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1.
Phys Rev Lett ; 126(2): 020502, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33512236

RESUMO

The act of observing a quantum object fundamentally perturbs its state, resulting in a random walk toward an eigenstate of the measurement operator. Ideally, the measurement is responsible for all dephasing of the quantum state. In practice, imperfections in the measurement apparatus limit or corrupt the flow of information required for quantum feedback protocols, an effect quantified by the measurement efficiency. Here, we demonstrate the efficient measurement of a superconducting qubit using a nonreciprocal parametric amplifier to directly monitor the microwave field of a readout cavity. By mitigating the losses between the cavity and the amplifier, we achieve a measurement efficiency of (72±4)%. The directionality of the amplifier protects the readout cavity and qubit from excess backaction caused by amplified vacuum fluctuations. In addition to providing tools for further improving the fidelity of strong projective measurement, this work creates a test bed for the experimental study of ideal weak measurements, and it opens the way toward quantum feedback protocols based on weak measurement such as state stabilization or error correction.

2.
Phys Rev Lett ; 123(24): 247701, 2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-31922827

RESUMO

We present a new optomechanical device where the motion of a micromechanical membrane couples to a microwave resonance of a three-dimensional superconducting cavity. With this architecture, we realize ultrastrong parametric coupling, where the coupling not only exceeds the dissipation in the system but also rivals the mechanical frequency itself. In this regime, the optomechanical interaction induces a frequency splitting between the hybridized normal modes that reaches 88% of the bare mechanical frequency, limited by the fundamental parametric instability. The coupling also exceeds the mechanical thermal decoherence rate, enabling new applications in ultrafast quantum state transfer and entanglement generation.

3.
Phys Rev Appl ; 7(2)2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38501125

RESUMO

We report on the design and implementation of a field-programmable Josephson amplifier (FPJA)-a compact and lossless superconducting circuit that can be programmed in situ by a set of microwave drives to perform reciprocal and nonreciprocal frequency conversion and amplification. In this work, we demonstrate four modes of operation: frequency conversion (transmission of -0.5 dB, reflection of -30 dB), circulation (transmission of -0.5 dB, reflection of -30 dB, isolation of 30 dB), phase-preserving amplification (gain > 20 dB, one photon of added noise) and directional phase-preserving amplification (reflection of -10 dB, forward gain of 18 dB, reverse isolation of 8 dB, one photon of added noise). The system exhibits quantitative agreement with the theoretical prediction. Based on a gradiometric superconducting quantum-interference device with Nb/Al-AlOx/Nb Josephson junctions, the FPJA is first-order insensitive to flux noise and can be operated without magnetic shielding at low temperature. Owing to its flexible design and compatibility with existing superconducting fabrication techniques, the FPJA offers a straightforward route toward on-chip integration with superconducting quantum circuits such as qubits and microwave optomechanical systems.

4.
Phys Rev Lett ; 95(8): 081601, 2005 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-16196849

RESUMO

We report on a precision measurement of the parity-violating asymmetry in fixed target electron-electron (Møller) scattering: A(PV) = [-131 +/- 14(stat) +/- 10(syst)] x 10(-9), leading to the determination of the weak mixing angle sin2(thetaW(eff) = 0.2397 +/- 0.0010(stat) +/- 0.0008(syst), evaluated at Q2 = 0.026 GeV2. Combining this result with the measurements of sin2(thetaW(eff) at the Z0 pole, the running of the weak mixing angle is observed with over 6sigma significance. The measurement sets constraints on new physics effects at the TeV scale.

5.
Phys Rev Lett ; 92(18): 181602, 2004 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-15169482

RESUMO

We report a measurement of the parity-violating asymmetry in fixed target electron-electron (Møller) scattering: A(PV)=[-175+/-30(stat)+/-20(syst)] x 10(-9). This first direct observation of parity nonconservation in Møller scattering leads to a measurement of the electron's weak charge at low energy Q(e)(W)=-0.053+/-0.011. This is consistent with the standard model expectation at the current level of precision: sin((2)theta(W)(M(Z))((-)MS)=0.2293+/-0.0024(stat)+/-0.0016(syst)+/-0.0006(theory).

6.
Phys Rev Lett ; 86(24): 5446-9, 2001 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-11415272

RESUMO

New electron scattering measurements have been made that extend data on the (3)He elastic magnetic form factor up to Q(2) = 42.6 fm(-2). These new data test theoretical conjectures regarding non-nucleonic effects in the three-body system. The very small cross sections, as low as 10(-40) cm(2)/sr, required the use of a high-pressure cryogenic gas target and a detector system with excellent background rejection capability. No existing theoretical calculation satisfactorily accounts for all the available data.

