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1.
Opt Express ; 32(6): 9468-9485, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38571181

RESUMO

It is widely recognized that light exhibits a wave-particle duality. However, the explanation for the photonic spin Hall effect (PSHE) primarily relies on the wave nature of light as dictated by Maxwell's Equations. There is a lack of exploration into the particle nature of light in this regard. In this context, we offer a fresh interpretation of the PSHE from the perspective of particle nature of light. For the out-of-plane PSHE, the spin shifts result from the macroscopic manifestation of the conservation of spin-orbital angular momentum of one photon. For the in-plane PSHE, the spin shifts arise from the spread of in-plane wavevector. Based on the wave nature of light, we also obtain the same spin shifts, confirming the consistency of the wave-particle duality of light. Furthermore, we find that the spin shifts of the PSHE are not the overall displacement of photons with the same handedness, but the outcome of coherent superposition among photons of the same handedness. These discoveries further enhance our comprehension of the fundamental nature of the PSHE.

2.
Opt Express ; 30(9): 14112-14120, 2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35473162

RESUMO

Generally, when an arbitrary polarized light beam is reflected or refracted from an isotropic interface, the spin splitting in photonic spin Hall effect (SHE) shows asymmetry properties. In this paper, we theoretically propose a phase compensation scheme to achieve the transformation from asymmetric spin splitting to symmetric spin splitting in photonic SHE. We experimentally acquire the spin splitting after phase compensation in the case of a 45 degrees linear polarized Gaussian light beam totally internally reflected from a prism-air interface. Particularly, whether or not phase compensation, the transverse shift of total barycenter of reflected field [i.e., the Imbert-Fedorov (IF) shift] does not change. These findings can solve this problem that asymmetric spin splitting cannot be observed by weak measurements.

3.
BMC Gastroenterol ; 16: 7, 2016 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-26772979

RESUMO

BACKGROUND: In pancreaticobiliary maljunction (PBM), the sphincter of Oddi can not control bile and pancreatic juice flow, which may lead to two-way reflux of bile and pancreatic juice, thus causing chronic inflammation, thickening, fibrosis and metaplasia of the common bile duct wall. These pathophysiological changes have been linked to disruption of the epithelium barrier in the common bile duct. We hypothesized that the expression of tight junction-associated proteins may be dysregulated in the common bile duct in PBM. In the current study, we sought to analyze the expression of tight junction-associated proteins in the common bile duct epithelium of pediatric patients with PBM. METHODS: Specimens of the common bile duct were collected from 12 pediatric patients with PBM and 10 non-PBM controls. The expression of the tight junction-associated proteins occludin and claudin-1 in the epithelium was examined by immunohistochemistry. The Image-Pro Plus v. 6.0 image analysis software was used to calculate the mean qualifying score (MQS) of imunostained sections of common bile duct epithelium. Total protein extracts of common bile duct were analyzed by Western blotting assays to examine expression of occludin, claudin-1 and myosin light chain kinase (MLCK). Spearman correlation analysis was used to analyze the relation between MLCK and occludin, MLCK and claudin-1. RESULTS: Immunostained sections of the common bile duct epithelium showed significantly higher MQS in pediatric patients than controls for occludin (44.11 ± 13.82 vs. 11.30 ± 9.58, P = 0.0034) and claudin-1 (63.44 ± 23.59 vs. 46.10 ± 7.84, P = 0.0384). Western blotting also showed significantly higher expression of occludin, claudin-1 and MLCK in the common bile duct of patients than of controls (P = 0.0023, 0.0015, 0.0488). Spearman correlation analysis showed that MLCK expression correlated positively with the expression of occludin (r s = 0.61538, P = 0.0032) and claudin-1 (r s = 0.7972, P = 0.0019). CONCLUSIONS: Occludin and claudin-1 are up-regulated in the common bile duct epithelium of pediatric PBM patients. MLCK may be involved in the process of up-regulation of the tight junction-associated proteins in PBM.


