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Learning physical properties of high-dimensional states is crucial for developing quantum technologies but usually consumes an exceedingly large number of samples which are difficult to afford in practice. In this Letter, we use the methodology of quantum metrology to tackle this difficulty, proposing a strategy built upon entangled measurements for dramatically reducing sample complexity. The strategy, whose characteristic feature is symmetrization of observables, is powered by the exploration of symmetric structures of states which are ubiquitous in physics. It is provably optimal under some natural assumption, efficiently implementable in a variety of contexts, and capable of being incorporated into existing methods as a basic building block. We apply the strategy to different scenarios motivated by experiments, demonstrating exponential reductions in sample complexity.
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The geometric phase is a fundamental quantity characterizing the holonomic feature of quantum systems. It is well known that the evolution operator of a quantum system undergoing a cyclic evolution can be simply written as the product of holonomic and dynamical components for the three special cases concerning the Berry phase, adiabatic non-Abelian geometric phase, and nonadiabatic Abelian geometric phase. However, for the most general case concerning the nonadiabatic non-Abelian geometric phase, how to separate the evolution operator into holonomic and dynamical components is a long-standing open problem. In this Letter, we solve this open problem. We show that the evolution operator of a quantum system can always be separated into the product of holonomy and dynamic operators. Based on it, we further derive a matrix representation of this separation formula for cyclic evolution, and give a necessary and sufficient condition for a general evolution being purely holonomic. Our finding is not only of theoretical interest itself, but also of vital importance for the application of quantum holonomy. It unifies the representations of all four types of evolution concerning the adiabatic/nonadiabatic Abelian/non-Abelian geometric phase, and provides a general approach to realizing purely holonomic evolution.
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Quantifying coherence has received increasing attention, and considerable work has been directed towards finding coherence measures. While various coherence measures have been proposed in theory, an important issue following is how to estimate these coherence measures in experiments. This is a challenging task, since the state of a system is often unknown in practical applications and the accessible measurements in a real experiment are typically limited. In this Letter, we put forward an approach to estimate coherence measures of an unknown state from any limited experimental data available. Our approach is not only applicable to coherence measures but can be extended to other resource measures.
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Quantum computation that combines the coherence stabilization virtues of decoherence-free subspaces and the fault tolerance of geometric holonomic control is of great practical importance. Some schemes of adiabatic holonomic quantum computation in decoherence-free subspaces have been proposed in the past few years. However, nonadiabatic holonomic quantum computation in decoherence-free subspaces, which avoids a long run-time requirement but with all the robust advantages, remains an open problem. Here, we demonstrate how to realize nonadiabatic holonomic quantum computation in decoherence-free subspaces. By using only three neighboring physical qubits undergoing collective dephasing to encode one logical qubit, we realize a universal set of quantum gates.
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The quantitative condition has been widely used in the practical applications of the adiabatic theorem. However, it had never been proved to be sufficient or necessary before. It was only recently found that the quantitative condition is insufficient, but whether it is necessary remains unresolved. In this Letter, we prove that the quantitative condition is necessary in guaranteeing the validity of the adiabatic approximation.
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BACKGROUND AND PURPOSE: Despite evidence from clinical and population studies, the aim of the present study was to suggest that multiple factors contribute to periodic breathing (PB). However, little information has been focused on episodes of tracheobronchial infections (TBI) preceding PB onset. METHODS: Thirty subjects with acute stroke who had PB and 41 subjects with acute stroke that of a sex- and age-matched control group without PB were retrospectively evaluated. Stroke location, extent of stroke (demonstrated on CT or MRI), and characteristics of TBI before PB were assessed. PB diagnosis was carried out using a portable device and a pulse oximeter. Risk factors for patients with PB were compared with those without PB by univariate and multivariate analysis. RESULTS: Twenty-four TBI in 30 patients with PB and 11 TBI in 41 patients with non-PB were diagnosed. There was no significant difference in age, sex, body mass index, stroke type, stroke location, or underlying diseases between the two groups (P > 0.05). There was a significant difference in snoring, first recurrent stroke, Glasgow Coma Scale, congestive heart failure, TBI, and inflammatory responses between the PB and non-PB group (P < 0.05). Multiple logistic regression analyses showed a difference in the prevalence of snoring (OR = 10.813, CI = 2.131-54.866, P < 0.01), TBI (OR = 5.313, CI = 1.241-22.740, P < 0.05), and inflammatory responses (OR = 7.315, CI = 1.253-43.123, P < 0.05) between the two groups. CONCLUSIONS: In addition to snoring, TBI and inflammatory responses are the two independent predictors for PB in patients with acute stroke. Clinicians should be encouraged to systematically evaluate TBI and inflammatory responses before PB in patients with acute stroke.