9.
Community Ment Health J ; 33(3): 245-50; discussion 251-3, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9211044

RESUMO

Though ubiquitous in community mental health agencies, case management suffers from a lack of consensus regarding its definition, essential components, and appropriate application. Meaningful comparisons of various case management models await such a consensus. Global assessments of case management must be replaced by empirical studies of specific interventions with respect to the needs of specific populations. The authors describe a highly differentiated and prescriptive system of case management involving the application of more than one model of service delivery. Such a diversified and targeted system offers an opportunity to study the technology of case management in a more meaningful manner.


Assuntos
Administração de Caso , Serviços Comunitários de Saúde Mental/organização & administração , Transtornos Mentais/reabilitação , Modelos Organizacionais , Adolescente , Adulto , Idoso , Administração de Caso/economia , Terapia Combinada , Serviços Comunitários de Saúde Mental/economia , Análise Custo-Benefício , Feminino , Humanos , Masculino , Transtornos Mentais/economia , Pessoa de Meia-Idade , Ohio , Equipe de Assistência ao Paciente/economia
10.
Psychiatr Serv ; 47(11): 1251-3, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8916245

RESUMO

The effects of outpatient civil commitment on community tenure and functioning were studied in a group of 20 patients with a history of recurrent hospitalizations, noncompliance with outpatient treatment, and good response to treatment. During the first 12 months of outpatient commitment, patients experienced significant reductions in visits to the psychiatric emergency service, hospital admissions, and lengths of stay compared with the 12 months before commitment. They significantly increased the number of appointments kept with their psychiatrist. It appears that when used judiciously, outpatient civil commitment is a helpful tool in maintaining hospital recidivists in the community.


Assuntos
Transtorno Bipolar/terapia , Internação Compulsória de Doente Mental/legislação & jurisprudência , Serviços Comunitários de Saúde Mental/legislação & jurisprudência , Transtornos Psicóticos/terapia , Esquizofrenia/terapia , Psicologia do Esquizofrênico , Adulto , Transtorno Bipolar/psicologia , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Ohio , Readmissão do Paciente , Transtornos Psicóticos/psicologia , Recusa do Paciente ao Tratamento/legislação & jurisprudência , Recusa do Paciente ao Tratamento/psicologia
12.
Psychiatr Serv ; 47(3): 302-3, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8820557

RESUMO

Clinicians can comply with Ohio state regulations for documenting patients' informed consent for treatment with neuroleptic medication by checking a box in the medical record stating that a periodic discussion of informed consent has occurred and writing a note about the discussion in the narrative record. The authors discuss clinicians' experience with this alternative to the conventional consent form in a large community support agency. Although the approach has been largely successful, implementation has been hindered by some clinicians' incomplete understanding of the informed consent process. Continued training is needed to bring the ideal of informed consent into clinical practice.


Assuntos
Antipsicóticos/uso terapêutico , Regulamentação Governamental , Consentimento Livre e Esclarecido , Transtornos Mentais/tratamento farmacológico , Serviços Comunitários de Saúde Mental/legislação & jurisprudência , Termos de Consentimento , Humanos , Pessoas Mentalmente Doentes , Ohio , Defesa do Paciente , Apoio Social , Estados Unidos
14.
J Environ Qual ; 23(5): 999-1005, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34872224

RESUMO

Farmers in dryland agriculture areas of the Central Great Plains have characteristically practiced alternate crop-fallow to stabilize yields. Large amounts of N released soon after sodbreaking and more recent fertilizer additions may have contributed to N movement below crop root zones. Improved water conservation techniques during fallow periods increases the possibility of NO3 leaching below root zones in modern-day crop-fallow systems. Soil topography and water supply may affect leaching potential. This study was conducted to test hypotheses regarding landscape position effects and potential evapotranspiration on depth of water and NO3 penetration. Three sites in eastern Colorado with equal annual precipitation, but with mean potential evapotranspiration varying from 1000 to 1900 mm yr-1 were evaluated. A soil catena was sampled at each site to test landscape effects. All sites were previously managed under tilled wheat-fallow systems for at least 50 yr. All summit (upland) sites had higher water and NO3 contents below their crop root zones than nearby native prairie sites. Soil water and NO3 content of soil profiles to a depth of 9 m were not related to slope position, but there was an inverse relationship between water and NO3 content of soil profiles and potential evapotranspiration. The total NO3 -N in cultivated profiles below the normal root zone of crops varied from 126 kg ha-1 at the northern site to 47 kg ha-1 at the southern site. Although some NO3 leaching had occurred, it did not appear to be a major problem for any particular landscape position or climatic zone on cultivated soils.

