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1.
Phys Rev Lett ; 132(9): 092501, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38489643

RESUMO

Three ΔI=1 bands with the πg_{9/2}⊗νg_{9/2} configuration have been identified in _{35}^{74}Br_{39}. Angular distribution, linear polarization, and lifetime measurements were performed to determine the multipolarity, type, mixing ratio, and absolute transition probability of the transitions. By comparing these experimental observations with the corresponding fingerprints and the quantum particle rotor model calculations, the second and third lowest bands are, respectively, suggested as the chiral partner and one-phonon wobbling excitation built on the yrast band. The evidence indicates the first chiral wobbler in nuclei.

2.
Zhonghua Yi Xue Za Zhi ; 101(37): 2968-2974, 2021 Oct 12.
Artigo em Chinês | MEDLINE | ID: mdl-34638186

RESUMO

Objective: To further clarify the mid-and-long term follow-up results of self-designed tibial periosteum-bone complex transplantation in the treatment of Hepple V osteochondral lesion of the talus(OLTs). Methods: The clinical data of 30 patients with Hepple V OLTs who received treatment in the Sports Medicine Center of the First Affiliated Hospital of Army Military Medical University from October 2011 to January 2019 were analyzed. There were 19 males and 11 females with a mean age of (40±11) years. Patients were treated with autogenous tibial periosteum-bone complex transplantation and were followed up for at least 2 years. The Foot and Ankle Outcome Score (FAOS), American Orthopedic Foot and Ankle Society (AOFAS) ankle-hindfoot score, the visual analog scale score (VAS) of pain, the simplified symptomatology evaluation (SSE) and imaging results before the operation and at the follow-up were recorded and compared. Results: The cohort were followed-up for a mean of 63.9 months (range 24-110 months). Twenty-nine (96.7%) patients were satisfied with the curative effect. The FAOS score was improved from 53.5±6.2 preoperatively to 88.4±6.6 at the final follow-up (P<0.001). The AOFAS ankle-hindfoot scale improved from 61.6±8.2 preoperatively to 90.8±6.8 at the last follow-up (P<0.001). The VAS score decreased from 4.3±0.2 preoperative to 0.7±0.7 at the last follow-up (P<0.001). The SSE score was poor in 14 cases (46.7%), average in 16 cases (53.3%) before the operation; and it was excellent in 23 cases (76.7%), good in 6 cases (20%), average in 1 case (3.3%) at the last follow-up. Imaging examination showed cystic change cure rate was 83.3%, cartilage defects were completely infilled with repair tissue, which didn't show any signs of degeneration. However, repair tissue showed varying degrees of heterogeneous signal compared to the normal articular cartilage. Conclusion: The autograft of tibial periosteum-bone complex transplantation is a safe and feasible method for the treatment of osteochondral lesion of the talus in Hepple V type, with good mid-and-long term clinical effect.


Assuntos
Tálus , Adulto , Transplante Ósseo , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Periósteo , Resultado do Tratamento
3.
Phys Rev Lett ; 125(13): 132501, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-33034500

RESUMO

We report the first observation of two wobbling bands in ^{183}Au, both of which were interpreted as the transverse wobbling (TW) band but with different behavior of their wobbling energies as a function of spin. It increases (decreases) with spin for the positive (negative) parity configuration. The crucial evidence for the wobbling nature of the bands, dominance of the E2 component in the ΔI=1 transitions between the partner bands, is provided by the simultaneous measurements of directional correlation from the oriented states ratio and the linear polarization of the γ rays. Particle rotor model calculations with triaxial deformation reproduce the experimental data well. A value of spin, I_{m}, has been determined for the observed TW bands below which the wobbling energy increases and above which it decreases with spin. The nucleus ^{183}Au is, so far, the only nucleus in which both the increasing and the decreasing parts are observed and thus gives the experimental evidence of the complete transverse wobbling phenomenon.

