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1.
Artículo en Inglés | MEDLINE | ID: mdl-38995769

RESUMEN

OBJECTIVE: This study aimed to evaluate the clinical characteristics and features of conventional ultrasound (CUS) and contrast-enhanced ultrasound (CEUS) in differentiating between renal urothelial carcinomas (RUC) and endophytic clear cell renal cell carcinomas (EccRCC). METHODS: A total of 72 RUCs and 120 EccRCCs confirmed by pathology were assessed retrospectively. Both CUS and CEUS were performed within 4 weeks before the surgery. Logistic regression analyses were used to select statistically significant variables of clinical, CUS, and CEUS features for the differentiation of RUC and EccRCC. Sensitivity (SEN), specificity (SPE), and the area under the receiver-operating characteristic curve (AUC) were assessed for diagnostic performance. Inter- and intra-observer agreements of CUS and CEUS features were evaluated using the intra-class correlation coefficient(ICC). RESULTS: Multiple logistic regression analysis demonstrated that clinical (age >50 years old and hematuria), CUS (size <4.0 cm, hypo-echogenicity, irregular shape, hydronephrosis) and CEUS (absence of non-enhancement area, iso- /hypo-enhancement in cortical phase and absence of rim-like enhancement) features were independent factors for RUC diagnosis. When combining clinical characters with CUS and CEUS features into an integrated diagnostic criterion, the AUC reached 0.917 (95% CI 0.873-0.961), with a sensitivity of 95.8% and specificity of 87.5%. ICC ranged from 0.756 to 0.907 for inter-observer agreement and 0.791 to 0.934 for intra-observer agreement for CUS and CEUSfeatures. CONCLUSIONS: The combination of clinical features of age and hematuria with imaging features of CUS and CEUS can be useful for the differentiation between RUC and EccRCC.

2.
Materials (Basel) ; 14(22)2021 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-34832221

RESUMEN

To investigate the brittle creep failure process of rock material, the time-dependent properties of brittle rocks under the impact of homogeneity are analyzed by the numerical simulation method, RFPA-Creep (2D). Deformation is more palpable for more homogeneous rock material under the uniaxial creep loading condition. At a low stress level, diffusion creep may occur and transition to dislocation creep with increasing applied stress. The law for increasing creep strain with the homogeneity index under a constant confined condition is similar to the uniaxial case, and dislocation creep tends to happen with increasing confining pressure for the same homogeneity index. The dilatancy index reaches its maximum at a high stress level when rock approaches failure, and the evolution of the dilatancy index with the homogeneity index under the same confining pressure is similar to the uniaxial case and is more marked than that under the unconfined condition. Both uniaxial and triaxial creep failure originate from the ductile damage accumulation inside rock. The dominant shear-type failure is exhibited by uniaxial creep and the conventional compression case presents the splitting-based failure mode. Under confining pressure, the creep failure pattern is prone to shear, which is more notable for the rock with higher homogeneity.

3.
Bioinspir Biomim ; 16(5)2021 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-34225261

RESUMEN

Octopus suckers that possess the ability to actively control adhesion through muscle actuation have inspired artificial adhesives for safe manipulation of thin and delicate objects. However, the design of adhesives with fast adhesion switching speed to transport cargoes in confined spaces remains an open challenge. Here, we present an untethered magnetic adhesive pad combining the functionality of fast adhesion switching and remotely controlled locomotion. The adhesive pad can be activated from low-adhesion state to high-adhesion state by near infrared laser within 30 s, allowing to fulfill a high-throughput task of retrieving and releasing objects. Moreover, under the guidance of external magnetic field, the proposed pad is demonstrated to transport thin and fragile electronic components across a tortuous path, thus indicating its potential for dexterous delivery in complex working environments.


Asunto(s)
Adhesivos , Locomoción , Electrónica , Fenómenos Magnéticos , Fenómenos Físicos
4.
Artículo en Chino | MEDLINE | ID: mdl-24506996

RESUMEN

OBJECTIVE: To investigate the feasibility of Matrix-Assisted Laser Desorption-Ionization Time of Flight Mass Spectrometry (MALDI-TOF-MS) , according to the genetic test of non-syndromic hearing loss (NSHL), and check using the direct sequencing. METHODS: Peripheral blood was collected from 454 NSHL patients. DNA samples were extracted and 20 loci of the four common disease-causing genes were analysed by MALDI-TOF-MS, including GJB2 (35delG, 167delT, 176_191del16, 235delC, 299_300delAT ), GJB3 (538C→T, 547G→A), SLC26A4 (281C→T, 589G→A, IVS7-2A→G, 1174A→T, 1226G→A, 1229C→T, IVS15+5G→A, 1975G→C, 2027T→A, 2162C→T, 2168A→G), and mitochondrial 12S rRNA (1494C→T, 1555A→G). Direct sequencing was also used to analyse the aforementioned 20 loci in order to validate the accuracy of MALDI-TOF-MS. RESULTS: Among the 454 patients, 166 cases (36.56%) of disease-causing mutations were detected, which included 69 cases (21.15%) of GJB2 gene mutation, four cases (0.88%) of GJB3 gene mutation, 64 cases (14.10%) of SLC26A4 gene mutation, and three cases (0.66%) of mitochondrial 12S rRNA gene mutation. Moreover, the results obtained from direct sequencing and MALDI-TOF-MS were consistent, and the results showed that the two methods were consistent. CONCLUSIONS: The MALDI-TOF-MS detection method was designed based on the hearing loss-related mutation hotspots seen in the Chinese population, and it has a high detection rate for NSHL related mutations. In comparison to the conventional detection methods, MALDI-TOF-MS has the following advantages: more detection sites, greater coverage, accurate, high throughput and low cost. Therefore, this method is capable of satisfying the needs of clinical detection for hearing impairment and it is suitable for large-scale implementation.


Asunto(s)
Pruebas Genéticas , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Adolescente , Adulto , Pueblo Asiatico/genética , Niño , Preescolar , Conexina 26 , Conexinas , Sordera/genética , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Mutación , Análisis de Secuencia por Matrices de Oligonucleótidos , Adulto Joven
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