Assuntos
Ductos Biliares/anormalidades , Claudina-1/metabolismo , Ducto Colédoco/metabolismo , Quinase de Cadeia Leve de Miosina/metabolismo , Ocludina/metabolismo , Ductos Pancreáticos/anormalidades , Estudos de Casos e Controles , Criança , Pré-Escolar , Epitélio/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Lactente , Masculino , Regulação para Cima
4.
Pediatr Int ; 58(9): 881-6, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26774009

RESUMO

BACKGROUND: The aim of this study was to develop a mouse model and further assess the pathological changes associated with the expression of p38mitogen-activated protein kinase (p38MAPK) in intussusception. METHODS: Sixty-two adult Balb/C mice were used. A longitudinal incision was made in the middle rectus muscle in the body cavity. The ileum was intussuscepted into the colon. Measurements were taken at the onset of intussusception and at 5, 15, 30, 60, and 120 min. Mucosal impairment was assessed on microscopy. Ten of the intussuscepted mice were used as an ischemia-reperfusion (I/R) model. Immunohistochemistry was used to assess expression of p38MAPK in the I/R model and pediatric patients specimens of intussusception. RESULTS: The intussusception model was successfully established in 46 mice. After 15 min, vascular compromise became visible in these 46 mice. Over time, vascular function worsened. There were significant differences in microscopy injury score in the intestinal mucosa between the 15 min and 30 min groups (P = 0.0006), 30 min and 60 min groups (P = 0.0046), and the 60 min and 120 min groups (P = 0.0050). There was no significant difference between the 5 min and 15 min groups (P = 0.0597). p38MAPK was expressed strongly in pediatric specimens of intussusception. Immunostained sections of intestinal epithelium had significantly higher mean quick score for p38MAPK in the intussusception I/R model group than in the intussusception group and controls (P = 0.0130). On each two-group comparison there was a significant difference between groups (all P < 0.01; Fig. ). CONCLUSIONS: The present mouse model can be used to assess the dynamic pathological changes associated with intussusception. I/R is associated with upregulation of p38MAPK in intussusception.


Assuntos
Intestino Delgado/diagnóstico por imagem , Intussuscepção/enzimologia , Proteínas Quinases p38 Ativadas por Mitógeno/biossíntese , Animais , Modelos Animais de Doenças , Feminino , Imuno-Histoquímica , Intestino Delgado/enzimologia , Intussuscepção/diagnóstico , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Microtomografia por Raio-X
5.
Heliyon ; 8(11): e11146, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36353179

RESUMO

State of charge (SOC) of ultracapacitor plays an important role in the energy management optimization of hybrid energy storage system for electric vehicles. In addition to the perfection of the model and the SOC estimation algorithm, the parameter identification method and temperature factor should also be considered. In this paper, an ultracapacitor test platform is established, the characteristic parameters of ultracapacitor at full temperature range are obtained. This paper uses the forgetting factor recursive least squares algorithm (FFRLS) to identify the parameters of the second-order equivalent circuit model of ultracapacitor online. The extended Kalman filter (EKF) algorithm is used to estimate the SOC of ultracapacitor cell. The results show that: (1) FFRLS algorithm can identify R 0 , R 1 , R 2 , C 1 , and C 2 values of ultracapacitor at full temperature range. Under the hybrid pulse power characterization working condition, the average mean absolute error between the estimated voltage and the actual voltage is about 0.0132 V. (2) EKF algorithm has a good adaptability to estimate SOC of ultracapacitor under different temperatures and working conditions. The SOC estimation error under different working conditions is low. From the perspective of mean square error, the estimation error at -20 °C is the lowest. (3) FFRLS and EKF joint estimation algorithm with good robustness and reliability can be used to estimate the SOC of ultracapacitor under different temperatures and working conditions. This study can provide a useful guidance for the parameter identification and SOC estimation of ultracapacitor for electric vehicle at different temperatures.

6.
Medicine (Baltimore) ; 97(15): e0435, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29642213

RESUMO

Percutaneous kyphoplasty (PKP) surgery is generally accepted as a minimally invasive treatment for osteoporotic vertebral compression fractures (OVCFs). However, hidden blood loss (HBL) caused by this procedure is usually disregarded. This study aimed to investigate the amount of HBL and its influencing factors after PKP surgery.A total of 160 patients were retrospectively examined from January 2014 to January 2016, and their clinical and radiological data were recorded and analyzed. Preoperative and postoperative hematocrit (Hct) and hemoglobin (Hb) levels were also documented. HBL was calculated using Gross formula. Different factors, including gender, age, bone mineral density (BMD), number of fracture levels, hypertension, diabetes mellitus, operative time, percentage of vertebral height loss, percentage of vertebral height restoration, and cement leakage, were examined. Multivariate linear regression analysis was performed to elucidate the related clinical or radiological factors of HBL.A total of 122 patients with 169 levels were eligible for inclusion in the study. The mean HBL was 279 ± 120 mL, and the postoperative Hb loss was 8.2 ±â€Š3.9 g/L. Multivariate linear regression analysis revealed that HBL was positively associated with operative time (P = .000), percentage of vertebral height loss (P = .037), and percentage of vertebral height restoration (P = .000). By contrast, HBL was not associated with gender (P = .874), age (P = .148), BMD (P = .134), number of fracture levels (P = .079), hypertension (P = .259), diabetes mellitus (P = .495), and cement leakage (P = .975). The postoperative incidence of anemia significantly increased by 39.3% compared with that of the preoperative incidence (χ = 21.432, P = .000).For patients with OVCFs, the amount of HBL after PKP is much larger than that observed perioperatively. Operative time, percentage of vertebral height loss, and percentage of vertebral height restoration are influencing factors of HBL.