4.
Phys Rev Lett ; 124(5): 052501, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32083900

RESUMO

The rare phenomenon of nuclear wobbling motion has been investigated in the nucleus ^{187}Au. A longitudinal wobbling-bands pair has been identified and clearly distinguished from the associated signature-partner band on the basis of angular distribution measurements. Theoretical calculations in the framework of the particle rotor model are found to agree well with the experimental observations. This is the first experimental evidence for longitudinal wobbling bands where the expected signature partner band has also been identified, and establishes this exotic collective mode as a general phenomenon over the nuclear chart.

5.
Phys Rev Lett ; 122(6): 062501, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30822069

RESUMO

New rotational bands built on the ν(h_{11/2}) configuration have been identified in ^{105}Pd. Two bands built on this configuration show the characteristics of transverse wobbling: the ΔI=1 transitions between them have a predominant E2 component and the wobbling energy decreases with increasing spin. The properties of the observed wobbling bands are in good agreement with theoretical results obtained using constrained triaxial covariant density functional theory and quantum particle rotor model calculations. This provides the first experimental evidence for transverse wobbling bands based on a one-neutron configuration, and also represents the first observation of wobbling motion in the A∼100 mass region.

6.
Phys Rev Lett ; 120(2): 022502, 2018 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-29376727

RESUMO

The g factor of the 56 ns half-life isomeric state in ^{128}Cs has been measured using the time-differential perturbed angular distribution method. This state is the bandhead of the positive-parity chiral rotational band, which emerges when an unpaired proton, an unpaired neutron hole, and an even-even core are coupled such that their angular momentum vectors are aplanar (chiral configuration). g-factor measurements can give important information on the relative orientation of the three angular momentum vectors. The measured g factor g=+0.59(1) shows that there is an important contribution of the core rotation in the total angular momentum of the isomeric state. Moreover, a quantitative theoretical analysis supports the conclusion that the three angular momentum vectors lie almost in one plane, which suggests that the chiral configuration in ^{128}Cs demonstrated in previous works by characteristic patterns of electromagnetic transitions appears only above some value of the total nuclear spin.

7.
Phys Rev Lett ; 116(11): 112501, 2016 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-27035296

RESUMO

Two pairs of positive-and negative-parity doublet bands together with eight strong electric dipole transitions linking their yrast positive- and negative-parity bands have been identified in ^{78}Br. They are interpreted as multiple chiral doublet bands with octupole correlations, which is supported by the microscopic multidimensionally-constrained covariant density functional theory and triaxial particle rotor model calculations. This observation reports the first example of chiral geometry in octupole soft nuclei.

8.
Phys Rev Lett ; 113(3): 032501, 2014 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-25083635

RESUMO

Three sets of chiral doublet band structures have been identified in the ^{103}Rh nucleus. The properties of the observed chiral doublet bands are in good agreement with theoretical results obtained using constrained covariant density functional theory and particle rotor model calculations. Two of them belong to an identical configuration and provide the first experimental evidence for a novel type of multiple chiral doublets, where an "excited" chiral doublet of a configuration is seen together with the "yrast" one. This observation shows that the chiral geometry in nuclei can be robust against the increase of the intrinsic excitation energy.

9.
Phys Rev Lett ; 110(17): 172504, 2013 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-23679714

RESUMO

Two distinct sets of chiral-partner bands have been identified in the nucleus 133Ce. They constitute a multiple chiral doublet, a phenomenon predicted by relativistic mean field (RMF) calculations and observed experimentally here for the first time. The properties of these chiral bands are in good agreement with results of calculations based on a combination of the constrained triaxial RMF theory and the particle-rotor model.

