 points out of 11 on the AMSTAR checklist). The contents of the reviews are given in detail. CONCLUSION: This review presents an overview of the current evidence for PRM in the treatment of disabilities due to spinal disorders or pain syndromes in adults. Within PRM there is ample space for research in the Cochrane Collaboration and for producing original studies (randomized controlled trials [RCTs]). CLINICAL REHABILITATION IMPACT: To apply evidence-based clinical practice, clinicians must be familiar with the current best evidence.


Subject(s)
Evidence-Based Medicine , Pain Management/standards , Physical Therapy Modalities/standards , Physical and Rehabilitation Medicine/standards , Self-Help Devices , Spinal Diseases/rehabilitation , Spinal Injuries/rehabilitation , Adult , Fibromyalgia/rehabilitation , Humans , Pain/etiology , Pain/rehabilitation , Pain Management/methods , Patient Education as Topic , Physical and Rehabilitation Medicine/methods , Review Literature as Topic , Syndrome
15.
J Hazard Mater ; 172(2-3): 1617-22, 2009 Dec 30.
Article in English | MEDLINE | ID: mdl-19747771

ABSTRACT

A systematic study of the effect of design and operation conditions of an electrochemical reactor on the treatment time for arsenic (As) electro-removal from underground water (GW) was carried out to analyse the energy and electrode consumption. The effects of four factors--current density, interelectrode distance, electrode area-volume ratio, and liquid motion driving mode--were evaluated. The response variables were the energy and the electrode consumption and the treatment time to reduce the GW residual As concentration to 10 microg L(-1), which is the maximum contaminant level (MCL) established by the World Health Organization (WHO) in drinking water. The results obtained in this study showed that the factor that had the greatest effect on most of the response variables was the liquid motion driving mode. The best residence time was 20s, which favoured low energy consumption (58.78 Wh m(-3)) and low electrode material loss (9.59 g m(-3)).


Subject(s)
Arsenic/isolation & purification , Electrocoagulation/methods , Water Pollutants/isolation & purification , Water Purification/methods , Water Supply/standards , Electricity , Electrodes , Fresh Water/chemistry , World Health Organization
16.
J Ky Med Assoc ; 99(7): 285-7, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11468869

ABSTRACT

The Q-T interval by electrocardiogram may be prolonged as a congenital or acquired condition. The congenital form, long QT syndrome (LQTS) is an electrical disorder associated with a high mortality rate. However, in newborns, electrolyte abnormalities are one of the most common causes of a long Q-T interval. We describe a newborn with a prolonged Q-T interval (0.55 secs) and abnormal T waves resembling LQTS. In this case, the patient had an electrolyte disturbance which was effectively treated. This case emphasizes the importance of investigating and distinguishing between the congenital and acquired forms of prolonged Q-T intervals.


Subject(s)
Hypocalcemia/complications , Hypocalcemia/diagnosis , Long QT Syndrome/etiology , Magnesium Deficiency/complications , Magnesium Deficiency/diagnosis , Calcium/blood , Diagnosis, Differential , Electrocardiography , Humans , Hypocalcemia/blood , Hypocalcemia/drug therapy , Infant, Newborn , Magnesium/blood , Magnesium Deficiency/blood , Magnesium Deficiency/drug therapy , Male
17.
Arch. venez. farmacol. ter ; 20(1): 80-83, 2001. graf
Article in Spanish | LILACS | ID: lil-340962

ABSTRACT

Se realizó un estudio abierto, no controlado, multicéntrico, realizado con intención de tratar, en 60 pacientes con dorsolumbalgia mecánica, en el cual evaluó la efectividad y seguridad de nimesulide 100 mg dos veces al día, administrado durante 15 días. El tratamiento produjo un alivio significativo en los escores de dolor entre el día de inicio del tratamiento y los 5 días, con un alivio adicional importante entre los días 5 y 10, sin alivios adicionales para el día 15. El tiempo medio para la desaparición total del dolor fue de 8,5 días. La limitación funcional fue evaluada el día 0 y el día 15, obteniéndose una mejoría significativa desde el punto de vista estadístico. Se reportaron efectos adversos en 4 de los pacientes, de los cuales sólo uno ameritó la suspensión del tratamiento