15.
J Anim Sci ; 69(9): 3487-93, 1991 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1938635

RESUMO

Seventy-six primiparous Duroc and Landrace sows from two genetic lines with or without selection for improved sow productivity were used to identify sow traits that affect postweaning gain (positive or negative) and feed intake. Sows lost weight (P less than .01) and consumed less feed (P less than .01) during wk 1 postweaning (37 d) compared with wk 2, 3, and 4. Sows gained more weight during wk 2 and 3 (P less than .01) than during wk 4. Weekly feed consumption was similar during wk 2 and 4 and highest during wk 3 (P less than .05). Sow weight gain postweaning was predicted by sow weaning weight (P less than .01) and adjusted 21-d litter weight (P less than .05) during wk 1, wk 1 to 2, and wk 1 to 4 feeding periods. Feed consumption was best predicted by adjusted litter weaning weight (P less than .01), sow weaning weight (P less than .01), average backfat at farrowing (P less than .01), average backfat change (P less than .05), and adjusted 21-d litter weight (P less than .05). Feed intake was positively correlated (P less than .01; r = .77) and sow weight at breeding, farrowing, and weaning was negatively correlated (P less than .05; r = -.23, -.21, and -.26, respectively) with sow weight gain. Average backfat at weaning was negatively correlated (P less than .05) with gain and feed intake during each period. Adjusted 21-d litter weight and adjusted litter weaning weight were positively correlated with postweaning feed intake (P less than .05; r = .22 and .23, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Ingestão de Alimentos , Suínos/crescimento & desenvolvimento , Desmame , Aumento de Peso , Ração Animal , Animais , Cruzamento , Ingestão de Alimentos/genética , Feminino , Gravidez , Suínos/genética , Aumento de Peso/genética
16.
J Anim Sci ; 69(2): 472-7, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2016176

RESUMO

A total of 457 Duroc, 137 Landrace, 131 Duroc x Landrace, and 110 three-and four-breed crossbred pigs were used to estimate multiplicative adjustment factors. Sixty-one Duroc, 24 Landrace, 18 Duroc x Landrace, and 16 three- and four-breed crossbred litters were weighed every 3 or 4 d from 13 to 30 d of age. Prediction equations for estimating pig weights from birth to 30 d and from 13 to 30 d of age are presented. Multiplicative adjustment factors for adjusting pig or litter weights to a 21-d basis for pigs or litters that are weighed between 13 and 30 d of age for different breeds and crossbred combinations are listed. Breed, litters within breed, and pigs within litter x breed effects adjusted for age at weighing were different (P less than .01). Quadratic regression coefficients of weight on age of pig from 13 to 30 d of age did not differ (P greater than .10) from zero for Landrace and three- and four-breed crossbred pigs but were significant for Duroc and Duroc x Landrace pigs.


Assuntos
Peso Corporal , Suínos/crescimento & desenvolvimento , Animais , Peso ao Nascer , Cruzamento , Cruzamentos Genéticos , Feminino , Análise dos Mínimos Quadrados , Masculino , Análise de Regressão
17.
Domest Anim Endocrinol ; 7(2): 199-206, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2369820

RESUMO

Mammary secretions obtained from four groups of sows at parturition and on days 7, 14 and 21 of lactation were defatted and assayed for total protein and insulin-like growth factor-I (IGF-I). Sows (n = 57) represented two breeds (Landrace and Duroc) and two genetic lines (selected for differences in sow productivity index, SPI) within each breed. Colostrum of Duroc sows was 4-6 fold and 30-60 fold greater in protein (P less than .001) and IGF-I (P less than .001) concentrations, respectively, than the corresponding day 7 milk from these sows. In contrast, the colostrum of Landrace sows was 2-3 fold and 30-50 fold greater in protein (P less than .001) and IGF-I (P less than .001) concentrations, respectively, than the corresponding day 7 milk. The IGF-I content in milk from Duroc sows did not differ among days 7, 14 and 21 of lactation, whereas the IGF-I content of day 7 milk from Landrace sows exceeded those for the corresponding 14 day and 21 day secretion (P less than .05). IGF-I concentration in days 14 and 21 milk was higher in Duroc (P less than .001 respectively) than Landrace sows. No significant differences in total protein or IGF-I content of mammary secretions were observed between the selected and control lines within each breed.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Animais Lactentes/crescimento & desenvolvimento , Fator de Crescimento Insulin-Like I/metabolismo , Lactação/metabolismo , Glândulas Mamárias Animais/metabolismo , Somatomedinas/metabolismo , Suínos/metabolismo , Animais , Cruzamento , Colostro/análise , Feminino , Genótipo , Fator de Crescimento Insulin-Like I/análise , Lactação/genética , Leite/análise , Proteínas do Leite/análise , Gravidez , Suínos/genética , Suínos/crescimento & desenvolvimento
18.
J Behav Ther Exp Psychiatry ; 19(2): 119-26, 1988 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3209696

