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1.
Phys Rev Lett ; 127(14): 140402, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34652182

RESUMO

Compared to light interferometers, the flux in cold-atom interferometers is low and the associated shot noise is large. Sensitivities beyond these limitations require the preparation of entangled atoms in different momentum modes. Here, we demonstrate a source of entangled atoms that is compatible with state-of-the-art interferometers. Entanglement is transferred from the spin degree of freedom of a Bose-Einstein condensate to well-separated momentum modes, witnessed by a squeezing parameter of -3.1(8) dB. Entanglement-enhanced atom interferometers promise unprecedented sensitivities for quantum gradiometers or gravitational wave detectors.

2.
Phys Rev Lett ; 117(20): 203003, 2016 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-27886486

RESUMO

We demonstrate a quantum gravimeter by combining the advantages of an atom chip for the generation, delta-kick collimation, and coherent manipulation of freely falling Bose-Einstein condensates (BECs) with an innovative launch mechanism based on Bloch oscillations and double Bragg diffraction. Our high-contrast BEC interferometer realizes tens of milliseconds of free fall in a volume as little as a one centimeter cube and paves the way for measurements with sub-µGal accuracies in miniaturized, robust devices.

3.
Phys Rev Lett ; 116(17): 173601, 2016 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-27176520

RESUMO

We employ light-induced double Bragg diffraction of delta-kick collimated Bose-Einstein condensates to create three symmetric Mach-Zehnder interferometers. They rely on (i) first-order, (ii) two successive first-order, and (iii) second-order processes which demonstrate the scalability of the corresponding momentum transfer. With respect to devices based on conventional Bragg scattering, these symmetric interferometers double the scale factor and feature a better suppression of noise and systematic uncertainties intrinsic to the diffraction process. Moreover, we utilize these interferometers as tiltmeters for monitoring their inclination with respect to gravity.

4.
Phys Rev Lett ; 114(6): 063002, 2015 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-25723216

RESUMO

We realize beam splitters and mirrors for atom waves by employing a sequence of light pulses rather than individual ones. In this way we can tailor atom interferometers with improved sensitivity and accuracy. We demonstrate our method of composite pulses by creating a symmetric matter-wave interferometer which combines the advantages of conventional Bragg- and Raman-type concepts. This feature leads to an interferometer with a high immunity to technical noise allowing us to devise a large-area Sagnac gyroscope yielding a phase shift of 6.5 rad due to the Earth's rotation. With this device we achieve a rotation rate precision of 120 nrad s(-1) Hz(-1/2) and determine the Earth's rotation rate with a relative uncertainty of 1.2%.

5.
J Intellect Disabil Res ; 55(2): 199-209, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20546095

RESUMO

BACKGROUND: Physical distress resulting from medical problems has been found to cause increased behaviour problems in patients with intellectual disabilities (ID). Despite this fact, little has been documented on the medical problems of individuals with ID admitted for inpatient psychiatric care. We conducted an exploratory investigation based on a retrospective chart review of the medical problems and medications for 198 people with ID who had been admitted to a specialised inpatient psychiatric unit. Most patients were referred for admission because of aggressive, disruptive and self-injurious behaviours. The average length of stay was 17.6 days. METHODS: We tallied the total number of medical problems and medications listed in the patients' discharge summaries. Because longer stays are disruptive, costly and associated with greater overall impairment, we examined the relationship between length of stay and frequency of discharge medical diagnoses. We also assessed whether or not the number of psychoactive medications correlated with the number of medical diagnoses. The effects of other demographic and diagnostic variables on rates of medical diagnoses and medications were also evaluated, including gender, age group (16-25, 26-45, 46-60, >60), level of ID (mild, moderate or severe ID) and diagnosis of an autism spectrum disorder or Down syndrome (DS). RESULTS: Inpatients with a higher number of medical diagnoses had longer lengths of stay (Spearman r = +0.32, P < 0.0001). There was a significant correlation between number of psychoactive medications and number of medical problems (Spearman r = +0.32, P < 0.0001). The most frequent medical comorbidity was constipation, reported in 60% of the inpatients (n = 118), while gastro-esophageal reflux disease was identified in 38% (n = 75). Older inpatients had an increased number of medical problems, as might be expected, but a diagnosis of an autism spectrum disorder, gender and level of ID had no detectible effect on rates of either medical diagnoses or medications. There were only 13 inpatients with DS; in this modest sample, it was found that they had higher rates of osteoarthritis, cardiac problems, hearing loss, hypothyroidism and sleep apnoea than peers without DS, as is consistent with previous findings on overrepresented conditions in this trisomy. CONCLUSIONS: In the present study, individuals with ID admitted for inpatient psychiatric care exhibited high rates of medical problems, and these were associated with duration of inpatient stay. Based on these findings, further investigation of the effects of medical problems on behaviour among individuals with ID admitted for inpatient psychiatric care is warranted.