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Infecciones del Sistema Respiratorio/epidemiología , Accidente Cerebrovascular/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Bronquios/microbiología , Respiración de Cheyne-Stokes/diagnóstico , Respiración de Cheyne-Stokes/epidemiología , Respiración de Cheyne-Stokes/microbiología , Estudios de Cohortes , Comorbilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infecciones del Sistema Respiratorio/diagnóstico , Infecciones del Sistema Respiratorio/microbiología , Estudios Retrospectivos , Accidente Cerebrovascular/complicaciones , Tráquea/microbiologíaRESUMEN
OBJECTIVE: Hepatocellular carcinoma (HCC) is a primary malignancy of liver. Nowadays HCC is one of the most common and aggressive malignancies worldwide. This study shows the aberrant up-regulation or down-regulation of miR-370correlates with the development and prognosis of different human malignancies including HCC. MATERIALS AND METHODS: The HCC cell lines were used as model cell lines and the anti-tumor effect of miR-370 in vitro were examined. The level of miR-370 in HCC cells was determined by qRT-PCR and restored in GC cells by using miR-370 mimic. Moreover, the target gene of miR-370 was then identified. RESULTS: The expression of miR-370 in HCC cell lines was significantly lower than that in the other human liver cells. The miR-370 acted as a tumor suppressor in HCC. Moreover, it showed that miR-370 exerted anti-tumor effect by targeting PIM1 directly, a serine/threonine-specific kinase involved in the development and progression of HCC. CONCLUSIONS: miR-370 acted as the tumor suppressor in HCC and was a potential therapeutic target for HCC treatment.
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Carcinoma Hepatocelular/genética , Genes Supresores de Tumor , Neoplasias Hepáticas/genética , MicroARNs/genética , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Proliferación Celular , Regulación hacia Abajo , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Hepáticas/patología , Proteínas Proto-Oncogénicas c-pim-1/genética , Proteínas Proto-Oncogénicas c-pim-1/metabolismoRESUMEN
This study aimed to investigate the association between ADAM metallopeptidase domain 33 (ADAM33) gene polymorphisms and the risk of childhood asthma. The relevant studies about the relationship between ADAM33 gene polymorphisms and childhood asthma were searched from electronic databases and the deadline of retrieval was May 2016. The single nucleotide polymorphisms (SNPs) of ADAM33 (rs511898, rs2280092, rs3918396, rs528557, rs2853209, rs44707, rs2280091 and rs2280089) were analyzed based on several models including the allele, codominant, recessive and dominant models. The results showed that the ADAM33 rs2280091 polymorphism in all four genetic models was associated with an increased risk of childhood asthma. Positive associations were also found between the polymorphisms rs2280090, rs2787094, rs44707 and rs528557 and childhood asthma in some genetic models. This meta-analysis suggested that ADAM33 polymorphisms rs2280091, rs2280090, rs2787094, rs44707 and rs528557 were significantly associated with a high risk of childhood asthma.
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Proteínas ADAM/genética , Asma/genética , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple , Alelos , Niño , Humanos , Factores de RiesgoRESUMEN
A practical quantum computer must be capable of performing high fidelity quantum gates on a set of quantum bits (qubits). In the presence of noise, the realization of such gates poses daunting challenges. Geometric phases, which possess intrinsic noise-tolerant features, hold the promise for performing robust quantum computation. In particular, quantum holonomies, i.e., non-Abelian geometric phases, naturally lead to universal quantum computation due to their non-commutativity. Although quantum gates based on adiabatic holonomies have already been proposed, the slow evolution eventually compromises qubit coherence and computational power. Here, we propose a general approach to speed up an implementation of adiabatic holonomic gates by using transitionless driving techniques and show how such a universal set of fast geometric quantum gates in a superconducting circuit architecture can be obtained in an all-geometric approach. Compared with standard non-adiabatic holonomic quantum computation, the holonomies obtained in our approach tends asymptotically to those of the adiabatic approach in the long run-time limit and thus might open up a new horizon for realizing a practical quantum computer.
