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1.
Phys Rev Lett ; 132(10): 100803, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38518317

RESUMO

Quantum many-body interactions can induce quantum entanglement among particles, rendering them valuable resources for quantum-enhanced sensing. In this work, we establish a link between the bound on the growth of the quantum Fisher information and the Lieb-Robinson bound, which characterizes the operator growth in locally interacting quantum many-body systems. We show that for initial separable states, despite the use of local many-body interactions, the precision cannot surpass the shot noise limit at all times. This conclusion also holds for an initial state that is the nondegenerate ground state of a local and gapped Hamiltonian. These findings strongly hint that when one can only prepare separable initial states, nonlocal and long-range interactions are essential resources for surpassing the shot noise limit. This observation is confirmed through numerical analysis on the long-range Ising model. Our results bridge the field of many-body quantum sensing and operator growth in many-body quantum systems and open the possibility to investigate the interplay between quantum sensing and control, many-body physics and information scrambling.

2.
Nat Commun ; 14(1): 7803, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38016956

RESUMO

Indicine cattle, also referred to as zebu (Bos taurus indicus), play a central role in pastoral communities across a wide range of agro-ecosystems, from extremely hot semiarid regions to hot humid tropical regions. However, their adaptive genetic changes following their dispersal into East Asia from the Indian subcontinent have remained poorly documented. Here, we characterize their global genetic diversity using high-quality whole-genome sequencing data from 354 indicine cattle of 57 breeds/populations, including major indicine phylogeographic groups worldwide. We reveal their probable migration into East Asia was along a coastal route rather than inland routes and we detected introgression from other bovine species. Genomic regions carrying morphology-, immune-, and heat-tolerance-related genes underwent divergent selection according to Asian agro-ecologies. We identify distinct sets of loci that contain promising candidate variants for adaptation to hot semi-arid and hot humid tropical ecosystems. Our results indicate that the rapid and successful adaptation of East Asian indicine cattle to hot humid environments was promoted by localized introgression from banteng and/or gaur. Our findings provide insights into the history and environmental adaptation of indicine cattle.


Assuntos
Evolução Biológica , Ecossistema , Animais , Bovinos , Alelos , Variação Genética , Sequenciamento Completo do Genoma , Polimorfismo de Nucleotídeo Único
3.
Anim Genet ; 54(6): 731-742, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37796667

RESUMO

Over the years, indigenous cattle have not only played an essential role in securing primary food sources but have also been utilized for labor by humans, making them invaluable genetic resources. The Zhaotong cattle, a native Chinese breed from the Yunnan province, possess excellent meat quality and resistance to heat and humidity. Here we used whole genome sequencing data of 104 animals to delve into the population structure, genomic diversity and potential positive selection signals in Zhaotong cattle. The findings of this study demonstrate that the genetic composition of Zhaotong cattle was primarily derived from Chinese indicine cattle and East Asian cattle. The nucleotide diversity of Zhaotong cattle was only lower than that of Chinese indicine cattle, which was much higher than that of other taurine cattle. Genome-wide selection scans detected a series of positive candidate regions containing multiple key genes related to bone development and metabolism (CA10, GABRG3, GLDN and NOTUM), meat quality traits (ALG8, LINGO2, MYO5B, PRKG1 and GABRB1), immune response (ADA2, BMF, LEF1 and PAK6) and heat resistance (EIF2AK4 and LEF1). In summary, this study supplies essential genetic insights into the genome diversity within Zhaotong cattle and provides a foundational framework for comprehending the genetic basis of indigenous cattle breeds.