Subject(s)
Humans , Male , Female , Anti-Inflammatory Agents, Non-Steroidal , Back , Low Back Pain/therapy , Venezuela
18.
Circulation ; 97(2): 142-6, 1998 Jan 20.
Article in English | MEDLINE | ID: mdl-9445165

ABSTRACT

BACKGROUND: Long-QT syndrome (LQTS) is a disorder of ventricular repolarization characterized by a prolonged QT interval, syncope, seizures, and sudden death. Recently, three forms of LQTS have been shown to result from mutations in potassium or sodium ion channel genes: KVLQT1 for LQT1, HERG for LQT2, and SCN5A for LQT3. IsK, an apparent potassium channel subunit encoded by KCNE1 on chromosome 21, regulates both KVLQT1 and HERG. This relationship makes KCNE1 a likely candidate gene, because mutations of these genes are known to cause both the autosomal dominant Romano-Ward and recessive Jervell and Lange-Nielsen (JLN) forms of LQTS. METHODS AND RESULTS: We screened 84 unrelated patients with Romano-Ward and 4 with JLN for possible mutations in KCNE1. We identified one homozygous mutation in a JLN patient that results in the nonconservative substitution of Asn for Asp at amino acid 76. The patient is congenitally deaf-mute, with recurrent syncopal events and a greatly prolonged QTc interval. The proband's mother and half-sister are both heterozygous for this mutation. Remarkably, both these family members have prolonged QTc intervals and would have been classified as Romano-Ward patients if not for the proband's diagnosis of JLN. This mutation was not identified in more than 100 control individuals. CONCLUSIONS: These data provide strong evidence that KCNE1 mutations represent a fifth LQTS locus (LQT5). Further functional analysis, as well as the identification of more LQTS patients with KCNE1 mutations, will be important to confirm the role of IsK in LQTS.


Subject(s)
Long QT Syndrome/genetics , Mutation , Child , DNA Primers/chemistry , Electrocardiography , Female , Gene Amplification , Humans , Long QT Syndrome/complications , Long QT Syndrome/physiopathology , Syncope/etiology
19.
Ann Thorac Surg ; 63(3): 835-7, 1997 Mar.
Article in English | MEDLINE | ID: mdl-9066413

ABSTRACT

Although progress has been made in treating hypoplastic left heart syndrome, improvements in perioperative care may further decrease mortality. We present a case in which continuous monitoring of systemic venous oxygen saturation allowed stabilization and successful management of a critically ill infant. Systemic venous oxygen saturation may provide a more accurate representation of a child's clinical status, allowing more rapid intervention and better outcomes.


Subject(s)
Hypoplastic Left Heart Syndrome/blood , Oxygen/blood , Blood Vessel Prosthesis , Combined Modality Therapy , Female , Humans , Hypoplastic Left Heart Syndrome/diagnosis , Hypoplastic Left Heart Syndrome/therapy , Infant, Newborn , Monitoring, Physiologic/methods , Palliative Care
20.
Pediatr Cardiol ; 16(2): 82-4, 1995.
Article in English | MEDLINE | ID: mdl-7784241

ABSTRACT

Antiarrhythmic agents may induce ventricular arrhythmias. Whereas amiodarone is a reported cause of ventricular fibrillation in children, there are no reported cases in infants. We observed two patients with atrial flutter and congestive heart failure who were treated with amiodarone. Both had anatomic heart defects and had failed conventional therapy. Ventricular fibrillation occurred 3 and 12 days after the initial dose. Q-T interval, electrolytes, digoxin level, and amiodarone level (one patient) were normal. Amiodarone may provoke life-threatening ventricular tachyarrhythmias during the convalescent period. Consideration should be given to monitoring in a hospital setting for at least 2 weeks following initiation of amiodarone therapy.


Subject(s)
Amiodarone/adverse effects , Atrial Flutter/drug therapy , Heart Failure/drug therapy , Ventricular Fibrillation/chemically induced , Amiodarone/administration & dosage , Amiodarone/pharmacokinetics , Atrial Flutter/blood , Electrocardiography, Ambulatory/drug effects , Female , Heart Failure/blood , Humans , Infant , Male , Resuscitation , Risk Factors , Ventricular Fibrillation/blood , Ventricular Fibrillation/diagnosis
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