Application of Computed Tomography Angiography in Preoperative Diagnosis of Coarctation of Aorta and Evaluation of Aortic Dilatation in Infants.

OBJECTIVE: To evaluate the occurrence of aortic dilatation and its associated predictors with coarctation of the aorta (CoA) in infants using multi-slice computed tomography (MSCT). METHODS: The clinical data of 47 infantile patients with CoA diagnosed by MSCT and 28 infantile patients with simple ventricular septal defect were analyzed retrospectively. Aortic diameters were measured at six different levels, and aortic sizes were compared by z score. The coarctation site-diaphragm ratio was used to describe the degree of narrowing. Relevant clinical data were collated and analyzed. RESULTS: The dilation rate and z score of the ascending aorta in the severe CoA group were significantly higher than those in the mild CoA group (11 [52.38%] vs. 21 [80.77%], P=0.038 and 2.00 ± 0.48 vs. 2.36 ± 0.43, P=0.010). Pearson's correlation analysis found that the z score of the ascending aorta was negatively correlated with the coarctation site-diaphragm ratio value (r=-0.410, P=0.004). A logistic retrospective analysis found that an increased degree of coarctation was an independent predictor of aortic dilatation (adjusted odds ratio 0.002; 95% confidence interval 0.00-0.819; P=0.043). The z score of the ascending aorta in the severe CoA group was significantly higher than that in the ventricular septal defect group (P<0.05). CONCLUSION: Most infants with CoA can also have significant dilatation of the ascending aorta, and the degree of this dilatation is related to the degree of coarctation. Assessment of aortic diameter and related malformations by MSCT can predict the risk of aortic dilatation in infants with CoA.

Decisional regret and impacts on quality of life following genitourinary reconstruction for neurogenic bladder: A comparison between acquired and congenital spinal cord injury.

INTRODUCTION: Patient expectations and baseline health are important drivers of outcomes following major genitourinary reconstructive surgery for neurogenic bladder (NGB). Differences in expectations and quality of life (QoL) improvements among different populations with NGB remain insufficiently explored in the literature. OBJECTIVE: To compare decisional regret (DR) and urinary-related QoL (UrQoL) in patients undergoing urinary diversion for NGB arising from spinal cord injury of acquired (A-SCI) and congenital (C-SCI) etiologies. We hypothesize that patients with A-SCI have higher expectations of improvement in QoL following surgery when compared with C-SCI, which may lead to higher DR and decreased UrQoL, postoperatively. DESIGN: In this cross-sectional survey study, we compared A-SCI to C-SCI in terms of DR, UrQoL, and postoperative changes in self-reported physical health, mental health, and pain using validated patient-reported outcome measures. SETTING: Participants were enrolled from a quaternary care institution via mail and MyChart. PARTICIPANTS: The A-SCI group consistied of 17 patients with traumatic spinal cord injury the C-SCI group was composed of 20 patients with spina bifida. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: The Decisional Regret Scale, Short form- Qualiveen (SF-Qualiveen), and Patient-reported outcomes measurement Information system-10 (PROMIS-10) Global Health surveys. RESULTS: The A-SCI group displayed poorer preoperative physical health than the C-SCI cohort, but absolute postoperative changes in this score, along with mental health score and pain level, were not significant after adjusting for baseline scores and follow-up time. SF-Qualiveen scores revealed significantly worse impact of NGB in UrQoL for A-SCI than for C-SCI when adjusted for other factors. No differences in DR were seen between the groups. CONCLUSIONS: Patients with A-SCI demonstrate lower self-reported baseline physical health compared with patients with C-SCI, which may have implications in setting patient expectations when undergoing urinary diversion. In this small cohort, we found a milder self-reported postoperative impact of NGB in UrQoL in patients with C-SCI.

An Obesity-Centric Approach with and Without Anti-Obesity Medications Compared to the Usual-Care Approach to Management of Patients with Obesity and Type 2 Diabetes in an Employer Setting: A Pragmatic Randomized Controlled Trial (EMPOWER-T2D).

