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1.
Front Psychiatry ; 14: 1297411, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38106999

RESUMO

Introduction: The etiology and pathophysiology of major depressive disorders (MDDs) remain unclear. Increasing evidence has demonstrated that essential trace elements (ETEs), such as iodine (I), zinc (Zn), copper (Cu), selenium (Se), cobalt (Co), and molybdenum (Mo), play vital roles in MDDs. Methods: In total, 72 patients with MDD and 75 healthy controls (HCs) in the Zhumadian Second People's Hospital, Henan Province, China were recruited in our study. The levels of different ETEs were examined in both serum and urine, using an inductively coupled plasma mass spectrometer (ICP-MS), for both the MDD patients and HCs. Results: The serum levels of I, Se, Cu, and Mo were significantly lower in the MDD patients compared to the HCs (p < 0.05), and the urinary levels of I and Zn were significantly higher in the MDD patients compared to the HCs (p < 0.05). The serum concentration of I (Q3: OR = 0.210, Q4: OR = 0.272) was negatively associated with MDD after adjusting for potential confounders, including age, gender, and BMI, and the urinary concentration of I (Q4: OR = 2.952) was positively associated. Conclusions: The higher levels of I, Se, Cu, and Mo in serum might be protective against the development of MDD, and the excess I and Zn in urine may be associated with MDD pathogenesis. Future research needs to gain a deeper understanding of the metabolic pathways of ETEs, especially I, Se, Zn, Cu, and Mo, in MDD, and their role in the pathogenesis of depression.

2.
Front Syst Neurosci ; 15: 704069, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34658801

RESUMO

Objective: Accumulating evidence indicates that inflammation abnormalities may contribute to aggression behaviors in psychotic patients, however, the possible sources of inflammation remain elusive. We aimed to evaluate the associations among aggression, inflammation, and bacterial translocation (BT) in aggression-affected schizophrenia (ScZ) inpatients with 2 weeks of antipsychotics discontinuation. Methods: Serum specimens collected from 112 aggression and 112 non-aggression individuals with ScZ and 56 healthy adults were used for quantifications of inflammation- or BT-related biomarkers. Aggression severity was assessed by Modified Overt Aggression Scale (MOAS). Results: Proinflammation phenotype dominated and leaky gut-induced BT occurred only in cases with ScZ with a history of aggression, and the MOAS score positively related to levels of C-reactive protein, interleukin (IL)-6, IL-1ß, and tumor necrosis factor-α. Furthermore, serum levels of BT-derived lipopolysaccharide (LPS), as well as LPS-responded soluble CD14, were not only positively correlated with levels of above proinflammation mediators but also the total MOAS score and subscore for aggression against objects or others. Conclusion: Our results collectively demonstrate the presence of leaky gut and further correlate BT-derived LPS and soluble CD14 to onset or severity of aggression possibly by driving proinflammation response in inpatients with ScZ, which indicates that BT may be a novel anti-inflammation therapeutic target for aggression prophylaxis.

3.
J Phys Condens Matter ; 30(26): 265502, 2018 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-29775182

RESUMO

We present a theory to address the photoluminescence (PL) intensity and valley polarization (VP) dynamics in monolayer WSe2, under the impact of excitonic dark states of both excitons and biexcitons. We find that the PL intensity of all excitonic channels including intravalley exciton (Xb), intravalley biexciton (XXk,k) and intervalley biexciton (XX[Formula: see text]) in particular for the XXk,k PL is enhanced by laser excitation fluence. In addition, our results indicate the anomalous temperature dependence of PL, i.e. increasing with temperature, as a result of favored phonon assisted dark-to-bright scatterings at high temperatures. Moreover, we observe that the PL is almost immune to intervalley scatterings, which trigger the exchange of excitonic states between the two valleys. As far as the valley polarization is concerned, we find that the VP of Xb shrinks as temperature increases, exhibiting opposite temperature response to PL, while the intravalley XXk,k VP is found almost independent of temperature. In contrast to both Xb and XXk,k, the intervalley XX[Formula: see text] VP identically vanishes, because of equal populations of excitons in the K and [Formula: see text] valleys bounded to form intervalley biexcitons. Notably, it is found that the Xb VP much more strongly depends on bright-dark scattering than that of XXk,k, making dark state act as a robust reservoir for valley polarization against intervalley scatterings for Xb at strong bright-dark scatterings, but not for XXk,k. Dark excitonic states enabled enhancement of VP benefits quantum technology for information processing based on the valley degree of freedom in valleytronic devices. Furthermore, the VP has strong dependence on intervalley scattering but maintains essentially constant with excitation fluence. Finally, the dependence of time evolution of PL and VP on temperature and excitation fluence is discussed.