Assuntos
Nível de Saúde , Deficiência Intelectual/complicações , Tempo de Internação/estatística & dados numéricos , Pessoas com Deficiência Mental/psicologia , Instituições Residenciais/estatística & dados numéricos , Adolescente , Adulto , Idoso , Estudos de Coortes , Constipação Intestinal/complicações , Feminino , Refluxo Gastroesofágico/complicações , Hospitais Psiquiátricos , Humanos , Deficiência Intelectual/fisiopatologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Avaliação das Necessidades , Projetos Piloto , Adulto Jovem
6.
Opt Lett ; 34(15): 2321-3, 2009 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-19649084

RESUMO

We observe coherent, cw, 455 nm blue-beam production via frequency upconversion in cesium vapor. Two IR lasers induce strong double excitation in a heated cesium vapor cell, allowing the atoms to undergo a double cascade and produce a coherent, collimated, blue beam copropagating with the two IR pump lasers.

7.
Biol Psychiatry ; 50(4): 231-7, 2001 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-11522256

RESUMO

BACKGROUND: Exposure to extremely stressful events can lead to Posttraumatic stress disorder (PTSD). Due to the complexity of PTSD, animal models have been designed and advanced to address the role of psychosocial stressors in the etiology; however, the apparent role of genetics in susceptibility to PTSD-like behaviors in animals remains unexplored. METHODS: An animal model of congenital learned helpless (cLH) behavior has been used to study the effects of genetic disposition as a risk factor for the development of PTSD-like behaviors. Animals were monitored for changes in pain tolerance, spatial memory and hypothalamic-pituitary-adrenal functioning after re-exposure to intermittent stress in the presence and absence of situational cues. RESULTS: Exposure to stress resulted in an increase in pain tolerance in the cLH animals. In the spatial memory test 80% of the cLH animals manifested a decrease in performance after exposure to stress. These animals also had a blunted poststress corticosterone response. CONCLUSIONS: The genetic learned helpless animal model exhibited physiologic symptoms of analgesia, cognitive deficits and hyporesponsivity of the hypothalamic-pituitary-adrenal axis similar to those observed in human subjects with PTSD. It is proposed that the cLH model may be a valuable tool for exploring the role of genetic predisposition in the etiology of PTSD.


Assuntos
Modelos Animais de Doenças , Transtornos de Estresse Pós-Traumáticos/genética , Animais , Encéfalo/metabolismo , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/genética , Corticosterona/metabolismo , Predisposição Genética para Doença , Desamparo Aprendido , Ratos , Transtornos de Estresse Pós-Traumáticos/metabolismo
8.
Environ Sci Technol ; 35(6): 1090-6, 2001 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-11347919

RESUMO

Metal partitioning in ferrihydrite suspensions may reach equilibrium only after a long reaction time. To determine key factors controlling the kinetics, we measured Cu and Pb uptake as a function of ferrihydrite morphology, reaction temperature, metal competition, and fulvic acid concentration over a period of 2 months. X-ray microscopy, which was used to probe ferrihydrite morphology in suspension, showed that drying irreversibly converted the gellike structure of fresh precipitate into dense aggregates. These dense aggregates sorbed Cu and Pb much slower than the gel. Temperature had a more pronounced effect on the kinetics of metal uptake by ferrihydrite gel than by dense ferrihydrite. Independently of treatment and time, Cu and Pb were bound to the ferrihydrite surface byformation of edge-sharing inner-sphere sorption complexes as confirmed by X-ray absorption fine-structure (XAFS) spectroscopy. This invariable binding mechanism, together with the observed effects of morphology and temperature, are in line with surface diffusion limiting the slow sorption process. The quantification of diffusion-limited surface sites in soils and sediments and the subsequent estimation of the effect of reaction time and temperature will be a challenge for properly predicting the fate of metals in the environment.


