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3.
Front Psychol ; 14: 1150998, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37260960

RESUMEN

Objective: The study aimed to analyze the current status and reasons for the neglect of the psychological need of patients with common skin diseases. Methods: This cross-sectional study was conducted in China using an online self-assessment questionnaire distributed via social media. Demographic, clinical and psychological data were collected, and the main outcomes, i.e., depression (evaluated using the 9-item Patient Health Questionnaire, PHQ-9) and anxiety (evaluated using Generalized Anxiety Disorder-7, GAD-7). Multivariate regression analysis was used for the prediction of variates of mental health service seeking behaviors. Results: A total of 1,010 patients participated in the survey, and 273 (27.0%) patients met the "with need" criteria, i.e., having the need for mental health intervention but not being treated. In the multivariate regression model, income (OR = 0.80, 95%CI: 0.65-0.99), duration of disease (OR = 0.68, 95%CI: 0.49-0.95) and suicide ideation (OR = 2.10, 95%CI: 1.14-3.87) were significant factors. For patients who did not receive mental health care, the lack of knowledge about the availability of mental health services, lack of knowledge of where to seek help, concerns about the side effects of treatment, failure to seek treatment for severe skin diseases, and absence of current psychological distress were associated with their need for psychological intervention. Conclusion: This study examined the current status of the need for psychological intervention and the reasons why the need was unmet in patients with skin diseases. Due to the confusion and a lack of knowledge about their mental health issues, mental health services are often underutilized.

4.
Sci Bull (Beijing) ; 67(15): 1522-1525, 2022 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-36546275
5.
Rep Prog Phys ; 86(2)2022 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-36395499

RESUMEN

The past decades witnessed the golden era of hadron physics. Many excited open heavy flavor mesons and baryons have been observed since 2017. We shall provide an updated review of the recent experimental and theoretical progresses in this active field. Besides the conventional heavy hadrons, we shall also review the recently observed open heavy flavor tetraquark statesX(2900) andTcc+(3875)as well as the hidden heavy flavor multiquark statesX(6900),Pcs(4459)0,Zcs(3985)-,Zcs(4000)+, andZcs(4220)+. We will also cover the recent progresses on the glueballs and light hybrid mesons, which are the direct manifestations of the non-AbelianSU(3) gauge interaction of the Quantum Chromodynamics in the low-energy region.

6.
Phys Rev Lett ; 128(11): 112001, 2022 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-35363019

RESUMEN

A novel framework is proposed to extract near-threshold resonant states from finite-volume energy levels of lattice QCD and is applied to elucidate structures of the positive parity D_{s}. The quark model, the quark-pair-creation mechanism and D^{(*)}K interaction are incorporated into the Hamiltonian effective field theory. The bare 1^{+} cs[over ¯] states are almost purely given by the states with heavy-quark spin bases. The physical D_{s0}^{*}(2317) and D_{s1}^{*}(2460) are the mixtures of bare cs[over ¯] core and D^{(*)}K component, while the D_{s1}^{*}(2536) and D_{s2}^{*}(2573) are almost dominated by bare cs[over ¯]. Furthermore, our model reproduces the clear level crossing of the D_{s1}^{*}(2536) with the scattering state at a finite volume.

7.
Zool Res ; 42(4): 502-513, 2021 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-34254744

RESUMEN

Persistent uplift means the Qinghai-Tibet Plateau (QTP) is an ideal natural laboratory to investigate genome evolution and adaptation within highland environments. However, how paleogeographic and paleoclimatic events influence the genome and population of endemic fish species remains unclear. Glyptosternon maculatum is an ancient endemic fish found on the QTP and the only critically endangered species in the Sisoridae family. Here, we found that major transposons in the G. maculatum genome showed episodic bursts, consistent with contemporaneous geological and climatic events during the QTP formation. Notably, histone genes showed significant expansion in the G. maculatum genome, which may be mediated by long interspersed nuclear elements (LINE) repetitive element duplications. Population analysis showed that ancestral G. maculatum populations experienced two significant depressions 2.6 million years ago (Mya) and 10 000 years ago, exhibiting excellent synchronization with Quaternary glaciation and the Younger Dryas, respectively. Thus, we propose that paleogeography and paleoclimate were dominating driving forces for population dynamics in endemic fish on the QTP. Tectonic movements and temperature fluctuation likely destroyed the habitat and disrupted the drainage connectivity among populations. These factors may have caused severe bottlenecks and limited migration among ancestral G. maculatum populations, resulting in the low genetic diversity and endangered status of the species today.


