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1.
Phys Rev Lett ; 131(2): 020403, 2023 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-37505950

RESUMEN

Efficient methods to access the entanglement of a quantum many-body state, where the complexity generally scales exponentially with the system size N, have long been a concern. Here we propose the Schmidt tensor network state (Schmidt TNS) that efficiently represents the Schmidt decomposition of finite- and even infinite-size quantum states with nontrivial bipartition boundary. The key idea is to represent the Schmidt coefficients (i.e., entanglement spectrum) and transformations in the decomposition to tensor networks (TNs) with linearly scaled complexity versus N. Specifically, the transformations are written as the TNs formed by local unitary tensors, and the Schmidt coefficients are encoded in a positive-definite matrix product state (MPS). Translational invariance can be imposed on the TNs and MPS for the infinite-size cases. The validity of Schmidt TNS is demonstrated by simulating the ground state of the quasi-one-dimensional spin model with geometrical frustration. Our results show that the MPS encoding the Schmidt coefficients is weakly entangled even when the entanglement entropy of the decomposed state is strong. This justifies the efficiency of using MPS to encode the Schmidt coefficients, and promises an exponential speedup on the full-state sampling tasks.

2.
Inorg Chem ; 60(24): 18739-18752, 2021 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-34865470

RESUMEN

In this work, we employed an asymmetric auxiliary organic ligand (1,1,1-trifluoroacetylacetone, Htfac) to further regulate the magnetic relaxation behavior of series of Dy2 single-molecule magnets (SMMs) with a N1,N3-bis(3-methoxysalicylidene)diethylenetriamine (H2L) ligand. Fortunately, an air-stable Dy2 complex, [Dy2(L)2(tfac)2] (1; Htfac = 1,1,1-trifluoroacetylacetone) was obtained at room temperature. A structural analysis indicated that some Dy-O or Dy-N bond lengths for 1 are not in the range of those for the complexes [DyIII2(L)2(acac)2]·2CH2Cl2 (Dy2-acac; Hacac = acetylacetone) and [DyIII2(L)2(hfac)2] (Dy2-hfac; Hhfac = hexafluoroacetylacetone), although the electron-withdrawing ability of tfac- is stronger than that of acac- but weaker than that of hfac-. Additionally, the Dy-O3/O3a (the two O atoms bridged to DyIII ions) bond lengths are also affected by the asymmetrical Htfc ligand. This indicated that the charge distribution of the coordination atoms around DyIII has been modified in 1, which leads to the fine-tuning of the magnetic relaxation behavior of 1. Magnetic studies indicated that the values of effective energy barrier (Ueff) for 1 and its diluted sample (2) are 234.8(3) and 188.0(6) K, respectively, which are both higher than the reported value of 110 K for the complex Dy2-hfac. More interestingly, 1 exhibits a magnetic hysteresis opening when T < 2.5 K at zero field, while the hysteresis loops of 2 are closed at a zero dc field. This discrepancy is due to the weak intramolecular exchange coupling in 2, which cannot overcome the QTM of the single DyIII ion. Ab initio calculations for 1 revealed that the charge distributions of the coordination atoms around DyIII ions were regulated and the intramolecular exchange coupling was indeed improved when the asymmetrical Htfc was employed as a ligand for the synthesis of this kind of Dy2 SMM.

3.
J Oral Maxillofac Surg ; 77(3): 499-514, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30476490

RESUMEN

PURPOSE: Insufficient bone volume compromises the success rate and osseointegration of immediate implantation. The objective of the present study was to engineer bone tissue by using adipose-derived stem cell (ASC) sheets and autologous platelet-rich fibrin (PRF) to enhance new bone formation and osseointegration around dental implants. MATERIAL AND METHODS: The proliferation and osteogenic potential of ASCs treated with autologous PRF were evaluated with CCK-8 assays, alkaline phosphatase staining, and real-time quantitative polymerase chain reaction. A 3-wall bone defect around each immediate implant was generated in the mandible and randomly treated with ASC sheets plus PRF (group A), ASC sheets only (group B), PRF only (group C), or no treatment (group D). Micro-computed tomography, biomechanical tests, fluorescent bone labeling, and histologic assessments were performed to evaluate bone regeneration capacity. RESULTS: The proliferation and osteogenic potential of canine ASCs were markedly enhanced by PRF. Group A exhibited considerably more new bone formation and re-osseointegration (41.17 ± 1.44 and 55.06 ± 0.06%, respectively) than did the other 3 groups. Fluorescent labeling showed that the most rapid bone remodeling activity occurred in group A (P < .05). CONCLUSION: These results suggest that sheets of ASC combined with autologous PRF could be a promising tissue-engineering strategy for bone formation in immediate implantation.