13.
Aliment Pharmacol Ther ; 29(11): 1155-64, 2009 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-19302265

RESUMO

BACKGROUND: Effects of octreotide on post-endoscopic retrograde cholangiopancreatography pancreatitis have been studied in many clinical trials. These trials have yielded inconclusive results. Results of more recent studies using larger doses, however, seem to be more optimistic. AIM: To examine effects of octreotide at different doses on PEP. METHODS: A comprehensive search of relevant databases, including Medline, Embase, the Cochrane Controlled Trials Register, the Cochrane Library and Science Citation Index yielded 18 randomized controlled trials (RCTs). Trials were divided into two groups according to the total dosage of octreotide: <0.5 mg (OCT1), > or =0.5 mg (OCT2). The rate of PEP was analysed using a fixed effect model. RESULTS: At doses of > or =0.5 mg, octreotide reduced the rate of PEP. In the OCT2 group, analysis revealed a statistically significant difference on PEP between the octreotide group and the controls (3.4% vs. 7.5%, pooled OR = 0.45; 95% CI: 0.28-0.73; P = 0.001, NNT = 25). In the OCT1 group, the rate of PEP was similar between patients receiving octreotide and the controls (7.2% vs. 6.0%, pooled OR = 1.23; 95% CI: 0.80-1.91; P = 0.35). CONCLUSION: Octreotide is effective in preventing PEP, but only at sufficient doses (> or =0.5 mg).


Assuntos
Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Fármacos Gastrointestinais/uso terapêutico , Octreotida/administração & dosagem , Pancreatite/prevenção & controle , Humanos , Razão de Chances , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
14.
J Phys Chem A ; 111(2): 216-22, 2007 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-17214456

RESUMO

The ground-state structures of neutral, cationic, and anionic phosphorus clusters P(n), P(n)(+), and P(n)(-) (n = 3-15) have been calculated using the B3LYP/6-311+G* density functional method. The P(n)(+) and P(n)(-) (n = 3-15) clusters with odd n were found to be more stable than those with even n, and we provide a satisfactory explanation for such trends based on concepts of energy difference, ionization potential, electron affinity, and incremental binding energy. The result of odd/even alternations is in good accord with the relative intensities of cationic and anionic phosphorus clusters observed in mass spectrometric studies.

15.
Shengzhi Yu Biyun ; 11(4): 46-54, 1991 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-12284922

RESUMO

PIP: In Zhejiang Province, China, there are 2.7 million IUD users. 90% of them use stainless steel single ring. In order to evaluate the effectiveness of the IUDs, the Provincial Family Planning Commission organized a prospective comparative study on 3 kinds of IUDs: the single ring made in Wuxi, the metal ring with plastic core made in Beijing, and the copper TCU 220c made in Tianjin. Between October 1985 and March 1986 1199 healthy women aged 20-39 who had 2 or fewer normal deliveries and without previous history of ectopic pregnancy were screened and recruited to the study. They were randomly assigned to be inserted with the IUDs. 400 women had single ring, 402 women had metal with plastic core, and 397 had TCu 220c. 8 postinsertion follow-up visits were conducted up to 3 years, and menstruations were recorded every month. During the study, 4 cases were lost to follow-up. In the single-ring group, the cumulative continuation rates at 12, 24, and 36 months were 73.4, 66.7, and 65.7% respectively. For the metal-plastic ring group, it was 80.9, 72.3, and 69.3% and for the TCu 220c group, it was 94.5, 88.4, and 83.1%, respectively. The expulsion rates among the 3 kinds of IUDs were statistically significant at 12, 24, and 36 months. The highest expulsion rates were the single ring and TCu 220c were the lowest. The pregnancy rates were highest among metal-plastic ring users and lowest among TCu 220c users. The differences were not statistically significant between single ring and metal-plastic ring users. Discontinuation due to excessive menstrual bleeding were similar among the 3 methods probably due to treatment of the users who experienced excessive bleeding. Younger women and women who experienced fewer pregnancies were found to have higher expulsion and pregnancy rates. But the occurrence of side effects such as prolonged menstrual periods, spotting, and back pain were highest among TCu 220c users. It was recommended that the more effective TCu 220c should be promoted to replace the single ring. Since different sizes of TCu IUDs have been developed, it would be possible to reduce excessive menstrual bleeding and its side effects.^ieng


Assuntos
Anticoncepção , Dispositivos Anticoncepcionais Femininos , Hemorragia , Dispositivos Intrauterinos de Cobre , Dispositivos Intrauterinos , Estudos Prospectivos , Aço Inoxidável , Ásia , Fenômenos Químicos , Química , China , Comportamento Contraceptivo , Países em Desenvolvimento , Doença , Serviços de Planejamento Familiar , Ásia Oriental , Compostos Inorgânicos , Metais , Pesquisa , Sinais e Sintomas
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