Asunto(s)
Adaptación Fisiológica , Evolución Biológica , Ecosistema , Peces/genética , Genoma , Animales , Clima , Tibet
8.
Sci Bull (Beijing) ; 66(13): 1288-1295, 2021 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-36654150

RESUMEN

In this work, we investigate the SU(3) flavor symmetry, heavy quark spin symmetry and their breaking effects in the di-meson systems. We prove the existence of the [Formula: see text] , [Formula: see text] , and [Formula: see text] bound states as the consequence of two prerequisites in the SU(3) flavor symmetry and heavy quark spin symmetry. The first prerequisite, the X(3872) as the weakly D‾∗D/D‾D∗ bound state is supported by its mass and decay branching ratios. The second prerequisite, the existence of the [Formula: see text] bound state is supported by the lattice QCD calculation and the observation of χc0(3930) by the LHCb Collaboration. We hope the future experimental analyses can search for these bound states in the B→D(s)(*)D‾(s)(*)h processes (h denotes the light hadrons). The [Formula: see text] bound state is also expected to be reconstructed in the J/ψϕ final state in the B→J/ψϕK decay.

9.
Sci Bull (Beijing) ; 66(20): 2065-2071, 2021 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-36654264

RESUMEN

Recently, the hidden charm tetraquark states Zcs(3985) and Zcs(4000) with strangeness were observed by the BESIII and LHCb collaborations, respectively, which are great breakthroughs for exploring exotic quantum chromodynamics (QCD) structures. The first and foremost question is whether they are the same state. In this work, we explore the implications of the narrower state Zcs(3985) in BESIII and the wider one Zcs(4000) in LHCb as two different states. Within a solvable nonrelativistic effective field theory, we include the possible violations of heavy quark spin symmetry and SU(3) flavor symmetry in a comprehensive approach. If Zcs(3985) and Zcs(4000) are two different states, our results show that Zcs(4000)/Zcs(3985) is the pure (|D‾s∗D〉+/-|D‾sD∗〉)/2 state, and the SU(3) flavor partner of Zc(3900) is Zcs(4000) rather than the Zcs(3985). Another two important consequences are the existence of a tensor D‾s∗D∗ resonance with mass about 4126 MeV and width 13 MeV, and the suppression of the decay mode Zcs(3985)→J/ψK. The two consequences can be tested in experiments and distinguish the two-state interpretation from the one-state scheme.


Asunto(s)
Altruismo , Existencialismo , Alimentos , Vibración
10.
Sci Bull (Beijing) ; 65(23): 1952-1953, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36659046
11.
Sci Bull (Beijing) ; 65(23): 1994-2000, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36659057

RESUMEN

We study strong decays of the possible fully-charm tetraquarks recently observed by LHCb, and calculate their relative branching ratios through the Fierz rearrangement. Together with our previous QCD sum rule study, our results suggest that the broad structure around 6.2-6.8 GeV can be interpreted as an S-wave ccc¯c¯ tetraquark state with JPC=0++ or 2++, and the narrow structure around 6.9 GeV can be interpreted as a P-wave one with JPC=0-+ or 1-+. These structures were observed in the di-J/ψ invariant mass spectrum, and we propose to confirm them in the di-ηc,J/ψhc,ηcχc0, and ηcχc1 channels. We also propose to search for their partner states having the negative charge-conjugation parity in the J/ψηc,J/ψχc0,J/ψχc1, and ηchc channels.

12.
Rep Prog Phys ; 80(7): 076201, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28252448

RESUMEN

Since the discovery of the first charmed meson in 1976, many open-charm and open-bottom hadrons were observed. In 2003 two narrow charm-strange states [Formula: see text] and D s1(2460) were discovered by the BaBar and CLEO Collaborations, respectively. After that, more excited heavy hadrons were reported. In this work, we review the experimental and theoretical progress in this field.