INTRODUCTION: This study aimed to compare weight loss and glycated hemoglobin (HbA1c)-reduction effects of two obesity-centric, weight-loss management approaches (with or without anti-obesity medication) versus usual glucose-centric care in patients with obesity and type 2 diabetes. METHODS: Single-center, randomized, open-label, 3-armed, parallel-group, pragmatic, noninferiority trial, July 2020 to August 2022. Adults enrolled in the Cleveland Clinic Employee Health Plan (body mass index [BMI] ≥ 30 kg/m2, type 2 diabetes diagnosis, HbA1c > 7.5%) were randomized to usual glucose-centric management ("Usual-Care" group) or one of two obesity-centric management strategies: participation in a weight management program plus anti-obesity medication ("WMP + AOM" group), or WMP participation without anti-obesity medication ("WMP-Only" group). Primary endpoints were changes in weight and HbA1c, baseline to month 12. RESULTS: Due to enrollment and retention challenges, largely related to COVID-19, only 74/300 planned participants were randomized and the study was terminated early. Participants were predominantly female (59%), median (interquartile range [IQR]) age 53.5 (47, 60) years, 68% white, with baseline median (IQR) BMI and HbA1c of 37.4 (34.2, 42.7) kg/m2 and 8.8% (7.9%, 10.4%), respectively. At month 12, mean (90% confidence interval [CI]) percentage weight change in the Usual-Care, WMP-Only, and WMP + AOM groups was - 4.5% (- 6.5%, - 2.5%), - 6.7% (- 8.7%, - 4.7%), and - 8.7% (- 10.7%, - 6.8%), respectively; mean (90% CI) HbA1c change was - 1.7% (- 2.1%, - 1.2%), - 2.2% (- 2.7%, - 1.8%), and - 2.2% (- 2.6%, - 1.7%), respectively. WMP + AOM was superior to Usual-Care for weight change (P = 0.02); both WMP + AOM and WMP-Only were noninferior (P ≤ 0.01) to Usual-Care for change in HbA1c. CONCLUSIONS: Including anti-obesity medication was associated with superior weight loss with noninferior HbA1c reductions, warranting further evaluation in larger study populations of obesity-focused approaches to type 2 diabetes management. Graphical abstract available for this article. TRIAL REGISTRATION: ClinicalTrials.gov NCT03799198.

Surgical versus medical management of patients with primary hyperaldosteronism and indeterminate adrenal vein sampling: A 10-year experience of the Cleveland Clinic.

In patients with primary hyperaldosteronism (PA), adrenal vein sampling (AVS) can identify patients suitable for unilateral adrenalectomy. However, in AVS with an indeterminate aldosterone-to-cortisol lateralization (ACL) ratio of 3.0-4.0, clinical guidance is unclear. The authors screened all patients undergoing AVS at the Cleveland Clinic from October 2010 to January 2021 and identified 18 patients with indeterminate ACL results. Ten underwent adrenalectomy and eight continued medical management. The surgical group was younger (58.5 vs. 68 years, p = .17), and more likely to have a unilateral imaging adrenal abnormality (90% vs. 38%, p = .043) and a lower contralateral suppression index (0.63 vs. 1.1, p = .14). Post-treatment, the surgical group had a significant reduction in diastolic blood pressure (-5.5 mmHg, p = .043) and aldosterone (4.40 vs. 35.80 ng/mL, p = .035) and required fewer anti-hypertensive medications (2 vs. 3, p = .015). These findings may support the benefit of adrenalectomy in a select group of patients with indeterminate ACL.

Inflammatory myofibroblastic tumor of the heart in an older woman with paroxysmal atrial fibrillation: a case report and review of the literature.

Inflammatory myofibroblastic tumors (IMTs) of the heart are rarely observed in the eldly. We report a case involving an elderly woman with an IMT situated on the right atrial wall. The tumor was fully excised. The patient had a smooth recovery post-surgery and remained free of recurrence for three years.

Real-World Surgical and Endoscopic Recurrence Based on Risk Profiles and Prophylaxis Utilization in Postoperative Crohn's Disease.

