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1.
Phys Rev Lett ; 116(9): 090501, 2016 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-26991164

RESUMO

Broadband quantum memories hold great promise as multiplexing elements in future photonic quantum information protocols. Alkali-vapor Raman memories combine high-bandwidth storage, on-demand readout, and operation at room temperature without collisional fluorescence noise. However, previous implementations have required large control pulse energies and have suffered from four-wave-mixing noise. Here, we present a Raman memory where the storage interaction is enhanced by a low-finesse birefringent cavity tuned into simultaneous resonance with the signal and control fields, dramatically reducing the energy required to drive the memory. By engineering antiresonance for the anti-Stokes field, we also suppress the four-wave-mixing noise and report the lowest unconditional noise floor yet achieved in a Raman-type warm vapor memory, (15±2)×10^{-3} photons per pulse, with a total efficiency of (9.5±0.5)%.

2.
BJPsych Bull ; 48(2): 78-84, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37395121

RESUMO

BACKGROUND: Training and practice in neuropsychiatry varies across the world. However, little is known about the experiences and opinions of early career psychiatrists (ECPs) across different countries regarding neuropsychiatry. AIMS AND METHOD: To investigate neuropsychiatry training experiences, practices and opinions among ECPs across different countries. An online survey was distributed to ECPs in 35 countries across the world. RESULTS: A total of 522 participants took part in this study. Responses show that neuropsychiatry is integrated to a variable extent in psychiatric training curricula across the world. Most respondents were not aware of the existence of neuropsychiatric training or of neuropsychiatric units. Most agreed that training in neuropsychiatry should be done during or after the psychiatry training period. Lack of interest among specialty societies, lack of time during training, and political and economic reasons are regarded as the main barriers. CLINICAL IMPLICATIONS: These findings call for an improvement in the extent and in the quality of neuropsychiatry training across the world.

3.
Phys Rev Lett ; 110(13): 133601, 2013 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-23581318

RESUMO

Single photons are a vital resource for optical quantum information processing. Efficient and deterministic single photon sources do not yet exist, however. To date, experimental demonstrations of quantum processing primitives have been implemented using nondeterministic sources combined with heralding and/or postselection. Unfortunately, even for eight photons, the data rates are already so low as to make most experiments impracticable. It is well known that quantum memories, capable of storing photons until they are needed, are a potential solution to this "scaling catastrophe." Here, we analyze in detail the benefits of quantum memories for producing multiphoton states, showing how the production rates can be enhanced by many orders of magnitude. We identify the quantity ηB as the most important figure of merit in this connection, where η and B are the efficiency and time-bandwidth product of the memories, respectively.

4.
Phys Rev Lett ; 108(26): 263602, 2012 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-23004977

RESUMO

Quantum memories are vital to the scalability of photonic quantum information processing (PQIP), since the storage of photons enables repeat-until-success strategies. On the other hand, the key element of all PQIP architectures is the beam splitter, which allows us to coherently couple optical modes. Here, we show how to combine these crucial functionalities by addressing a Raman quantum memory with multiple control pulses. The result is a coherent optical storage device with an extremely large time bandwidth product, that functions as an array of dynamically configurable beam splitters, and that can be read out with arbitrarily high efficiency. Networks of such devices would allow fully scalable PQIP, with applications in quantum computation, long distance quantum communications and quantum metrology.

5.
Psychiatry Res ; 272: 730-736, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30832193

RESUMO

The objectives were to evaluate the workplace violence and risk for psychiatric morbidity, as well as their correlates, among health workers in a tertiary healthcare setting in Nigeria. A stratified random sampling technique was used to recruit the health workers. Each participant was administered a socio-demographic questionnaire, the ILO/ICN/WHO/PSI Workplace Violence Questionnaire and the 12- item General Health Questionnaire. A total of 380 health workers were recruited, with a mean age of 36.4 (±7.64) years. The prevalence rates of workplace violence and risk of psychiatric morbidity were 39.9% and 38.5%. Factors with independent associations with workplace violence included young age, female sex and worry about workplace violence while a widowed, separated or divorced marital status and being victim of workplace violence independently increased risk for developing psychiatric morbidity. This study therefore showed that workplace violence is common in the health care setting, and significant proportion of workers are at risk for developing psychiatric morbidity. These observations suggest need for the regular mental health screening of health workers, as well as the need for programmes aimed at preventing workplace violence in this setting.