RESUMO

This study was designed to see whether the high vs low serum level of imipramine influenced the outcome of in vivo exposure therapy on patients with agoraphobia. Thirty-six subjects completed the Hopkins Symptom Checklist-90 one week before treatment and weekly throughout treatment. Both groups demonstrated equal improvement. It was noted that the rate of improvement differed for different symptom subscales: (1) Hostility, Paranoia and Psychotic symptom ratings improved over the first three weeks of treatment, (2) Interpersonal Sensitivity, Anxiety and Depression ratings improved throughout the first seven weeks of treatment and (3) Phobic Anxiety, Somatization and Obsessive Compulsure symptom ratings continued to improve throughout the entire 12 week course of treatment. Responsive vs nonresponsive subjects could be significantly differentiated after one week of treatment on the basis of their responses to the Psychoticism subscale.


Assuntos
Agorafobia/terapia , Terapia Comportamental , Imipramina/administração & dosagem , Transtornos Fóbicos/terapia , Adolescente , Adulto , Idoso , Agorafobia/psicologia , Terapia Combinada , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
19.
J Bacteriol ; 170(1): 442-5, 1988 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2826401

RESUMO

Whereas treatment with many different drugs led to induction of the SOS response in Bacillus subtilis, only inhibitors of DNA gyrase subunit B and, unexpectedly, polyether antibiotics (membrane ionophores) led to relaxation of supercoiled plasmid DNA. However, treatment with DNA gyrase subunit B inhibitors but not with polyethers led to SOS induction. Thus, the presence of underwound supercoiled DNA was not sufficient to induce the SOS response. Possible mechanisms by which polyethers induce relaxation of supercoiled DNA in vivo are discussed.


Assuntos
Bacillus subtilis/genética , Reparo do DNA , DNA Super-Helicoidal/efeitos dos fármacos , Monensin/farmacologia , Novobiocina/farmacologia , Resposta SOS em Genética , Bacillus subtilis/efeitos dos fármacos , DNA Bacteriano/efeitos dos fármacos , Plasmídeos/efeitos dos fármacos , Inibidores da Topoisomerase II
20.
Theriogenology ; 28(1): 15-24, 1987 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16726288

RESUMO

The effects of fenprostalene, cloprostenol sodium and prostaglandin F2 alpha (PGF2alpha) on estrus, conception rate, pregnancy rate, and the interval from Day 1 of the breeding season to calving were studied on 135 purebred Angus cows and heifers. The cows and heifers were randomly allotted within age to the three estrus synchronization treatments and a control group. The calving percentages (for cows and heifers combined) that resulted from artificial insemination (AI) were 32.3, 31.4, 43.6, and 51.1% for the control, fenprostalene, cloprostenol sodium, and PGF2alpha groups, respectively. The calving percentage during the AI period by ages of dam at breeding were 54.2% for yearling heifers, 30.5% for two-year-olds, 47.6% for three-year-olds, and 26.1% for four-year-old or older cows. The percentage of cows and heifers detected in estrus and the percentage that conceived after the first injection for control, fenprostalene, cloprostenol sodium, and PGF2alpha groups were 51.6 and 22.3%, 59.3 and 32.1%, 76.8 and 44.1%, and 66.6 and 50.2%, respectively. The intervals from Day 1 of the breeding season to calving and from Day 1 of the calving season within each treatment to the birth of each calf were control, 285.9 and 23.8 d; fenprostalene, 283.6 and 13.4 d; cloprostenol sodium, 285.5 and 6.5 d; and PGF2alpha, 284.0 and 11.1 d.

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