Assuntos
Cobre/química , Ferritinas/química , Chumbo/química , Poluentes do Solo , Adsorção , Benzopiranos/química , Compostos Férricos , Previsões , Cinética , Modelos Teóricos , Temperatura
11.
J Synchrotron Radiat ; 7(Pt 2): 110-2, 2000 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-16609182

RESUMO

A specimen chamber is described for soft X-ray spectromicroscopy of hydrated specimens and solutions. Applications include imaging and carbon edge spectroscopy of hydrated clay/polymer suspensions.

12.
J Am Psychoanal Assoc ; 41(3): 627-51, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8354840

RESUMO

Despite universal agreement about the importance of transference, there is no single, comprehensive, generally accepted explanation for the place transference occupies in clinical psychoanalytic theory. In this presentation, I trace the origins of some major trends prominent in theoretical controversy to their antecedents. Some seminal contributions which introduced important issues into the evolving theory of transference are highlighted; this is followed by a brief outline of the ideas of a representative sample of current theorists. This comparison of the appearance of fundamental evolutionary modifications of transference theory with present-day differences in theoretical emphasis leads to the identification of four persistent themes: (1) the nature of the influence of the patient's relationship with the analyst in the analytic experience, (2) how to account for the analyst's subjectivity and its role in the analytic process, (3) what weight to assign to the interpersonal dimension of the transference, and (4) differences among theoretical perspectives as reflected in the precise content of transference interpretations. Difficulties in the path of comparative evaluation of differences in theoretical accounts of the transference and its handling are noted. A few reasons for my adherence to the theory I prefer are mentioned solely for the purpose of underlining areas of controversy that require serious attention and further clarification.


Assuntos
Terapia Psicanalítica , Transferência Psicológica , Contratransferência , Mecanismos de Defesa , Teoria Freudiana , Humanos , Apego ao Objeto , Desenvolvimento da Personalidade , Interpretação Psicanalítica , Autoimagem
13.
J Clin Invest ; 88(3): 898-903, 1991 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1885776

RESUMO

TSH secretion is decreased by both T4 and T3. This negative feedback control of TSH secretion has been correlated with an increase in pituitary nuclear T3 content, and it is not clear whether T4 exerts its effect directly on the thyrotroph or after its deiodination to T3. However, levels of the pituitary enzyme catalyzing T4 to T3 conversion, 5'D-II, are decreased in the presence of an increased amount of T4. Thus, it is unclear why the thyrotroph would have a mechanism for modulating the production of T3, if T3 is, in fact, the sole bioactive signal providing negative feedback inhibition. To examine this apparent paradox, we administered EMD 21388, a compound which inhibits the binding of T4 to transthyretin resulting in a rapid increase in circulating free T4 levels, to rats pretreated with radiolabeled T4 and T3. We observed increases in pituitary and liver T4 content of greater than 150%, without increases in the respective tissue T3 contents. The EMD 21388-treated rats also exhibited a 25% decrease in pituitary 5'D-II activity (103.8 +/- 15.8 fmol 125I released.mg protein-1.h-1, vs. control, 137.4 +/- 15.9, mean +/- SE), as did rats treated with sodium salicylate, another compound that inhibits T4-TTR binding (100.8 +/- 7.1). TSH levels significantly decreased 2 h after the administration of EMD 21388. These data demonstrate that despite a T4-mediated decrease in pituitary 5'D-II activity, an increase in T4 independently decreases TSH secretion.