Assuntos
Perda Sanguínea Cirúrgica/fisiopatologia , Fraturas por Compressão/sangue , Fraturas por Compressão/cirurgia , Hematócrito , Hemoglobinometria , Cifoplastia/efeitos adversos , Fraturas da Coluna Vertebral/sangue , Fraturas da Coluna Vertebral/cirurgia , Idoso , Anemia Ferropriva/sangue , Anemia Ferropriva/terapia , Volume Sanguíneo/fisiologia , Densidade Óssea/fisiologia , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Estudos Retrospectivos , Fatores de Risco
7.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 31(6): 677-682, 2017 06 15.
Artigo em Zh | MEDLINE | ID: mdl-29798648

RESUMO

Objective: To determine the feasibility, safety, and efficacy of common pedicle screw placement under direct vision combined with dome shaped decompression via small incision for double segment thoracolumbar fracture with nerve injury. Methods: A retrospective analysis was performed on the clinical data of 32 patients with double segment thoracolumbar fracture with nerve injury undergoing common pedicle screw placement under direct vision combined with dome shaped decompression via small incision between November 2011 and November 2015 (combined surgery group), and another 32 patients undergoing traditional open pedicle screw fixation surgery (traditional surgery group). There was no significant difference in gender, age, cause of injury, time of injury-to-surgery, injury segments and Frankel classification of neurological function between two groups ( P>0.05). The length of soft tissue dissection, the operative time, the blood loss during surgery, the postoperative drainage, the visual analogue scale (VAS) of incision after surgery, and recovery of neurological function after surgery were evaluated. Results: All cases were followed up 9 to 12 months (mean, 10.5 months) in combined surgery group, and 8 to 12 months (mean, 9.8 months) in traditional surgery group. The length of soft tissue dissection, the operative time, the blood loss during surgery, the postoperative drainage, and the postoperative VAS score in the combined surgery group were significantly better than those in the traditional surgery group ( P<0.05). Dural rupture during surgery and pedicle screw pulling-out at 6 months after surgery occurred in 2 cases and 1 case of the combined surgery group; dural rupture during surgery occurred in 1 case of the traditional surgery group. The X-ray films showed good decompression, and fracture healing; A certain degree of neurological function recovery was achieved in two groups. Conclusion: Common pedicle screw placement under direct vision combined with dome shaped decompression via small incision can significantly reduce iatrogenic trauma and provide good nerve decompression. Therefore, it is a safe, effective, and minimally invasive treatment method for double segment thoracolumbar fracture with neurological injury.


Assuntos
Parafusos Pediculares , Fraturas da Coluna Vertebral/cirurgia , Feminino , Fixação Interna de Fraturas , Humanos , Vértebras Lombares , Masculino , Estudos Retrospectivos , Vértebras Torácicas , Resultado do Tratamento
8.
Food Sci Biotechnol ; 25(1): 165-171, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-30263253

RESUMO

Effects of anthocyanins from purple sweet potato (APSP) against the fungal growth of Geotrichum candidum and Candida albicans were assessed. Response surface methodology was applied for optimization of proportions of sodium benzoate, potassium sorbate, and APSP. Optimum concentrations against G. candidum were 0.300 mg/mL of sodium benzoate, 0.290mg/mL of potassium sorbate, and 13.9mg/mL of APSP. Optimum concentrations against C. albicans were 0.380 mg/mL of sodium benzoate, 0.240 mg/mL of potassium sorbate, and 3.56 mg/mL of APSP. APSP exhibited enhanced antifungal properties in the presence of food preservatives.