Assuntos
Pessoal de Saúde/psicologia , Transtornos Mentais/epidemiologia , Transtornos Mentais/psicologia , Atenção Terciária à Saúde , Violência no Trabalho/psicologia , Adulto , Estudos Transversais , Feminino , Pessoal de Saúde/tendências , Humanos , Masculino , Transtornos Mentais/diagnóstico , Pessoa de Meia-Idade , Nigéria/epidemiologia , Prevalência , Inquéritos e Questionários , Atenção Terciária à Saúde/tendências , Local de Trabalho/psicologia , Violência no Trabalho/tendências
6.
J Clin Sleep Med ; 14(8): 1285-1292, 2018 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-30092898

RESUMO

STUDY OBJECTIVES: The objectives of this study were to investigate the psychometric properties of the Sleep Hygiene Index (SHI) and determine its capacity to screen for poor sleep quality in a nonclinical sample of Nigerian university students. METHODS: A total of 348 students appropriately completed the SHI, the Morningness-Eveningness Questionnaire (MEQ), the Pittsburgh Sleep Quality Index (PSQI), and the Epworth Sleepiness Scale (ESS). RESULTS: The internal consistency (Cronbach alpha) of the SHI was .64 and its construct validity was modestly satisfactory. It had a significant negative correlation with the MEQ (r = -.170, P < .001) and positive correlations with global PSQI (r = .289, P < .001) and ESS (r = .219, P < .001) scores. Prior to the factor analysis, our sample was randomly divided into two. In one half of the sample (sample 1), exploratory factor analysis of the SHI items yielded a three-factor model. Confirmatory factor analysis on the other half (sample 2) corroborated this model with satisfactory indices of fitness (c2 = 67.805; df = 55; c2/df = 1.233; P = .115; goodness of fit index = .943; Tucker-Lewis index = .958; incremental fit index = .972; comparative fit index = .970; root mean square error of approximation = .037). A cutoff total score of 16 on the SHI had the best sensitivity (77.0%) and specificity (47.5%) to identify students who were categorized as experiencing poor sleep quality, according to the PSQI (area under the curve = 0.65, 95% confidence interval = 0.59-0.71). CONCLUSIONS: The SHI exhibited satisfactory psychometric properties as a self-rated assessment instrument in the evaluation of sleep hygiene and as a screening instrument for poor sleep quality among Nigerian undergraduate students.


Assuntos
Higiene do Sono/fisiologia , Transtornos do Sono-Vigília/diagnóstico , Estudantes/estatística & dados numéricos , Inquéritos e Questionários/estatística & dados numéricos , Adulto , Estudos Transversais , Análise Fatorial , Feminino , Humanos , Masculino , Nigéria , Psicometria , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Universidades , Adulto Jovem
7.
J Neuroendocrinol ; 28(12)2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27805753

RESUMO

Dehydroepiandrosterone (DHEA) is a testosterone/oestrogen precursor and known modulator of vertebrate aggression. Male song sparrows (Melospiza melodia morphna) show high aggression during breeding and nonbreeding life-history stages when circulating DHEA levels are high, and low aggression during molt when DHEA levels are low. We previously showed that androgen receptor and aromatase mRNA expression are higher during breeding and/or nonbreeding in brain regions associated with reproductive and aggressive behaviour, although the potential role of DHEA in mediating these seasonal changes remained unclear. In the present study, nonbreeding male song sparrows were captured and held in the laboratory under short days (8 : 16 h light/dark cycle) and implanted with s.c. DHEA-filled or empty (control) implants for 14 days. DHEA implants increased aggression in a laboratory-based simulated territorial intrusion. Brains of DHEA-implanted birds showed higher aromatase mRNA expression in the preoptic area (POA) and higher androgen receptor mRNA expression in the periventricular nucleus of the medial striatum (pvMSt) and ventromedial nucleus of the hypothalamus. The DHEA-induced increases in aromatase expression in the POA and androgen receptor expression in the pvMSt are consistent with previously reported seasonal increases in these markers associated with naturally elevated DHEA levels. This suggests that DHEA facilitates seasonal increases in aggression in nonbreeding male song sparrows by up-regulating steroid signalling/synthesis machinery in a brain region-specific fashion.