Assuntos
Iodeto Peroxidase/análise , Hipófise/enzimologia , Tireotropina/metabolismo , Tiroxina/fisiologia , Animais , Flavonoides/sangue , Flavonoides/farmacologia , Masculino , Hipófise/química , Pré-Albumina/metabolismo , Ratos , Ratos Endogâmicos , Salicilatos/farmacologia , Ácido Salicílico , Tireotropina/sangue , Tiroxina/sangue , Tri-Iodotironina/análise
14.
Psychoanal Q ; 59(4): 532-49, 1990 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2267269

RESUMO

One motive for regarding psychoanalysis as a "process," and for attempting to define its exact nature, is to enable analysts to clarify their criteria for distinguishing authentic psychoanalysis from other therapies that resemble it or are derived from it. In the present climate of theoretical pluralism, any list of defining qualities that could win wide acceptance would of necessity be cast in terms of such general quality as to limit its utility as a precise template. Another motive for holding on to the "process" concept arises from the unpredictable nature of analytic progress in even the most satisfactory cases.


Assuntos
Teoria Psicanalítica , Terapia Psicanalítica/métodos , Mecanismos de Defesa , Humanos , Desenvolvimento da Personalidade , Relações Médico-Paciente , Interpretação Psicanalítica , Transferência Psicológica , Inconsciente Psicológico
15.
Acta Endocrinol (Copenh) ; 123(1): 79-83, 1990 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2389627

RESUMO

Thalidomide, a derivative of glutamic acid, has immunosuppressive effects and suppresses graft-vs-host disease in the rat and following bone marrow transplantation in man. It is effectively used in the treatment of erythema nodosum leprosum and has a potential therapeutic effect in a variety of autoimmune diseases. In view of these observations, we evaluated the effect of thalidomide on the incidence of spontaneous and iodine-induced lymphocytic thyroiditis and spontaneous insulin dependent diabetes mellitus in the BB/Wor rat. Thalidomide did not suppress the incidence of lymphocytic thyroiditis and serum anti-thyroglobulin antibodies or affect the serum concentrations of T4, T3 and TSH in this rat model. Thalidomide also did not affect the incidence of insulin dependent diabetes mellitus. In contrast to preliminary studies in man and rat demonstrating efficacy in the therapy of autoimmune diseases, thalidomide did not prevent or suppress autoimmune lymphocytic thyroiditis or insulin-dependent diabetes mellitus in the BB/Wor rat.


Assuntos
Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Tipo 1/complicações , Iodo/toxicidade , Talidomida/farmacologia , Tireoidite Autoimune/induzido quimicamente , Animais , Feminino , Masculino , Ratos , Ratos Endogâmicos BB , Tireoidite Autoimune/complicações , Tireotropina/sangue , Tiroxina/sangue , Tri-Iodotironina/sangue
16.
Immunopharmacology ; 19(3): 163-8, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2394579

RESUMO

Previous studies have suggested that ciamexone, a 2-cyan-aziridine derivative, is a selective immunomodulatory agent with potential therapeutic application in a variety of autoimmune diseases. In the present study, the effects of ciamexone on autoimmune lymphocytic thyroiditis and diabetes mellitus were studied in the BB rat. The data suggest that, in this animal model, ciamexone does not affect the frequency of autoimmune diabetes or lymphocytic thyroiditis nor does it affect the serum TSH or T4 concentrations.


Assuntos
Aziridinas/farmacologia , Diabetes Mellitus Tipo 1/prevenção & controle , Tireoidite Autoimune/prevenção & controle , Adjuvantes Imunológicos/farmacologia , Animais , Avaliação Pré-Clínica de Medicamentos , Feminino , Masculino , Ratos , Ratos Endogâmicos BB , Tireoidite Autoimune/sangue , Tireotropina/sangue , Tiroxina/sangue , Fatores de Tempo
17.
J Clin Endocrinol Metab ; 70(4): 903-7, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2318947

RESUMO

To examine the effects of hypothyroidism on androstenedione (A) and estrone (E1) metabolism, we infused eight women with [3H]androstenedione and [14C]estrone when they were hypothyroid and again when they were euthyroid after levo-T4 administration. MCRs and conversion ratios were measured using concentrations of radioactivity in the blood pools of A and E1. Peripheral aromatization was measured from the concentrations of radioactivity in the E1 glucuronide pool in the urine. After the women were euthyroid, the MCR of A had increased in seven of eight, the MCR of E1 increased in all eight, and peripheral aromatization had decreased in seven of eight. These findings indicate that hypothyroidism results in a decrease in the MCRs of A and E1 and, in most subjects, an increase in peripheral aromatization of A to E1.