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A comprehensive model is developed to describe the swelling/dissolution behaviors and drug release from hydrophilic matrices. The major thrust of this model is to employ an important physical property of the polymer, the polymer disentanglement concentration, rho p,dis, the polymer concentration below which polymer chains detach off the gelled matrix. For (hydroxypropyl)methylcellulose (HPMC) in water, we estimate that rho p,dis scales with HPMC molecular weight, M, as rho p,dis varies M-0.8. Further, matrix dissolution is considered similar to the dissolution of an object immersed in a fluid. As a result, a diffusion layer separating the matrix from the bulk solution is incorporated into the transport regime. An anisotropic expansion model is also introduced to account for the anisotropic expansion of the matrix where surface area in the radial direction dominates over the axial surface area. The model predicts that the overall tablet size and the characteristic swelling time correlate with rho p,dis qualitatively. Two scaling laws are established for fractional polymer (mp(t)/mp(infinity)) and drug (md(t)/md(infinity)) released as mp(t)/mp(infinity) varies M-1.05 and md(t)/md(infinity) varies M-0.24, consistent with the limiting polymer molecular weight effect on drug release. Model predictions for polymer and drug release agree well with observations, within 15% error. Evolution of water concentration profiles and the detailed structure of a swollen matrix are discussed.
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Benzodiazepinas/química , Preparaciones de Acción Retardada/química , Metilcelulosa/análogos & derivados , Química Farmacéutica , Derivados de la Hipromelosa , Matemática , Metilcelulosa/química , Modelos Químicos , Peso MolecularRESUMEN
A new contraceptive option, medroxyprogesterone acetate (MPA) and estradiol cypionate (E2C) (MPA/E2C, Lunelle Monthly Contraceptive Injection), will soon be available for women in the US. This article reports the results of a US trial that assessed the effects of body weight and injection site on the pharmacokinetics of MPA, the progestin mediating contraceptive efficacy. This assessment was part of a nonrandomized, open-label, multicenter US study in healthy women receiving a monthly injection of MPA/E2C for 60 weeks. A total of 77 women (aged 18-47 years) at four centers participated in the pharmacokinetics assessment during the sixth or the seventh injection. For determination of serum MPA concentration-time profiles, blood samples were collected before the sixth and seventh injections (day 0) and on days 3, 7, 14, 21, and 28 after the sixth and seventh monthly administrations. For effects of injection site, MPA pharmacokinetics were compared at injection sites of the arm, hip, and leg. The pharmacokinetics of MPA, determined at the sixth and seventh injection, were not significantly affected by injection sites. The mean area under the curve (AUC0-28), however, was different between the arm and the leg injection sites; the difference was < 20%. More important, the average MPA trough concentrations (Cmin) at the fifth and sixth monthly injections were similar (range 0.42-0.51 ng/mL) for the three injection sites and well above the threshold levels of 0.10-0.20 ng/mL required to suppress ovulation. For effects of body mass index (BMI) on pharmacokinetics, women were stratified into three groups: thin/normal (BMI 18-28, n = 48), obese (BMI 29-38, n = 23), and highly obese (BMI > 38, n = 6). There were no significant differences in the pharmacokinetics of MPA among the three BMI categories. The only significant difference (p = 0.0387) was the AUC0-28 between BMI 18-28 and BMI 29-38. Because of the small sample size in the highly obese group, a reanalysis was performed by pooling subjects of the obese and highly obese groups. Results of the pooled statistical analysis remained the same. In summary, these results suggest that minor differences observed in the MPA pharmacokinetics--whether due to injection site or body weight or both--have no impact on the contraceptive efficacy of MPA/E2C, as trough concentrations (Cmin) are well above the threshold levels required to suppress ovulation. No dose adjustment is necessary based on body weight or injection site.
PIP: A nonrandomized, open-label, multicenter study assessed the effects of body weight and injection site on the pharmacokinetics of medroxyprogesterone acetate (MPA) and its progestin medicating contraceptive efficacy among 77 healthy, fertile women aged 18-47 years. For determination of serum MPA concentration-time profiles, blood samples were collected before the 6th and 7th injections (day 0) and on days 3, 7, 14, 21, and 28 after the 6th and 7th monthly administrations. For injection site effects, MPA pharmacokinetics were compared at the injection sites of the arm, hip, and leg; there was no significant finding. For effects of body mass, no significant differences were noticed in the pharmacokinetics of MPA among the 3 body mass indices (thin/normal, obese, highly obese). However, a difference (p = 0.0387) was found between normal and obese women (20%). The findings suggest that minor differences observed in MPA pharmacokinetics have no impact on the contraceptive efficacy of MPA/E2C, may it be due to injection sites or body weight, since trough concentrations are well above the threshold levels required to suppress ovulation.