13.
Phys Rev Lett ; 117(2): 022002, 2016 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-27447501

RESUMEN

We investigate the recent evidence for a charged X(5568) meson as an exotic open-flavor tetraquark state sub[over ¯]d[over ¯] with J^{P}=0^{+}/1^{+} in the framework of QCD sum rules. We use the color antisymmetric [3[over ¯]_{c}]_{su}⊗[3_{c}]_{b[over ¯]d[over ¯]} tetraquark currents in both scalar and axial-vector channels to perform evaluations and numerical analyses. Our results imply that the X(5568) can be interpreted as both the scalar sub[over ¯]d[over ¯] tetraquark state and the axial-vector one, which are in good agreement with the experimental measurement. We also discuss the possible decay patterns of the X(5568) and suggest to search for its neutral partner in the radiative decay into B_{s}^{0}γ and B_{s}^{*}γ, which can be used to determine its spin-parity quantum numbers. Moreover, we predict its charmed partner state around 2.55 GeV with the quark content suc[over ¯]d[over ¯] and J^{P}=0^{+}/1^{+}.

14.
Sci Rep ; 6: 19029, 2016 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-26754549

RESUMEN

Orchids make up about 10% of all seed plant species, have great economical value, and are of specific scientific interest because of their renowned flowers and ecological adaptations. Here, we report the first draft genome sequence of a lithophytic orchid, Dendrobium catenatum. We predict 28,910 protein-coding genes, and find evidence of a whole genome duplication shared with Phalaenopsis. We observed the expansion of many resistance-related genes, suggesting a powerful immune system responsible for adaptation to a wide range of ecological niches. We also discovered extensive duplication of genes involved in glucomannan synthase activities, likely related to the synthesis of medicinal polysaccharides. Expansion of MADS-box gene clades ANR1, StMADS11, and MIKC(*), involved in the regulation of development and growth, suggests that these expansions are associated with the astonishing diversity of plant architecture in the genus Dendrobium. On the contrary, members of the type I MADS box gene family are missing, which might explain the loss of the endospermous seed. The findings reported here will be important for future studies into polysaccharide synthesis, adaptations to diverse environments and flower architecture of Orchidaceae.


Asunto(s)
Evolución Biológica , Dendrobium/enzimología , Dendrobium/genética , Flores/crecimiento & desarrollo , Genoma de Planta , Glicosiltransferasas/genética , Secuencia de Bases , Vías Biosintéticas , Evolución Molecular , Flores/genética , Genes de Plantas , Glicosiltransferasas/metabolismo , Proteínas de Dominio MADS/genética , Familia de Multigenes , Filogenia , Análisis de Secuencia de ADN
15.
Phys Rev Lett ; 115(17): 172001, 2015 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-26551105

RESUMEN

Inspired by P(c)(4380) and P(c)(4450) recently observed by LHCb, a QCD sum rule investigation is performed, by which they can be identified as exotic hidden-charm pentaquarks composed of an anticharmed meson and a charmed baryon. Our results suggest that P(c)(4380) and P(c)(4450) have quantum numbers J(P)=3/2(-) and 5/2(+), respectively. Furthermore, two extra hidden-charm pentaqurks with configurations D̅Σ(c)(*) and D̅(*)Σ(c)(*) are predicted, which have spin-parity quantum numbers J(P)=3/2(-) and J(P)=5/2(+), respectively. As an important extension, the mass predictions of hidden-bottom pentaquarks are also given. Searches for these partners of P(c)(4380) and P(c)(4450) are especially accessible at future experiments like LHCb and BelleII.

16.
Phys Rev Lett ; 115(13): 132002, 2015 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-26451546

RESUMEN

The LHCb Collaboration at the Large Hadron Collider at CERN discovered two pentaquark states P_{c}(4380) and P_{c}(4450). These two hidden-charm states are interpreted as the loosely bound Σ_{c}(2455)D^{*} and Σ_{c}^{*}(2520)D^{*} molecular states in the boson exchange interaction model, which provides an explanation for why the experimental width of P_{c}(4450) is much narrower than that of P_{c}(4380). The discovery of the new resonances P_{c}(4380) and P_{c}(4450), indeed, opens a new page for hadron physics. The partners of P_{c}(4380) and P_{c}(4450) should be pursued in future experiments.

17.
Phys Rev Lett ; 91(23): 232002, 2003 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-14683174

RESUMEN

We estimate the mass of the pentaquark state with QCD sum rules and find that pentaquark states with isospin I=0,1,2 lie close to each other around (1.55+/-0.15) GeV. The experimentally observed baryon resonance Theta(+)(1540) with S=+1 can be consistently identified as a pentaquark state if its J(P)=1 / 2(-). Such a state is expected in QCD. If its parity is positive, this pentaquark state is really exotic. The outstanding issue now is to determine its quantum numbers experimentally.

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