BACKGROUND & AIMS: Preoperative risk stratification may help guide prophylactic biologic utilization for the prevention of postoperative Crohn's disease (CD) recurrence; however, there are limited data exploring and validating proposed clinical risk factors. We aimed to explore the preoperative clinical risk profiles, quantify individual risk factors, and assess the impact of biologic prophylaxis on postoperative recurrence risk in a real-world cohort. METHODS: In this multicenter retrospective analysis, patients with CD who underwent ileocolonic resection (ICR) from 2009 to 2020 were identified. High-risk (active smoking, ≥2 prior surgeries, penetrating disease, and/or perianal disease) and low-risk (nonsmokers and age >50 y) features were used to stratify patients. We assessed the risk of endoscopic (Rutgeert score, ≥i2b) and surgical recurrence by risk strata and biologic prophylaxis (≤90 days postoperatively) with logistic and time-to-event analyses. RESULTS: A total of 1404 adult CD patients who underwent ICR were included. Of the high-risk factors, 2 or more ICRs (odds ratio [OR], 1.71; 95% CI, 1.13-2.57), active smoking (OR, 1.73; 95% CI, 1.17-2.53), penetrating disease (OR, 1.41; 95% CI, 1.02-1.94), and history of perianal disease alone (OR, 1.99; 95% CI, 1.42-2.79) were associated with surgical but not endoscopic recurrence. Surgical recurrence was lower in high-risk patients receiving prophylaxis vs not (10.2% vs 16.7%; P = .02), and endoscopic recurrence was lower in those receiving prophylaxis irrespective of risk strata (high-risk, 28.1% vs 37.4%; P = .03; and low-risk, 21.1% vs 38.3%; P = .002). CONCLUSIONS: Clinical risk factors accurately illustrate patients at risk for surgical recurrence, but have limited utility in predicting endoscopic recurrence. Biologic prophylaxis may be of benefit irrespective of risk stratification and future studies should assess this.

How should preoperative examinations be chosen for infants with a ventricular septal defect: transthoracic echocardiography, cardiac CTA, or a combination of these two technologies?

OBJECTIVE: To evaluate the accuracy of transthoracic echocardiography (TTE) and cardiac computed tomography angiography (CTA) in detecting the size and location of ventricular septal defects (VSD) in infants. METHODS: Data from 258 infants diagnosed with VSD between January 2020 and December 2022 were retrospectively analyzed. All infants underwent both TTE and cardiac CTA. The accuracy of these imaging modalities was assessed by comparing their findings with intraoperative observations of VSD size and location. RESULTS: Intraoperatively, the average VSD size was 6.1 ± 2.5 mm. The defects were classified as committed VSD (Type 1) in 45 patients, noncommitted VSD (Type 2) in 198 patients, inlet VSD (Type 3) in 12 patients, and muscular VSD (Type 4) in 3 patients. Echocardiography estimated the average VSD size at 5.6 ± 2.7 mm, with 42 patients identified as Type 1, 203 as Type 2, 10 as Type 3, and 3 as Type 4. Cardiac CTA estimated the average size at 5.9 ± 3.2 mm, with 48 patients identified as Type 1, 196 as Type 2, 11 as Type 3, and 3 as Type 4. The accuracy rates of TTE and cardiac CTA in diagnosing VSD location were 98.1% and 98.8%, respectively. A survey of surgeons indicated that 80% believe both TTE and cardiac CTA are essential preoperative evaluations. CONCLUSIONS: TTE accurately diagnoses the size and location of VSD, while cardiac CTA serves as a valuable complementary method to TTE. Most surgeons advocate for the combined use of these examinations for preoperative assessment.

Solitary Fibrous Tumor of Breast and Axilla: Clinicopathological Profile of Five Tumors With Comparison of Risk Stratification Models.