Assuntos
Agressão/fisiologia , Aromatase/metabolismo , Proteínas Aviárias/fisiologia , Encéfalo/fisiologia , Desidroepiandrosterona/fisiologia , Receptores Androgênicos/metabolismo , Pardais/fisiologia , Animais , Masculino , RNA Mensageiro/metabolismo
8.
Neuropharmacology ; 29(2): 161-5, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2158635

RESUMO

The recent preparation of the enantiomers of 11-OH-delta 8-tetrahydrocannabinol-dimethylheptyl (THC-DMH), recrystallized to absolute enantiomeric purity, has made it possible to examine the requirement for stereospecificity for the interaction of this component with the cannabinoid receptor, defined by the binding of [3H]CP-55,940 and the adenylate cyclase enzyme. The enantiomer (-)11-OH-delta 8-THC-DMH exhibited a fully efficacious and potent (IC50 = 1.8 nM) inhibition of the accumulation of cAMP in intact N18TG2 cells. The (-)enantiomer was as efficacious and potent (Kinh = 7.2 nM) as desacetyllevonantradol in inhibiting adenylate cyclase activity in membrane preparations. The (-)enantiomer was able to compete fully for the specific binding of [3H]CP-55,940 to membranes from the brain of the rat in homologous displacement studies (Ki = 234 pM). The potency ratios exhibited by the (-) to (+)enantiomers of 11-OH-delta 8-THC-DMH exceeded 1000 for each of these activities.


Assuntos
Inibidores de Adenilil Ciclases , Dronabinol/análogos & derivados , Dronabinol/farmacologia , Receptores de Droga/metabolismo , Adenilil Ciclases/metabolismo , Animais , Células Cultivadas , AMP Cíclico/metabolismo , Cicloexanóis/metabolismo , Dronabinol/metabolismo , Técnicas In Vitro , Masculino , Ratos , Ratos Endogâmicos , Receptores de Canabinoides
9.
Popul Trends ; (83): 5-16, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8729791

RESUMO

Monitoring migration trends and patterns is not a straightforward task given the absence of a compulsory United Kingdom-wide system for recording domestic changes of address. Nevertheless, data extracted from the available sources offer a valuable insight into the diverse and complex phenomenon of migration. This article examines international and internal migration phenomenon of migration in the 1980s and 1990s, and looks at the geographical impact of the two in combination on the population of the United Kingdom. This is the third article in the Population Review series. Earlier articles on: (1) Structure and distribution of the population and (2) Are we healthier? appeared in Population Trends issues no. 81 and no. 82 respectively.


Assuntos
Emigração e Imigração/estatística & dados numéricos , Dinâmica Populacional , Adolescente , Adulto , Idoso , Coeficiente de Natalidade , Criança , Pré-Escolar , Etnicidade/estatística & dados numéricos , Feminino , Humanos , Lactente , Mortalidade Infantil , Masculino , Pessoa de Meia-Idade , Densidade Demográfica , Reino Unido/epidemiologia
10.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);68(1): 252-256, jan.-fev. 2016. ilus, tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-874992

RESUMO

Acupuncture derives from traditional Chinese medicine, which aims to restore homeostasis. The action mechanism of this technique involves stimulation of certain points on the skin by inserting a needle. The aim of this study was to evaluate the influence of stimulation of acupoints C7 and PC6 on the heart rate variability, heart rate and heart rhythm in healthy dogs. 30 male and female adult dogs were used, with no breed restriction. The animals were analyzed at two different times in weekly intervals. Firstly were applied needles in the true acupoints, and on the second time we applied needles in false acupoints. Previously to the acupuncture an ECG with 2 minutes of recorder was performed, and after an insertion of needles the electrocardiographic recording was maintained during the 30 minutes of acupuncture. Results showed no significant difference between the HR when comparing true and false acupoints (p = 0.890). For heart rate variability a small difference was observed between the groups (p = 0.0051), however, when comparing the baseline with 15 and 25 minutes of monitoring in the false acupoint group, no significant results were found when compared with true acupoint. In conclusion, it is suggested that the stimulation of acupoints C-7 and PC-6 in healthy dogs does not promote change in sympathovagal balance, specifically on the heart rate variability, heart rate and heart rhythm on healthy dogs.(AU)


Assuntos
Animais , Cães , Pontos de Acupuntura , Terapia por Acupuntura/veterinária , Frequência Cardíaca , Sistema Nervoso Parassimpático , Sistema Nervoso Simpático
11.
Science ; 334(6060): 1253-6, 2011 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-22144620

RESUMO

Quantum entanglement in the motion of macroscopic solid bodies has implications both for quantum technologies and foundational studies of the boundary between the quantum and classical worlds. Entanglement is usually fragile in room-temperature solids, owing to strong interactions both internally and with the noisy environment. We generated motional entanglement between vibrational states of two spatially separated, millimeter-sized diamonds at room temperature. By measuring strong nonclassical correlations between Raman-scattered photons, we showed that the quantum state of the diamonds has positive concurrence with 98% probability. Our results show that entanglement can persist in the classical context of moving macroscopic solids in ambient conditions.