Assuntos
Genoma , Polimorfismo de Nucleotídeo Único , Humanos , Bovinos/genética , Animais , China , Genômica , Fenótipo , Proteínas Serina-Treonina Quinases/genética
4.
Rep Prog Phys ; 85(11)2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36170807

RESUMO

Over the past two decades quantum engineering has made significant advances in our ability to create genuine quantum many-body systems using ultracold atoms. In particular, some prototypical exactly solvable Yang-Baxter systems have been successfully realized allowing us to confront elegant and sophisticated exact solutions of these systems with their experimental counterparts. The new experimental developments show a variety of fundamental one-dimensional (1D) phenomena, ranging from the generalized hydrodynamics to dynamical fermionization, Tomonaga-Luttinger liquids, collective excitations, fractional exclusion statistics, quantum holonomy, spin-charge separation, competing orders with high spin symmetry and quantum impurity problems. This article briefly reviews these developments and provides rigorous understanding of those observed phenomena based on the exact solutions while highlighting the uniqueness of 1D quantum physics. The precision of atomic physics realizations of integrable many-body problems continues to inspire significant developments in mathematics and physics while at the same time offering the prospect to contribute to future quantum technology.

5.
Biology (Basel) ; 11(9)2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-36138806

RESUMO

Dabieshan cattle are a typical breed of southern Chinese cattle that have the characteristics of muscularity, excellent meat quality and tolerance to temperature and humidity. Based on 148 whole-genome data, our analysis disclosed the ancestry components of Dabieshan cattle with Chinese indicine (0.857) and East Asian taurine (0.139). The Dabieshan genome demonstrated a higher genomic diversity compared with the other eight populations, supported by the observed nucleotide diversity, linkage disequilibrium decay and runs of homozygosity. The candidate genes were detected by a selective sweep, which might relate to the fertility (GPX5, GPX6), feed efficiency (SLC2A5), immune response (IGLL1, BOLA-DQA2, BOLA-DQB), heat resistance (DnaJC1, DnaJC13, HSPA4), fat deposition (MLLT10) and the coat color (ASIP). We also identified the "East Asian taurine-like" segments in Dabieshan cattle, which might contribute to meat quality traits. The results revealed by the unique and valuable genomic data can build a foundation for the genetic improvement and conservation of genetic resources for indigenous cattle breeds.

6.
Science ; 376(6599): 1305-1308, 2022 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-35709259

RESUMO

Ultracold atoms confined to periodic potentials have proven to be a powerful tool for quantum simulation of complex many-body systems. We confine fermions to one dimension to realize the Tomonaga-Luttinger liquid model, which describes the highly collective nature of their low-energy excitations. We use Bragg spectroscopy to directly excite either the spin or charge waves for various strengths of repulsive interaction. We observe that the velocity of the spin and charge excitations shift in opposite directions with increasing interaction, a hallmark of spin-charge separation. The excitation spectra are in quantitative agreement with the exact solution of the Yang-Gaudin model and the Tomonaga-Luttinger liquid theory. Furthermore, we identify effects of nonlinear corrections to this theory that arise from band curvature and back-scattering.

7.
Natl Sci Rev ; 9(12): nwac027, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36726638

RESUMO

Quantum statistics plays a fundamental role in the laws of nature. Haldane fractional exclusion statistics (FES) generalizes the Pauli exclusion statistics, and can emerge in the properties of elementary particles and hole excitations of a quantum system consisting of conventional bosons or fermions. FES has a long history of intensive studies, but its simple realization in interacting physical systems is rare. Here we report a simple non-mutual FES that depicts the particle-hole symmetry breaking in interacting Bose gases at a quantum critical point. We show that the FES distribution directly comes from particle-hole symmetry breaking. Based on exact solutions, quantum Monte Carlo simulations and experiments, we find that, over a wide range of interaction strengths, the macroscopic physical properties of these gases are determined by non-interacting quasi-particles that obey non-mutual FES of the same form in one and two dimensions. Whereas strongly interacting Bose gases reach full fermionization in one dimension, they exhibit incomplete fermionization in two dimensions. Our results provide a generic connection between interaction-induced particle-hole symmetry breaking (depicted by FES) and macroscopic properties of many-body systems in arbitrary dimensions. Our work lays the groundwork for using FES to explore quantum criticality and other novel many-body phenomena in strongly correlated quantum systems.