Introduction: Solitary fibrous tumor (SFT) is a fibroblastic tumor with malignant potential that is underpinned by a recurrent inv12(q13q13)-derived NAB2::STAT6 fusion. Breast and axilla are uncommon locations for this entity. Methods: Records of two academic institutions were electronically searched for breast and axillary SFTs. Clinical and pathologic data were reviewed. Literature review for breast or axillary SFTs was performed. Present study and previously reported tumors were stratified using five SFT risk models: original and modified Demicco metastatic risk, Salas local recurrence risk, Salas metastatic risk, and Thompson local recurrence risk. Results: Five patients with breast or axillary SFT were identified. Median age was 49 years, and median follow-up (available for four patients) was 82 months. Three patients showed no evidence of disease, and one developed recurrence. Literature review identified 58 patients with breast or axillary SFT. Median age was 54 years, and median follow-up (available for 35 patients) was 24 months. Thirty-one patients showed no evidence of disease, three developed recurrence, and one developed metastasis. Original and modified Demicco models and Thompson model showed the highest sensitivity; original and modified Demicco models and Salas metastatic risk model demonstrated the highest specificity. Kaplan-Meier models were used to assess recurrence-free probability (RFP). Original and modified Demicco models predicted RFP when stratified by "low risk" and "moderate/intermediate and high risk" tumor, though sample size was small. Conclusions: While many SFTs of breast and axilla remain indolent, a subset may develop recurrence and rarely metastasize. The modified Demicco risk model demonstrated optimal performance characteristics.

Using Revolution™ CT Angiography to Assess Complex Coarctation of the Aorta in Infants and Its Association with a Prolonged Postoperative Cardiac ICU Stay.

OBJECTIVE: To investigate the accuracy of aortic dimensions measured by Revolution™ computed tomography (CT) in infants with complex coarctation of the aorta (CoA) and to further analyze the utility of the degree of CoA in predicting the risk of prolonged postoperative cardiac intensive care unit stay. METHODS: A total of 30 infants with complex CoA who underwent surgical correction from January 2020 to July 2022 were retrospectively enrolled. General demographic data, preoperative imaging, and perioperative outcomes were collected. Univariate and multivariate analyses were performed to investigate predictors of prolonged postoperative cardiac intensive care unit stay, and the reliability of the CT measurements was assessed by the intraclass correlation coefficient. RESULTS: All infants were divided into a mild or severe CoA group. The duration of mechanical ventilation and cardiac intensive care unit stay in the mild CoA group were significantly lower than those in the severe CoA group. After multivariate analysis, we found that the degree of CoA and age at surgery were significant predictors of prolonged postoperative cardiac intensive care unit stay. The intraclass correlation coefficient between CT measurements and intraoperative measurements was between 0.937 and 0.975, and the measurement results had good reliability. CONCLUSION: CT angiography can provide a comprehensive and accurate preoperative evaluation of aortic dimensions measured in infants with complex CoA. The degree of CoA is an independent risk factor for prolonged postoperative cardiac intensive care unit stay in infants with complex CoA.

Comparison of Myopia Progression among Myopic Children with Intermittent Exotropia and No Strabismus.

SIGNIFICANCE: Myopia is a highly prevalent condition in the pediatric population that is commonly comorbid with intermittent exotropia. Our study found a trend toward significance in the reduction of myopia progression with strabismus correction surgery. Further investigations characterizing the interaction between myopia and strabismus may help inform future management guidelines. PURPOSE: This study describes and compares myopic progression in the pediatric population with and without intermittent exotropia and its interaction with corrective strabismus surgery. METHODS: This study analyzed a retrospective cohort of 1239 pediatric myopic patients who were evaluated by pediatric ophthalmologists and optometrists at a tertiary care center from 2012 to 2020. The main outcome measures were the trends in refractive error over time in those with and without intermittent exotropia as well as trends in those who did and did not undergo strabismus surgery. RESULTS: A total of 275 patients (22%) were identified to have intermittent exotropia, and 12 (4.4%) from this group underwent surgical correction in the study period. No statistically significant difference was identified in myopic progression between those with intermittent exotropia and those without strabismus, and no difference was found in mean annual spherical equivalent change between intermittent exotropia patients who did not undergo surgery compared with those who did. CONCLUSIONS: Pediatric myopic patients generally experience progression in the condition for several years independent of concurrent intermittent exotropia. Corrective strabismus surgery was not found to alter the natural history of myopia in children, although a reduction in myopic progression in surgically treated patients trended toward significance. Increases in the prevalence of different treatment strategies will necessitate further studies to determine best practices for this population.