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Peso Corporal , Anticonceptivos Femeninos/farmacocinética , Estradiol/análogos & derivados , Inyecciones Intramusculares , Acetato de Medroxiprogesterona/farmacocinética , Adulto , Brazo , Índice de Masa Corporal , Anticonceptivos Femeninos/administración & dosificación , Estradiol/administración & dosificación , Estradiol/farmacocinética , Femenino , Cadera , Humanos , Cinética , Acetato de Medroxiprogesterona/administración & dosificación , MusloRESUMEN
We have examined the regression effect and its magnitude under the Gaussian distributional assumption. The impact and implication of regression to the mean on the analysis of medical investigations was discussed. For simplicity, we called the approach adjusting for the regression effect a two-stage procedure and noted its relationship to the analysis of covariance model for comparing treatment groups. We also proposed to examine the correlation structure among repeated measurements in the absence of any external interventions through a model more realistic than the one assuming equal correlations. The proposed structure led us to investigate ways to reduce or eliminate regression effect via study designs when patient selection is inevitable. Two examples were given to help illustrate the discussion in this paper.
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Biometría , Análisis de Regresión , Análisis de Varianza , Antihipertensivos/uso terapéutico , Presión Sanguínea/efectos de los fármacos , Colesterol/sangre , Ensayos Clínicos como Asunto/estadística & datos numéricos , Humanos , Hiperlipidemias/sangre , Hiperlipidemias/tratamiento farmacológico , Hipertensión/tratamiento farmacológico , Hipertensión/fisiopatología , Hipolipemiantes/uso terapéutico , Modelos Estadísticos , Ensayos Clínicos Controlados Aleatorios como Asunto/estadística & datos numéricos , Proyectos de InvestigaciónRESUMEN
We examined the mRNA expression of cytokines, chemokines, integrins, and selectins in colon lesions of rat colitis with a semi-quantitative RT-PCR assay. Rat colitis was induced by trinitrobenzene sulfonic acid (TNBS) in 50% ethanol. Within 24 h, an acute inflammation occurred with hyperemia, edema, necrosis and an intense infiltration of granulocytes in the mucosa. The lesion proceeded into a T-lymphocyte/monocyte-driven chronic inflammation for two weeks and healed in 6 weeks. An acute inflammation recurred at the same site when the recovered animals were systemically injected with TNBS. We isolated RNA from colon tissue at 24 h, 1, 2, 4, 6 weeks after TNBS treatment and from the relapsed animals. The mRNA for cytokines IL-1beta, IL-6, IL-10 and the chemokines CINC, MIP-1alpha, MCP-1 were significantly (P < 0.05) elevated and persisted for 2 weeks, decreased in 6 weeks and increased again during relapse. IFN-gamma mRNA stayed at control levels initially, but increased dramatically in the second weeks of chronic inflammation as well as in relapse. The mRNA levels of adhesion molecules, ICAM-1, VCAM-1, the mucosal homing integrin beta7 as well as P- and E-selectin were greatly enhanced between 1 and 3 weeks. The data showed that the chronically inflamed tissue expresses a time-dependent changing pattern of TH1 cytokines and adhesion molecules that maintain the infiltration and activation of inflammatory cells and tissue injury.
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Moléculas de Adhesión Celular/genética , Colitis/genética , Citocinas/genética , Regulación de la Expresión Génica/efectos de los fármacos , Haptenos/toxicidad , Cadenas beta de Integrinas , ARN Mensajero/biosíntesis , Ácido Trinitrobencenosulfónico/toxicidad , Animales , Moléculas de Adhesión Celular/biosíntesis , Enfermedad Crónica , Colitis/inducido químicamente , Colitis/inmunología , Colitis/patología , Citocinas/biosíntesis , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Selectina E/biosíntesis , Selectina E/genética , Granulocitos/patología , Enfermedades Inflamatorias del Intestino/genética , Enfermedades Inflamatorias del Intestino/inmunología , Enfermedades Inflamatorias del Intestino/metabolismo , Enfermedades Inflamatorias del Intestino/patología , Integrinas/biosíntesis , Integrinas/genética , Molécula 1 de Adhesión Intercelular/biosíntesis , Molécula 1 de Adhesión Intercelular/genética , Interferón gamma/biosíntesis , Interferón gamma/genética , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Monocitos/patología , Selectina-P/biosíntesis , Selectina-P/genética , Ratas , Ratas Sprague-Dawley , Recurrencia , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Linfocitos T/patología , Transcripción Genética/efectos de los fármacos , Molécula 1 de Adhesión Celular Vascular/biosíntesis , Molécula 1 de Adhesión Celular Vascular/genéticaRESUMEN
We report on a noniterative method for coherent diffractive imaging based on a specially designed multipinhole (MP) plate. We demonstrated that the complex amplitude of the wavefront penetrating through an MP plate inserted between the specimen and the detector plane can be directly extracted from the Fourier transform of a single far-field diffraction intensity pattern without need of any iterative algorithm. A form of scanning diffractive imaging based on a rotatable MP plate is also demonstrated, which provides a feasible approach for lensless diffractive imaging of complex-valued objects.