9.
Saudi Med J ; 36(10): 1156-62, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26446324

RESUMO

OBJECTIVES: To conduct a meta-analysis and investigate the diagnostic value of 64-slice computed tomography (CT) angiography for diagnosing coronary artery disease (CAD) in patients. METHODS: A comprehensive literature search from March 2005 to August 2014 was performed on the following databases: Cochrane Library; Medline; EmBase; PubMed; and BioMed Central database. As a reference standard, studies that assessed 64-slice CT angiography in detecting coronary artery stenosis (CAS) with invasive coronary angiography were included. Coronary artery stenosis was defined as ≥50% diameter stenosis. Diagnostic value was determined by pooling sensitivity, specificity, positive likelihood ratio (PLR) and negative likelihood ratio (NLR) values at segment-level analysis. Diagnostic accuracy was undertaken using area under the curve (AUC) value and summary receiver operating characteristic (SROC) curves. Publication bias was examined by Deek's funnel plot asymmetry test. RESULTS: Eight studies were included in the analysis, enrolling a total of 579 patients (7,407 segment coronary vessels). At segment-level, pooled sensitivity value was 90% (95% confidence interval [CI]: 83-95%), specificity was 91% (95% CI: 61-98%), PLR value was 9.7 (95% CI: 1.8-53.3), and NLR value was 0.11 (95% CI: 0.05-0.22) for CAS. Optimal cut-off point of sensitivity was 90%, and specificity under the SROC curve was 91%. The AUC value was 0.94. CONCLUSION: The 64-slice CT angiography is a reliable tool for detection of CAD when using a cut-off of more than or equal to 50% diameter stenosis in elderly population.


Assuntos
Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Estenose Coronária/diagnóstico por imagem , Tomografia Computadorizada Multidetectores , Humanos , Curva ROC , Sensibilidade e Especificidade
10.
Zhonghua Er Ke Za Zhi ; 52(1): 41-5, 2014 Jan.
Artigo em Zh | MEDLINE | ID: mdl-24680407

RESUMO

OBJECTIVE: To investigate the clinical value of MRI examination in congenital anorectal malformation (CARM). METHOD: Forty-four cases with operatively proved anorectal malformation from May 2008 to May 2012 in the authors' hospital were reviewed. Of the 44 cases, 25 were males and 19 females, their age ranged from 1 day to 2 years. MRI was performed in all patients. RESULT: Of all 44 cases, 15 cases had high imperforate anus (34%), rectum blind end were above PC line, the distance of rectum blind end and anus nest was (29.12 ± 2.35) mm; 8 cases had median imperforate anus (18%), rectum blind ends were near PC line, the distance of rectum blind end and anus nest was (18.98 ± 2.21) mm; 21 cases had low imperforate anus (48%), rectum blind ends were below PC line, the distance of rectum blind end and anus nest was (7.54 ± 1.08) mm. Twenty-five cases with fistula in 44 cases were confirmed by rectal angiography and surgery, accounting for 57%. In 13 cases with fistula, the lesion could be clearly demonstrated on MRI, in the remaining 12 cases with fistula, the lesion could not be visualized clearly or no image development occurred on MRI. Of all 44 cases, 1 case had tethered cord with filum terminale lipoma, 1 case had tethered cord, 2 cases had syringomyelia, 1 case had right kidney agenesis, 1 case had hydrocele. In 44 cases of multi-planar MRI imaging could clearly show the perianal muscles developmental situation, 36 cases had perianal muscles dysplasia, amd showed levator ani muscle, puborectalis and anal sphincter asymmetry, muscle belly slim. CONCLUSION: MRI examination has a high clinical value in CARM diagnosis, can help accurately judge the anal atresia type, display the presence and running of most of the fistula, and diagnose perianal muscle development and other systems malformations, finally provide a reliable diagnostic basis for surgical program and prognostic assessment.


Assuntos
Canal Anal/anormalidades , Anus Imperfurado/diagnóstico , Imageamento por Ressonância Magnética , Reto/anormalidades , Anormalidades Múltiplas , Canal Anal/cirurgia , Anus Imperfurado/complicações , Anus Imperfurado/cirurgia , Pré-Escolar , Feminino , Fístula/epidemiologia , Fístula/etiologia , Humanos , Lactente , Recém-Nascido , Masculino , Períneo/patologia , Reto/cirurgia , Estudos Retrospectivos , Fístula Urinária/epidemiologia , Fístula Urinária/etiologia
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