Using Revolution™ CT Angiography to Assess Complex Coarctation of the Aorta in Infants and Its Association with a Prolonged Postoperative Cardiac ICU Stay

ABSTRACT Objective: To investigate the accuracy of aortic dimensions measured by Revolution™ computed tomography (CT) in infants with complex coarctation of the aorta (CoA) and to further analyze the utility of the degree of CoA in predicting the risk of prolonged postoperative cardiac intensive care unit stay. Methods: A total of 30 infants with complex CoA who underwent surgical correction from January 2020 to July 2022 were retrospectively enrolled. General demographic data, preoperative imaging, and perioperative outcomes were collected. Univariate and multivariate analyses were performed to investigate predictors of prolonged postoperative cardiac intensive care unit stay, and the reliability of the CT measurements was assessed by the intraclass correlation coefficient. Results: All infants were divided into a mild or severe CoA group. The duration of mechanical ventilation and cardiac intensive care unit stay in the mild CoA group were significantly lower than those in the severe CoA group. After multivariate analysis, we found that the degree of CoA and age at surgery were significant predictors of prolonged postoperative cardiac intensive care unit stay. The intraclass correlation coefficient between CT measurements and intraoperative measurements was between 0.937 and 0.975, and the measurement results had good reliability. Conclusion: CT angiography can provide a comprehensive and accurate preoperative evaluation of aortic dimensions measured in infants with complex CoA. The degree of CoA is an independent risk factor for prolonged postoperative cardiac intensive care unit stay in infants with complex CoA.

Accuracy and image quality of wide-detector revolution CT angiography combined with prospective ECG-triggered CT angiography in the diagnosis of congenital aortic arch anomalies in Chinese children.

Objective: To explore the accuracy and image quality of wide-detector revolution CT angiography combined with prospective ECG-triggered CT angiography in the diagnosis of congenital aortic arch anomalies in Chinese children. Methods: From January 2020 to July 2022, the clinical data of 57 children with congenital aortic arch anomalies confirmed by surgery were collected. All patients underwent CT angiography (CTA) with Revolution CT and transthoracic echocardiography (TTE) before the operation. The accuracy of CTA and TTE in the diagnosis of aortic arch anomalies was compared with the surgical results. Result: The diagnostic sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of CTA and TTE for congenital aortic arch anomalies (including intracardiac and extracardiac structural abnormalities) were 92.2% and 85.5%, 99.4%, and 99.1%, 97.4% and 95.6%, 98.1% and 96.9%, and 97.2% and 95.2%, respectively. Regarding extracardiac structural malformations, the sensitivity of CTA was 100%, whereas that of TTE was 78.6% (P < 0.001). Regarding intracardiac structural malformations, the sensitivity of CTA was 84.5%, whereas that of TTE was 92.5% (P < 0.001). Regarding satisfaction with the images in aortic arch anomalies, surgeons noted that the CTA images were more useful for diagnosis and operation planning compared with TTE. Conclusion: Wide-detector revolution CT angiography combined with prospective ECG triggering can be routinely used to assess congenital aortic arch anomalies, providing adequate image quality and high diagnostic accuracy. However, limitations in the identification of intracardiac structural abnormalities are noted.

Computed tomography angiography assessment of the degree of simple coarctation of the aorta and its relationship with surgical outcome: A retrospective analysis.