4.
Sci Rep ; 7: 41044, 2017 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-28112197

RESUMO

Photonic quantum computer, quantum communication, quantum metrology and quantum optical technologies rely on the single-photon source (SPS). However, the SPS with valley-polarization remains elusive and the tunability of magneto-optical transition frequency and emission/absorption intensity is restricted, in spite of being highly in demand for valleytronic applications. Here we report a new class of SPSs based on carriers spatially localized in two-dimensional monolayer transition metal dichalcogenide quantum dots (QDs). We demonstrate that the photons are absorbed (or emitted) in the QDs with distinct energy but definite valley-polarization. The spin-coupled valley-polarization is invariant under either spatial or magnetic quantum quantization. However, the magneto-optical absorption peaks undergo a blue shift as the quantization is enhanced. Moreover, the absorption spectrum pattern changes considerably with a variation of Fermi energy. This together with the controllability of absorption spectrum by spatial and magnetic quantizations, offers the possibility of tuning the magneto-optical properties at will, subject to the robust spin-coupled valley polarization.

5.
Phys Rev Lett ; 117(22): 226401, 2016 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-27925749

RESUMO

A persistent spin helix (PSH) is a robust helical spin-density pattern arising in disordered 2D electron gases with Rashba α and Dresselhaus ß spin-orbit (SO) tuned couplings, i.e., α=±ß. Here, we investigate the emergence of a persistent Skyrmion lattice (PSL) resulting from the coherent superposition of PSHs along orthogonal directions-crossed PSHs-in wells with two occupied subbands ν=1, 2. For realistic GaAs wells, we show that the Rashba α_{ν} and Dresselhaus ß_{ν} couplings can be simultaneously tuned to equal strengths but opposite signs, e.g., α_{1}=ß_{1} and α_{2}=-ß_{2}. In this regime, and away from band anticrossings, our noninteracting electron gas sustains a topologically nontrivial Skyrmion-lattice spin-density excitation, which inherits the robustness against spin-independent disorder and interactions from its underlying crossed PSHs. We find that the spin relaxation rate due to the interband SO coupling is comparable to that of the cubic Dresselhaus term as a mechanism of the PSL decay. Near anticrossings, the interband-induced spin mixing leads to unusual spin textures along the energy contours beyond those of the Rahsba-Dresselhaus bands. Our PSL opens up the unique possibility of observing topological phenomena, e.g., topological and Skyrmion Hall effects, in ordinary GaAs wells with noninteracting electrons.

6.
J Phys Condens Matter ; 28(37): 375803, 2016 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-27421077

RESUMO

We report a theoretical investigation on the energy spectrum and the effective Zeeman energy (EZE) in monolayer MoS2 circular quantum dots, subjected to an out-of-plane magnetic field. Interestingly, we observe the emergence of energy-locked modes, depending on the competition between the dot confinement and the applied magnetic field, for either the highest K-valley valence band or the lowest [Formula: see text]-valley conduction band. Moreover, an unusual dot-size-independent EZE behavior of the highest valence and the lowest conduction bands is found. Although the EZEs are insensitive to the variation of quantum confinement, both of them grow linearly with the magnetic field, similar to that in the monolayer MoS2 material. The EZEs along with their 'robustness' against dot confinements open opportunities of a universal magnetic control over the valley degree of freedom, for quantum dots of all sizes.

7.
Zhonghua Wei Chang Wai Ke Za Zhi ; 15(6): 608-10, 2012 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-22736133

RESUMO

OBJECTIVE: To analyze the reasons for reoperation after failed laparoscopic surgery for acute abdomen. METHODS: A retrospective study was performed to review the clinical data of 17 patients who required reoperation after laparoscopic surgery from May 2006 to March 2011. RESULTS: There were 11 males and 6 females with 16-68 years old. The reasons for reoperation were as follows: 13 with abdominal abscess among whom 4 complicated with internal fistula, 1 with residual toothpick, 1 with ileocecal lymphadenoma complicated with bowel obstruction, 1 with obturator hernia, 1 with intestinal vascular malformation. Twelve patients underwent laparoscopic reoperation after conservative treatments were invalid, among whom 5 completed laparoscopic operation successfully and 7 converted to laparotomy. The other 5 patients underwent emergency abdominal operation. All the patients were cured and discharged from hospital 7-21 days postoperatively. CONCLUSION: The laparoscopic technique has unique advantages, but must strictly adhere to the indications of Laparoscopic exploration and strictly follow the surgical operation procedures. In the special condition,and in diagnosis and surgery difficulty,laparoscopic surgery should be timely and decisive conversion to open surgery in the diagnosis and treatment of surgical acute abdomen.


Assuntos
Abdome Agudo/cirurgia , Laparoscopia , Reoperação , Adolescente , Adulto , Idoso , Feminino , Humanos , Laparoscopia/efeitos adversos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Falha de Tratamento , Adulto Jovem
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