8.
Phys Rev Lett ; 127(10): 100406, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34533338

RESUMO

Recent experiments on quantum walks (QWs) demonstrated a full control over the statistics-dependent walks of single particles and two particles in one-dimensional lattices. However, little is known about the general characterization of QWs at the many-body level. Here, we rigorously study QWs, Bloch oscillations, and the quantum Fisher information for three indistinguishable bosons and fermions in one-dimensional lattices using a time-evolving block decimation algorithm and many-body perturbation theory. We show that such strongly correlated QWs not only give rise to statistics-and-interaction-dependent ballistic transports of scattering states and of two- and three-body bound states but also allow a quantum enhanced precision measurement of the gravitational force. In contrast to the QWs of the fermions, the QWs of three bosons exhibit strongly correlated Bloch oscillations, which present a surprising time scaling t^{3} of the Fisher information below a characteristic time t_{0} and saturate to the fundamental limit of t^{2} for t>t_{0}.

9.
Phys Rev Lett ; 125(19): 190401, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33216574

RESUMO

At low temperature, collective excitations of one-dimensional (1D) interacting fermions exhibit spin-charge separation, a unique feature predicted by the Tomonaga-Luttinger liquid (TLL) theory, but a rigorous understanding remains challenging. Using the thermodynamic Bethe ansatz (TBA) formalism, we analytically derive universal properties of a 1D repulsive spin-1/2 Fermi gas with arbitrary interaction strength. We show how spin-charge separation emerges from the exact TBA formalism, and how it is disrupted by the interplay between the two degrees of freedom that brings us beyond the TLL paradigm. Based on the exact low-lying excitation spectra, we further evaluate the spin and charge dynamical structure factors (DSFs). The peaks of the DSFs exhibit distinguishable propagating velocities of spin and charge as functions of interaction strength, which can be observed by Bragg spectroscopy with ultracold atoms.

11.
Clin Respir J ; 14(10): 973-979, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32621542

RESUMO

INTRODUCTION: High-altitude pulmonary edema (HAPE) is caused by the interaction of both genetic and environmental risk factors. OBJECTIVES: In this study, we aimed to explore whether three single nucleotide polymorphisms (SNPs) in CYP2C19 gene influenced the HAPE susceptibility in the Chinese Han population. METHODS: We recruited 238 cases and 230 controls between January 2018 and October 2018 from the Affiliated Hospital of Xizang Minzu University. The relationship between CYP2C19 gene polymorphisms and HAPE was studied by association analysis. Genotyping was performed using the Agena MassARRAY platform and the statistical analysis was performed using Chi-squared test, independent sample t test, genetic model analysis and haplotype analysis. RESULTS: The main finding of our study showed that rs4494250 in CYP2C19 gene was associated with an increased risk of HAPE at age >32 years in the log-additive model (OR = 1.80, 95% CI = 1.05-3.09, P = 0.033). Also, it was observed to be associated with a reduced risk of HAPE at age ≤2 years in the dominant model (A/G-A/A vs G/G, OR = 0.55, 95% CI = 0.31-0.97, P = 0.038) and in the log-additive model (OR = 0.58, 95% CI = 0.35-0.96, P = 0.033). CONCLUSION: Our findings demonstrated that CYP2C19 genetic variants were associated with risk of developing HAPE in Han Chinese population.