Objective: To investigate the correlation between the degree of aortic coarctation and surgical prognosis in infants with simple coarctation of the aorta (CoA) using computed tomography angiography (CTA). Methods: This study was a retrospective study. Twenty-seven infants with simple CoA who underwent surgical correction from January 2020 to June 2022 were enrolled. Aortic diameters were measured at five different levels and normalized to Z scores based on the square root of body surface area. The relevant data were collected and analyzed, and the predictors associated with surgical outcome were determined. Results: Patients were divided into the mild CoA group and the severe CoA group according to the severity of coarctation. The mechanical ventilation duration and the length of ICU stay in the mild CoA group were significantly lower than those in the severe CoA group. Multiple linear regression analyses revealed that the degree of aortic coarctation was a significant risk factor for a prolonged postoperative ICU stay. In addition, gestational age and age at operation were risk factors for a prolonged postoperative ICU stay. Correlation analysis showed that the degree of aortic coarctation correlated with the Z scores of the ascending aorta and postcoarctation aorta. Conclusion: The degree of the CoA is an important predictor of surgical outcomes in infants with simple CoA and was significantly correlated with the ascending aorta and postcoarctation aorta Z scores. Therefore, preoperative CTA should be routinely performed to assess the degree of aortic coarctation and better identify risk factors.

Rural Acoustic Landscape Analysis Based on Segmentation and Extraction of Spectral Image Feature Information.

Spectrogram is an image that can record voice information, which can be analyzed by analyzing the received image. Spectrograms are used in mechanical fault diagnosis systems to answer questions such as the location, type, and extent of the fault. It is the main tool for analyzing vibration parameters. In actual use, there are three types of spectrograms, namely linear amplitude spectrum, logarithmic amplitude spectrum, and self-power spectrum. The ordinate of the linear amplitude spectrum has a clear physical dimension and is the most commonly used. In this paper, the feature extraction information of rural acoustic landscape is mainly carried out through spectral images, which can effectively improve the segmentation efficiency, ensure the integrity of information, and determine the feasibility of establishing acoustic landscape in rural areas. This article aims to study the analysis of rural acoustic landscape in Guilin, Guangxi, based on the segmentation and extraction of spectral image feature information, through the segmentation and extraction of spectral image feature information, and then analyze the advantages and disadvantages of rural acoustic landscape. In this article, the Gabor wavelet filtering method is proposed to filter and analyze the spectral image. Through the detailed analysis of the insect and bird calls of the forest community near the village of Guilin, Guangxi, finally, the satisfaction and attention of the rural villagers to the acoustic landscape are investigated. The experimental results show that the sound of insects and birds reaches the maximum in spring and the minimum in autumn and winter. Moreover, the attention of rural villagers to acoustic landscape is also very high, with satisfaction of 87.12% and attention of 92.68%.

Evaluation of the aorta in infants with simple or complex coarctation of the aorta using CT angiography.

Objective: To assess aortic dilatation and determine its related factors in infants with coarctation of the aorta (CoA) by using computed tomography angiography (CTA). Methods: The clinical data of 55 infantile patients with CoA diagnosed by CTA were analyzed retrospectively. Aortic diameters were measured at six different levels and standardized as Z scores based on the square root of body surface area. The results of simple and complex CoA were compared. Univariate and multivariate logistic regression were used to analyze the effects of sex, age, hypertension, degree of coarctation, CoA type, bicuspid aortic valve (BAV), and other factors related to aortic dilatation. Results: In total, 52 infant patients with CoA were analyzed, including 22 cases of simple CoA and 30 cases of complex CoA. The ascending aorta of the infants in the simple CoA group and the complex CoA group were dilated to different degrees, but the difference was not statistically significant (50.00% vs. 73.33%, P = 0.084, and 2.05 ± 0.40 vs. 2.22 ± 0.43 P = 0.143). The infants in the complex CoA group had more aortic arch hypoplasia than those in the simple CoA group (33.33% vs. 9.09%, P = 0.042). Compared to the ventricular septal defect (VSD) group, the Z score of the ascending aorta in the CoA group was significantly higher than that in the VSD group (P = 0.023 and P = 0.000). A logistic retrospective analysis found that an increased degree of coarctation (CDR value) was an independent predictor of ascending aortic dilatation (adjusted OR = 0.002; P = 0.034). Conclusion: Infants with simple or complex CoA are at risk of ascending aortic dilatation, and the factors of ascending aortic dilatation depend on the degree of coarctation. The risk of aortic dilatation in infants with CoA can be identified by CTA.