12.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);67(4): 1025-1032, July-Aug. 2015. tab, ilus
Artigo em Português | LILACS | ID: lil-759237

RESUMO

A eletrocardiografia computadorizada é mais precisa e prática quando comparada à convencional e por essa razão vem ganhando espaço na rotina clínica. No entanto os valores de referência devem diferir para os dois métodos. O objetivo desse trabalho foi analisar e comparar o exame eletrocardiográfico computadorizado com o exame obtido pelo método convencional em equinos. O estudo demonstrou diferenças na amplitude da onda P (P<0,0001) com valor médio de 0,21 mV para o método convencional e 0,17 mV para o computadorizado; duração do intervalo PR (p=0,0005), tendo o valor médio de 260,49 ms para o método convencional e 242,37 ms para o informatizado e duração do complexo QRS (p=0,0003), sendo a média de valores para o método convencional de 75,61ms e 84,83 ms para o computadorizado. Essas diferenças devem ser levadas em consideração com o intuito de evitar equívocos na interpretação da eletrocardiografia na espécie equina.


Computerized electrocardiography has been gaining space in clinic routines because it is more practical and precise when compared to the conventional method. However, their reference values may differ from each other. The aim of this paper was to analyze and compare computerized and conventional electrocardiography in horses. Differences were observed between P wave amplitude (P<0001) with a mean of 0.21mV in the conventional method and 0.17mV in the computerized method, PR interval duration (p=0.0005) with a mean of 260.49 ms and 242.37 ms in the conventional and computerized methods respectively, and QRS complex duration (p=0.0003) with a mean of 75.61 ms in the conventional method and 84.83 ms in the computerized method. These differences should be taken into consideration in order to avoid misunderstandings in the interpretation of the electrocardiogram in equine species.


Assuntos
Animais , Eletrocardiografia , Cavalos , Informática Médica/métodos , Informática Médica/tendências , Exames Médicos/análise
14.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);66(1): 310-314, fev. 2014. ilus
Artigo em Português | LILACS | ID: lil-704039

RESUMO

This paper describes the occurrence of cor triatriatum sinister, a rare cardiac malformation in dogs, associated with pulmonary edema and pulmonary hypertension in a 5-year-old Poodle female with history of acute dyspnea and cyanosis. The animal presented acute respiratory failure, heart failure with low cardiac output, progressing to acute tubular necrosis and death. The diagnosis was made posmortem due to the clinical instability of the dog. This malformation was diagnosed by the subdivision of the left atrium into two compartments separated by an abnormal fibromuscular membrane, absence of structural abnormalities of the mitral valve and thickening of pulmonary artery tunica media associated with renal tubular degeneration. The occurrence of cor triatriatum in dogs is most common in the right atrium, defined as cor triatriatum dexter. Additionally, pulmonary arterial hypertension associated with this malformation is described only in humans with this heart defect.


Assuntos
Animais , Cães , Artéria Pulmonar/anatomia & histologia , Cardiopatias Congênitas/diagnóstico , Hipertensão/patologia , Cães/classificação
15.
Town Ctry Plann ; 66(3): 77-9, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12322158

RESUMO

"Urban deconcentration is the most dominant and consistent feature of population movement in Britain nowadays.... The scale of urban out-migration varies over time, some types of people and places are more fully represented in the urban exodus than others, and the net figures hide the fact that quite sizeable numbers of people move in the opposite direction.... The research was based largely in 1991 Population Census data on people who changed address within Great Britain during the year preceding Census night, focusing mainly on migration between local authority districts grouped according to their degree of 'urbanness' and their distance from the main metropolitan centres."


Assuntos
Emigração e Imigração , Densidade Demográfica , Dinâmica Populacional , População Urbana , Demografia , Países Desenvolvidos , Europa (Continente) , Geografia , População , Reino Unido
16.
Geogr Rev (Oxf) ; 7(1): 10-5, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12288500

RESUMO

"In this article the provisional 1991 estimates [from the 1991 U.K. census] are used to highlight the unevenness of population distribution around the country. They are then compared with the 1981 data in order to identify the principal changes of the past decade."