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We examine the quantitative condition which has been widely used as a criterion for the adiabatic approximation but was recently found insufficient. Our results indicate that the usual quantitative condition is sufficient for a special class of quantum mechanical systems. For general systems, it may not be sufficient, but it, along with additional conditions, is sufficient. The usual quantitative condition and the additional conditions constitute a general criterion for the validity of the adiabatic approximation, which is applicable to all N-dimensional quantum systems. Moreover, we illustrate the use of the general quantitative criterion in some physical models.
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In this Letter, we point out that the widely used quantitative conditions in the adiabatic theorem are insufficient in that they do not guarantee the validity of the adiabatic approximation. We also reexamine the inconsistency issue raised by Marzlin and Sanders [Phys. Rev. Lett. 93, 160408 (2004)] and elucidate the underlying cause.
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In this paper, we examine three approaches for comparing several treatments with a control with use of binary response data. The first approach relies on asymptotic theory applied to the Freeman-Tukey transformation of the observed proportions. The second finds an acceptance region based on the binomial distributions estimated under the joint null hypotheses. The third approach applies Dunnett's procedure to the binary data. We evaluated the actual overall type I error rates of the Freeman-Tukey test and Dunnett's procedure using both simulation and binomial calculations while we assessed those of the binomial approach using simulation. Based upon their capability to preserve the desirable overall type I error rate, we provide recommendations regarding the choices among the three approaches for various occasions. In addition, we provide comments on the power of these three approaches.
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Interpretación Estadística de Datos , Modelos Estadísticos , Ensayos Clínicos Controlados Aleatorios como Asunto/estadística & datos numéricos , Distribución Binomial , Relación Dosis-Respuesta a Droga , HumanosRESUMEN
A kinematic approach to the geometric phase for mixed quantal states in nonunitary evolution is proposed. This phase is manifestly gauge invariant and can be experimentally tested in interferometry. It leads to well-known results when the evolution is unitary.
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The changes in membrane structural properties occurring during the process of ATP depletion-induced cell injury in adherent human astrocytoma cells (UC-11 MG) were studied with two epifluorescence techniques: 1) steady-state fluorescence anisotropy (r) to examine microstructural changes in the membrane phospholipids and 2) fluorescence redistribution after photobleaching (FRAP) to examine membrane fluidity changes. A new method for r measurement was established that provides the unique advantage of simultaneously monitoring both vertical and horizontal polarized fluorescence emissions needed for the calculation of r. In this study, r in the astrocytoma cells labeled with 1-(4-trimethylammonium phenyl)-6-phenyl-1,3,5-hexatriene p-toluenesulfonate was shown to remain stable for up to 90 min. However, when the cells were treated with 75 microM iodoacetic acid (IAA), a metabolic inhibitor that induces rapid depletion of cellular ATP, r continually decreased, indicating a decrease in membrane lipid order and perturbation of the bilayer structure. This decrease in r could be prevented by the pretreatment of cells with lipophilic antioxidants such as tirilazad or gossypol. Tirilazad itself caused a significant increase in r, suggesting that tirilazad intercalates into the membrane bilayer and profoundly increases the lipid order in uninjured cells. Gossypol, however, did not exhibit this property. Further investigations into these phenomena with FRAP confirmed the r results and indicated that membrane fluidity increased while its structure became less rigid during the process of ATP-induced cell injury. In addition, lipophilic antioxidants prevented the membrane structural aberrations induced by IAA. Experimental results suggest that different mechanisms of cytoprotective action may exist for tirilazad and the antioxidant gossypol. Gossypol appears to prevent or delay the observed cell injury entirely because of its antioxidant action, whereas tirilazad's protection is mediated not only via its antioxidant activity, but also by its ability to increase cell membrane lipid order.