[Chemical constituents from Pachysandra terminalis].

To study chemical constituents from Pachysandra terminalis. By repeated column chromatography, including silica gel, Toyopearl HW-40, and preparative HPLC, four new (14) and one known (5) compounds were isolated and purified. On the basis of spectral data analysis, the structure of isolated compounds were elucidated as follow: 2-methyl-3-methylenepentane-1, 2, 5-triol (1), 4-methyl-3-methylenepentane-1, 2, 5-triol (2), 4-methyl-3-methylenepentane-1, 2, 5-triol-5-O-beta-D-glucopyranoside (3), 4-methyl-3-methylenep- entane-1, 2, 5-triol-1-O-beta-D-glucopyranoside (4), (7S, 8R, 8' R)-(+)-lariciresinol-9-O-beta-D-glucopyrano-side (5). Compound 5 was isolated from this genus for the first time.

[Experimental study on the bonding strength between FCVA film and titanium].

PURPOSE: To study the bonding strength between the FCVA (filtered cathode vacuum arc) film and the titanium substrate. METHODS: According to the Engineer Manual of Germany (VDI3198), the indentation test was applied to evaluate the bonding strength between the FCVA film and the titanium substrate. The structure of the FCVA film and the interface between the film and the substrate were observed by means of scanning electron microscope(SEM). RESULTS: The fracture pattern of the film was classified as HF3 at the load of 400N, the bonding strength was enough between the FCVA film and the titanium substrate. SEM photograph showed the thickness of the FCVA film was about 1.2µm equably and the film bonded to the substrate well. CONCLSION: The bonding strength between the FCVA film and the titanium substrate was enough to meet clinical demand.

Biosorption of copper and lead ions by waste beer yeast.

Locally available waste beer yeast, a byproduct of brewing industry, was found to be a low cost and promising adsorbent for adsorbing copper and lead ions from wastewater. In this work, biosorption of copper and lead ions on waste beer yeast was investigated in batch mode. The equilibrium adsorptive quantity was determined to be a function of the solution pH, contact time, beer yeast concentration, salt concentration and initial concentration of copper and lead ions. The experimental results were fitted well to the Langmuir and Freundlich model isotherms. According to the parameters of Langmuir isotherm, the maximum biosorption capacities of copper and lead ions onto beer yeast were 0.0228 and 0.0277 mmol g(-1) at 293 K, respectively. The negative values of the standard free energy change (DeltaG degrees ) indicate spontaneous nature of the process. Competitive biosorption of two metal ions was investigated in terms of sorption quantity. The amount of one metal ion adsorbed onto unit weight of biosorbent (q(e)) decreased with increasing the competing metal ion concentration. The binding capacity for lead is more than for copper. Ion exchange is probably one of the main mechanism during adsorptive process.

Biosorption of copper(II) and lead(II) from aqueous solution by chaff in a fixed-bed column.

In this article, the ability of chaff to adsorb heavy metal ions from aqueous solution was investigated in a fixed-bed column. The effect of important parameters, such as the value of pH, the flow rate, the influent concentration of solution and the effect of coexistence ions, was studied. Also the adsorption/desorption recycles of chaff were shown, and the results indicated that chaff could be recycled to remove heavy metal ions. The Thomas model was applied to adsorption of copper and lead at different flow rate and different influent concentration to predict the breakthrough curves and to determine the characteristic parameters of the column useful for process design. The model was found suitable for describing the biosorption process of the dynamic behavior of the chaff column. All the results suggested that chaff as adsorbent to removal heavy metal ions from solution prove efficient, and the rate of biosorption process is speedy. Furthermore, the efficiency of adsorption is high. When the flow rate was 3.6 ml min(-1) and the influent concentration of copper and lead was 14.82 mg l(-1) and 50.12 mg l(-1) respectively, the equilibrium adsorption biomass reached 1.98 mg g(-1) and 6.72 mg g(-1), respectively. The competitive adsorption for lead and copper was studied. Moreover the total adsorbing capability of chaff did not decrease when there were both copper(II) and lead(II) in solution.