Assuntos
Demografia , Dinâmica Populacional , Países Desenvolvidos , Europa (Continente) , Geografia , População , Reino Unido
17.
Town Ctry Plann ; : 305-7, 1983 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12314601

RESUMO

The authors introduce a new map of Britain, which is based on the city region concept and designed specifically to present data from the 1981 census. The primary purposes of this article are "to describe the main problems and distortions which result from using current administrative areas, outline the key features of the new way of defining British cities, and demonstrate the value of the new geographical framework with some basic statistics on city size and population trends."


Assuntos
Demografia , Geografia , Mapas como Assunto , Dinâmica Populacional , Terminologia como Assunto , População Urbana , Países Desenvolvidos , Europa (Continente) , População , Características da População , Estatística como Assunto , Reino Unido
18.
J Exp Zool ; 206(3): 451-6, 1978 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-712350

RESUMO

Normal adult mouse tibialis anterior muscles were perfused continuously with 3H-thymidine for nine days. Quantitation of the satellite cell population in these muscles reveals that not only is the frequency of satellite cell nuclei low, but that those present are mitotically quiescent.


Assuntos
Músculos/citologia , Envelhecimento , Animais , Autorradiografia , Camundongos , Microscopia Eletrônica , Mitose , Músculos/metabolismo
19.
Agents Actions ; 21(3-4): 244-6, 1987 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2961217

RESUMO

Type II collagen-induced arthritis (CIA) and mice was used as a model to evaluate the effect of etodolac on the arthritic and immunological parameters of the experimental disease. In a preventative protocol, a significant reduction was observed in the number of joints progressing to ankylosis. At high doses (16 mg/kg/day) a significant delay in the onset of arthritis was also observed. No significant effect was seen on the progression of the disease when etodolac was administered in established CIA. No consistent variations were observed in the anti-type II collagen response or other immunological parameters of the experimental arthritis.


Assuntos
Acetatos/farmacologia , Artrite Reumatoide/prevenção & controle , Animais , Anti-Inflamatórios não Esteroides , Artrite Reumatoide/induzido quimicamente , Colágeno , Etodolac , Camundongos , Camundongos Endogâmicos DBA
20.
J Virol ; 73(7): 5637-45, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10364313

RESUMO

A recombinant fusion protein (BBG2Na) comprising the central conserved domain of the respiratory syncytial virus subgroup A (RSV-A) (Long) G protein (residues 130 to 230) and an albumin binding domain of streptococcal protein G was shown previously to protect mouse upper (URT) and lower (LRT) respiratory tracts against intranasal RSV challenge (U. F. Power, H. Plotnicky-Gilquin, T. Huss, A. Robert, M. Trudel, S. Stahl, M. Uhlén, T. N. Nguyen, and H. Binz, Virology 230:155-166, 1997). Panels of monoclonal antibodies (MAbs) and synthetic peptides were generated to facilitate dissection of the structural elements of this domain implicated in protective efficacy. All MAbs recognized native RSV-A antigens, and five linear B-cell epitopes were identified; these mapped to residues 152 to 163, 165 to 172, 171 to 187 (two overlapping epitopes), and 196 to 204, thereby covering the highly conserved cysteine noose domain. Antibody passive-transfer and peptide immunization studies revealed that all epitopes were implicated in protection of the LRT, but not likely the URT, against RSV-A challenge. Pepscan analyses of anti-RSV-A and anti-BBG2Na murine polyclonal sera revealed lower-level epitope usage within the central conserved region in the former, suggesting diminished immunogenicity of the implicated epitopes in the context of the whole virus. However, Pepscan analyses of RSV-seropositive human sera revealed that all of the murine B-cell protective epitopes (protectopes) that mapped to the central conserved domain were recognized in man. Should these murine protectopes also be implicated in human LRT protection, their clustering around the highly conserved cysteine noose region will have important implications for the development of RSV vaccines.


Assuntos
Antígenos Virais/imunologia , Epitopos de Linfócito B/imunologia , Proteína HN , Infecções por Vírus Respiratório Sincicial/imunologia , Vírus Sincicial Respiratório Humano/imunologia , Proteínas Virais/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Sítios de Ligação , Modelos Animais de Doenças , Mapeamento de Epitopos , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Peptídeos/síntese química , Peptídeos/imunologia , Proteínas Recombinantes de Fusão/imunologia , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Proteínas do Envelope Viral
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