Assuntos
Doença da Altitude , Edema Pulmonar , Altitude , Doença da Altitude/genética , Estudos de Casos e Controles , Citocromo P-450 CYP2C19/genética , Predisposição Genética para Doença , Humanos , Recém-Nascido , Polimorfismo de Nucleotídeo Único
12.
Animals (Basel) ; 9(12)2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31775331

RESUMO

The heat shock factor 1 (HSF1) gene is a regulator of the heat stress response, maximizing HSP protein expression survival. In this research, we explored the frequency distribution of a missense mutation (NC_037341.1 g.616087A > G, rs135258919) in the HSF1 gene in Chinese cattle with amino acid substitution, valine to alanine. This mutation could be related to the heat tolerance in Bos indicus. A total of 941 individuals representing 35 Chinese native cattle breeds, combining pure taurine (Angus) and indicine cattle, were used to determine the genotypes of the mutation through PCR and partial DNA sequencing. The results showed significant differences in allele frequencies and their genotypes amongst Chinese cattle from different regions. Allele G or indicine-specific allele frequency diminished from south to north China, while allele A (genotype AA) or the taurine-specific allele had a contrary pattern, which agreed with the distribution of taurine and indicine cattle. According to the association analysis, the NC_037341.1 g.616087A > G (rs135258919) of the bovine HSF1 gene, annual temperature (T), relative humidity (RH), and the temperature humidity index (THI) (p < 0.01) were interrelated closely, which indicated that the NC_037341.1 g.616087A > G of the HSF1 gene is associated with heat tolerance in indicine cattle.

13.
Phys Rev Lett ; 122(18): 180401, 2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-31144880

RESUMO

A large number of symmetry-protected topological (SPT) phases have been hypothesized for strongly interacting spin-1/2 systems in one dimension. Realizing these SPT phases, however, often demands fine-tunings hard to reach experimentally. And the lack of analytical solutions hinders the understanding of their many-body wave functions. Here we show that two kinds of SPT phases naturally arise for ultracold polar molecules confined in a zigzag optical lattice. This system, motivated by recent experiments, is described by a spin model whose exchange couplings can be tuned by an external field to reach parameter regions not studied before for spin chains or ladders. Within the enlarged parameter space, we find the ground state wave function can be obtained exactly along a line and at a special point, for these two phases, respectively. These exact solutions provide a clear physical picture for the SPT phases and their edge excitations. We further obtain the phase diagram by using infinite time-evolving block decimation and discuss the phase transitions between the two SPT phases and their experimental signatures.

14.
Phys Rev Lett ; 119(16): 165701, 2017 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-29099230

RESUMO

We experimentally investigate the quantum criticality and Tomonaga-Luttinger liquid (TLL) behavior within one-dimensional (1D) ultracold atomic gases. Based on the measured density profiles at different temperatures, the universal scaling laws of thermodynamic quantities are observed. The quantum critical regime and the relevant crossover temperatures are determined through the double-peak structure of the specific heat. In the TLL regime, we obtain the Luttinger parameter by probing sound propagation. Furthermore, a characteristic power-law behavior emerges in the measured momentum distributions of the 1D ultracold gas, confirming the existence of the TLL.

15.
Biosens Bioelectron ; 64: 94-101, 2015 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-25194802

RESUMO

In this study, we designed a novel molecularly imprinted polymer (MIP), oligomeric methyl silsesquioxane (O-MSSQ)-TiO2 composite sol, which was made using a sol-gel reaction. This polymer has structural rigidity and high surface area of O-MSSQ, as well as high bio-compatibility and relatively good conductivity of the TiO2. Next, a sensitive and selective imprinted electrochemical sensor was successfully constructed for the direct detection of procainamide hydrochloride by molecularly imprinting a film onto the surface of a glassy carbon electrode. Adding TiO2 resulted in a noticeable enhancement in the sensitivity of the MIP sensor. The performance of the O-MSSQ-TiO2 film was discussed, and the optimal conditions for detection were determined. The oxidative peak current increased linearly with the concentration of procainamide hydrochloride in the range of 4.00 × 10(-9)-4.97 × 10(-5) M using differential pulse voltammetry, and the detection limit was 1.30 × 10(-9) M with S/N = 3. Furthermore, the sensor was applied to determine the procainamide hydrochloride content in a human blood serum sample. The recoveries of the sensors varied from 96.77% to 101.35%, indicating that the prepared sensor might be promising for the determination of procainamide hydrochloride in clinical tests. Moreover, the imprinted electrochemical sensor was used to selectively detect procainamide hydrochloride. The analytical application was conducted successfully and yielded accurate and precise results.