Asunto(s)
Implantes Dentales , Células Madre Mesenquimatosas , Regeneración Ósea , Osteogénesis , Fibrina Rica en Plaquetas , Microtomografía por Rayos X
4.
Med Sci Monit ; 21: 3690-5, 2015 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-26613867

RESUMEN

BACKGROUND Primary Sjögren's syndrome (pSS) is one of the most common chronic systemic autoimmune diseases, and thrombocytopenia is one of the hematological manifestations of pSS. When platelet and endothelial cells are activated, P-selectin is expressed on the cell surface. This study aimed to investigate the role of P-selectin autoantibodies in the pathogenesis of thrombocytopenia in pSS. MATERIAL AND METHODS P-selectin autoantibodies were measured by enzyme-linked immunosorbent assay (ELISA) in 38 pSS patients without thrombocytopenia and 32 pSS patients with thrombocytopenia, 32 idiopathic thrombocytopenic purpura (ITP) patients, and 35 healthy controls. RESULTS The plasma P-selectin autoantibodies (A490) in ITP patients and pSS patients with/without thrombocytopenia were significantly higher than those in healthy controls, but there were no significant differences between ITP patients and pSS patients with thrombocytopenia. The positive rate of P-selectin autoantibodies in pSS patients with thrombocytopenia was significantly higher than that in ITP patients. The platelet count was lower in P-selectin autoantibodies-positive patients, while among pSS patients with thrombocytopenia, the platelet count was lower in P-selectin autoantibodies-positive patients than in P-selectin autoantibodies-negative patients. In ITP patients and pSS patients with thrombocytopenia, the platelet count was lower in P-selectin autoantibodies-positive patients. CONCLUSIONS Elevated plasma P-selectin autoantibodies may play a role in the pathogenesis of thrombocytopenia in pSS patients.


Asunto(s)
Autoanticuerpos/sangre , Selectina-P/inmunología , Síndrome de Sjögren/sangre , Trombocitopenia/sangre , Adolescente , Adulto , Autoanticuerpos/inmunología , Plaquetas/inmunología , Ensayo de Inmunoadsorción Enzimática , Femenino , Citometría de Flujo , Humanos , Masculino , Persona de Mediana Edad , Recuento de Plaquetas , Síndrome de Sjögren/inmunología , Trombocitopenia/inmunología
5.
World J Clin Cases ; 12(11): 1990-1995, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38660553

RESUMEN

BACKGROUND: When an anorectal foreign body is found, its composition and shape should be evaluated, and a timely and effective treatment plan should be developed based on the patient's symptoms to avoid serious complications such as intestinal perforation caused by displacement of the foreign body. CASE SUMMARY: A 54-year-old male was admitted to our outpatient clinic on June 3, 2023, due to a rectal foreign body that had been embedded for more than 24 h. The patient reported using a glass electrode tube to assist in the recovery of prolapsed hemorrhoids, however, the electrode tube was inadvertently inserted into the anus and could not be removed by the patient. During hospitalization, the patient underwent surgery, and the foreign body was dragged into the rectum with the aid of colonoscopy. The anus was dilated with a comb-type pulling hook and an anal fistula pulling hook to widen the anus and remove the foreign body, and the local anal symptoms were then relieved with topical drugs. The patient was allowed to eat and drink, and an entire abdominal Computed tomography (CT) and colonoscopy were reviewed 3 d after surgery. CT revealed no foreign body residue and colonoscopy showed no metal or other residues in the colon and rectum, and no apparent intestinal tract damage. CONCLUSION: The timeliness and rationality of the surgical and therapeutic options for this patient were based on a literature review of the clinical signs and conceivable conditions in such cases. The type, material and the potential risks of rectal foreign bodies should be considered.