Assuntos
Androstenodiona/farmacocinética , Estrona/farmacocinética , Hipotireoidismo/sangue , Adulto , Feminino , Seguimentos , Humanos , Hipotireoidismo/tratamento farmacológico , Infusões Intravenosas , Cinética , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Tireotropina/sangue , Tiroxina/uso terapêutico , Tri-Iodotironina/sangue
18.
JAMA ; 263(11): 1526-8, 1990 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-2308184

RESUMO

Amiodarone hydrochloride, an iodine-rich drug used in the treatment of tachyarrhythmias, is responsible for the development of thyrotoxicosis in approximately 10% of patients who reside in areas of moderate iodine deficiency. Treatment of amiodarone-induced thyrotoxicosis is difficult since the drug has a prolonged half-life, cardiac decompensation due to underlying heart disease occurs often, and discontinuation of amiodarone therapy may not be possible. We report a patient with severe thyrotoxicosis who received amiodarone for 34 months. Prolonged treatment with methimazole, potassium perchlorate, iopanoic acid, and dexamethasone was unsuccessful in controlling the hyperthyroid state. A near-total thyroidectomy resulted in rapid amelioration of thyrotoxicosis. Since surgery results in rapid control of thyrotoxicosis and permits continued therapy with amiodarone, we suggest that near-total thyroidectomy warrants consideration as definitive treatment for resistant amiodarone-induced thyrotoxicosis.


Assuntos
Amiodarona/efeitos adversos , Tireoidectomia , Tireotoxicose/induzido quimicamente , Humanos , Masculino , Pessoa de Meia-Idade , Testes de Função Tireóidea , Tireotoxicose/fisiopatologia , Tireotoxicose/cirurgia
19.
J Am Psychoanal Assoc ; 38(1): 61-73, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2348047

RESUMO

Although the existence of unconscious fantasies is an empirical assumption, in the clinical situation unconscious fantasies are treated as if they have a concrete existence. Unconscious fantasies form intermediate links in causal chains of which clinical observations constitute one end, and the components of unconscious conflicts, the other. Like all clinical material, fantasies may be affected by actual experiences; they may also be revised, layered, and can function to alter and disguise other fantasies as well as provide gratification. From a technical standpoint, it is most important to analyze their constituents and to adduce their primary purposes in the clinical situation of the moment. The nature of the evidence that identifies the presence of particular unconscious fantasies is discussed. Although a single analytic session is presented by way of illustration, I am convinced that the analyst's entire understanding of the patient inevitably channels his or her interpretive focus on the associational material of each analytic hour.


Assuntos
Fantasia , Teoria Psicanalítica , Terapia Psicanalítica , Inconsciente Psicológico , Adulto , Feminino , Teoria Freudiana , Humanos , Relações Mãe-Filho , Interpretação Psicanalítica , Transferência Psicológica
20.
Psychoanal Q ; 58(3): 374-95, 1989 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2672063

RESUMO

This paper examines the evolution of the concept of counter-transference, with particular emphasis on its relationship to psychoanalytic technique. Freud's original idea that countertransference means unconscious interference with an analyst's ability to understand patients has been broadened during the past forty years: current usage often includes all of the emotional reactions of the analyst at work. Some factors that have contributed to this shift are the introduction of the structural hypothesis, the impact of Kleinian and interpersonal schools on the theory of technique, the effect of analysts' experience in working with more severely ill patients, and the diffuse consequences of certain recent cultural and intellectual trends. The benefits as well as some potential disadvantages in this shift toward a more inclusive conceptualization are discussed.


Assuntos
Contratransferência , Transtornos Mentais/terapia , Teoria Psicanalítica , Terapia Psicanalítica/métodos , Teoria Freudiana , Humanos , Transtornos Mentais/psicologia
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