Assuntos
Antiarrítmicos/sangue , Carbono/química , Impressão Molecular/métodos , Compostos de Organossilício/química , Procainamida/sangue , Titânio/química , Eletrodos , Humanos , Limite de Detecção , Transição de Fase
16.
Phys Rev Lett ; 103(14): 140404, 2009 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-19905551

RESUMO

We study the thermodynamics of a one-dimensional attractive Fermi gas (the Gaudin-Yang model) with spin imbalance. The exact solution has been known from the thermodynamic Bethe ansatz for decades, but it involves an infinite number of coupled nonlinear integral equations whose physics is difficult to extract. Here the solution is analytically reduced to a simple, powerful set of four algebraic equations. The simplified equations become universal and exact in the experimental regime of strong interaction and relatively low temperature. Using the new formulation, we discuss the qualitative features of finite-temperature crossover and make quantitative predictions on the density profiles in traps. We propose a practical two-stage scheme to achieve accurate thermometry for a trapped spin-imbalanced Fermi gas.

17.
Gynecol Endocrinol ; 25(10): 647-52, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19557594

RESUMO

OBJECTIVE: To investigate the influence of gestational diabetes mellitus (GDM) on the change of SHBG in fetus. METHOD: Forty-eight pregnant women with GDM and 86 women with normal pregnancy were included in the study. The following were measured in the serums of pregnant women, amniotic fluids, and umbilical cord serums: glucose, insulin, peptide-C, SHBG, and sex hormones. RESULTS: SHBGs in pregnant women's serums were, when compared with the control group: in male fetuses 308.06 +/- 55.64 vs. 445.21 +/- 50.07 (p < 0.01) and in female fetuses 312.38 +/- 56.61 vs. 451.05 +/- 52.87 (p < 0.01). When comparing the levels of SHBGs in amniotic fluids, inclusive of the control group, the following were in male fetuses 8.35 +/- 1.07 vs. 8.41 +/- 1.09 (p = NS) and in female fetuses 8.31 +/- 0.97 vs. 8.39 +/- 0.94 (p = NS). For the levels of SHBGs in umbilical cord serums and comparison to the control group were: in male fetuses 41.44 +/- 8.83 vs. 40.24 +/- 7.50 (p = NS) and in female fetuses 39.93 +/- 7.04 vs. 39.69 +/- 7.16 (p = NS). The concentration of SHBG in amniotic fluid had no significant relationship to glucose, dehydroepiandrosterone (DHEAS), estradiol, and total and free testosterone, but had an extremely negatively correlated to insulin and peptide-C (p < 0.01) in GDM group. CONCLUSION: Although the concentration of SHBG does not change in fetus when pregnant woman is complicated with GDM, it is already influenced by the fetal regulation on hyperinsulinemia.


Assuntos
Diabetes Gestacional/metabolismo , Troca Materno-Fetal , Globulina de Ligação a Hormônio Sexual/metabolismo , Adulto , Líquido Amniótico/metabolismo , Glicemia/metabolismo , Cesárea , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Recém-Nascido , Insulina/metabolismo , Masculino , Gravidez , Estatísticas não Paramétricas
18.
Phys Rev Lett ; 91(21): 217202, 2003 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-14683332

RESUMO

We investigate the thermal and magnetic properties of the integrable su(4) ladder model by means of the quantum transfer matrix method. The magnetic susceptibility, specific heat, magnetic entropy, and high field magnetization are evaluated from the free energy derived via the recently proposed method of high temperature expansion for exactly solved models. We show that the integrable model can be used to describe the physics of the strong coupling ladder compounds. Excellent agreement is seen between the theoretical results and the experimental data for the known ladder compounds (5IAP)2CuBr4.2H(2)O, Cu2(C5H12N2)2Cl4, etc.

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