6.
Huan Jing Ke Xue ; 43(2): 985-994, 2022 Feb 08.
Artículo en Zh | MEDLINE | ID: mdl-35075872

RESUMEN

In order to select plant materials suitable for the ecological restoration of abandoned mining land, ecological restoration experiments were set up in landfills. The effects of different ecological restoration measures on plant diversity and heavy metal enrichment and migration characteristics were studied. The results showed that under different ecological restoration measures, a total of eight families and 10 species of surviving plants appeared, most of which were herbs. The restoration effect of the arbor shrub and grass plots was the best; the plant coverage reached 100%, and the survival rate was over 69%. The diversity index of the plant community was as follows:arbor shrub grass > shrub grass > joe grass > grass. The dominant plants under different ecological restoration measures were Pinus elliottii, Ligustrum lucidum, Boehmeria nivea, Lagerstroemia indica, and Plantago asiatica. The contents of most heavy metals in plants were higher than the normal values. Among them, the enrichment and transfer coefficients of the leaf stems of P. elliottii and L. indica were close to or greater than 1, showing a strong ability of enrichment and transfer to Cd; these two plants belong to Cd-enrichment type plants. The roots of L. lucidum Ait and P. asiatica, which are root-hoarding plants, had a high retention rate of heavy metals. Boehmeria nivea was a heavy metal-avoidance plant with a low content of heavy metals in each part and had the ability to fix and repair potential soil heavy metal pollution. Considering the diversity of plants and the ability of plant enrichment and migration, the combination of trees, shrubs, and grasses was the best restoration mode. Pinus elliottii, L. indica, and P. asiatica can be the target plants for ecological restoration in the abandoned land of mining areas.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Biodegradación Ambiental , China , Monitoreo del Ambiente , Humanos , Metales Pesados/análisis , Minería , Suelo , Contaminantes del Suelo/análisis
7.
Sci Rep ; 7: 44599, 2017 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-28317884

RESUMEN

A Ser105Ala mutant of the lipase B from Candida antarctica enables 'perhydrolase-only' reactions. At the example of the chemoenzymatic Baeyer-Villiger oxidation of cyclohexanone, we demonstrate that with this mutant selective oxidation can be achieved in deep eutectic solvent while essentially eliminating the undesired hydrolysis reaction of the product.


Asunto(s)
Candida/enzimología , Hidrolasas/metabolismo , Lipasa/metabolismo , Ingeniería de Proteínas/métodos , Biocatálisis , Hidrólisis , Oxidación-Reducción , Solventes , Especificidad por Sustrato
8.
Int J Oral Sci ; 8(4): 213-222, 2016 12 16.
Artículo en Inglés | MEDLINE | ID: mdl-27811845

RESUMEN

Postnatal mesenchymal stem cells have the capacity to differentiate into multiple cell lineages. This study explored the possibility of dental pulp stem cells (DPSCs) for potential application in tendon tissue engineering. The expression of tendon-related markers such as scleraxis, tenascin-C, tenomodulin, eye absent homologue 2, collagens I and VI was detected in dental pulp tissue. Interestingly, under mechanical stimulation, these tendon-related markers were significantly enhanced when DPSCs were seeded in aligned polyglycolic acid (PGA) fibre scaffolds. Furthermore, mature tendon-like tissue was formed after transplantation of DPSC-PGA constructs under mechanical loading conditions in a mouse model. This study demonstrates that DPSCs could be a potential stem cell source for tissue engineering of tendon-like tissue.


Asunto(s)
Pulpa Dental , Células Madre Mesenquimatosas , Tendones , Ingeniería de Tejidos , Animales , Diferenciación Celular , Células Cultivadas , Ratones , Células Madre , Andamios del Tejido
9.
Int J Endocrinol ; 2015: 346938, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25918527

RESUMEN

Background. Pigment epithelium-derived factor (PEDF) is demonstrated to be elevated in diabetes patients. However, no reports have emerged in pregnant women with gestational diabetes mellitus (GDM). This study was undertaken to investigate serum PEDF levels in GDM women and to evaluate PEDF as a biomarker to predict diabetes postpartum. Methods. Serum PEDF concentration and clinical characteristics were detected in the pregnant women with GDM (n = 120) and without GDM (control group, n = 120). Results. PEDF levels were elevated in subjects with GDM versus controls. Univariate correlations showed that serum PEDF levels were positively correlated with fasting glucose and fasting insulin levels, respectively, and negatively correlated with adiponectin. Receiver operating characteristic (ROC) analysis demonstrated that the AUC of serum PEDF for diabetes mellitus in women postpartum was 0.893. Conclusion. Serum PEDF was elevated in pregnant women with GDM, which is probably an early detection marker for predicting development of GDM to diabetes mellitus.

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