Individualized small bowel preparation for computed tomography enterography: A prospective randomized controlled trial.

BACKGROUND AND AIM: The study aims to evaluate the feasibility of body mass index (BMI)-based individualized small bowel preparation for computed tomography enterography (CTE). METHODS: In this prospective randomized controlled study, patients undergoing CTE were randomly assigned to the individualized group or standardized group. Those in individualized group were given different volumes of mannitol solution based on BMI (1000 mL for patients with BMI < 18.5 kg/m2, 1500 mL for patients with 18.5 kg/m2 ≤ BMI < 25 kg/m2 and 2000 mL for patients with BMI ≥ 25 kg/m2) while patients in the standardized group were all asked to consume 1500-mL mannitol solution. CTE images were reviewed by two experienced radiologists blindly. Each segment of the small bowel was assessed for small bowel image quality and disease detection rates. Patients were invited to record a diary regarding adverse events and acceptance. RESULTS: A total of 203 patients were enrolled and randomly divided into two groups. For patients with BMI < 18.5 kg/m2, 1000-mL mannitol solution permitted a significantly lower rate of flatulence (P = 0.045) and defecating frequency (P = 0.011) as well as higher acceptance score (P = 0.015), but did not affect bowel image quality and diseases detection compared with conventional dosage. For patients with BMI ≥ 25 kg/m2, 2000-mL mannitol solution provided better overall image quality (P = 0.033) but comparable rates of adverse events and patients' acceptance compared with conventional dosage. CONCLUSIONS: Individualized bowel preparation could achieve both satisfactory image quality and patients' acceptance thus might be an acceptable alternative in CTE.

A stepwise strategy integrating dynamic stress CT myocardial perfusion and deep learning-based FFRCT in the work-up of stable coronary artery disease.

OBJECTIVES: To validate a novel stepwise strategy in which computed tomography-derived fractional flow reserve (FFRCT) is restricted to intermediate stenosis on coronary computed tomography angiography (CCTA) and computed tomography myocardial perfusion imaging (CT-MPI) was reserved for vessels with gray zone FFRCT values. MATERIALS AND METHODS: This retrospective study included 87 consecutive patients (age, 58 ± 10 years; 70% male) who underwent CCTA, dynamic CT-MPI, interventional coronary angiography (ICA), and fractional flow reserve (FFR) for suspected or known coronary artery disease. FFRCT was computed using a deep learning-based platform. Three stepwise strategies (CCTA + FFRCT + CT-MPI, CCTA + FFRCT, CCTA + CT-MPI) were constructed and their diagnostic performance was evaluated using ICA/FFR as the reference standard. The proportions of vessels requiring further ICA/FFR measurement based on different strategies were noted. Furthermore, the net reclassification index (NRI) was calculated to ascertain the superior model. RESULTS: The CCTA + FFRCT + CT-MPI strategy yielded the lowest proportion of vessels requiring additional ICA/FFR measurement when compared to the CCTA + FFRCT and CCTA + CT-MPI strategies (12%, 22%, and 24%). The CCTA + FFRCT + CT-MPI strategy exhibited the highest accuracy for ruling-out (91%, 84%, and 85%) and ruling-in (90%, 85%, and 85%) functionally significant lesions. All strategies exhibited comparable sensitivity for ruling-out functionally significant lesions and specificity for ruling-in functionally significant lesions (p > 0.05). The NRI indicated that the CCTA + FFRCT + CT-MPI strategy outperformed the CCTA + FFRCT strategy (NRI = 0.238, p < 0.001) and the CCTA + CT-MPI strategy (NRI = 0.233%, p < 0.001). CONCLUSIONS: The CCTA + FFRCT + CT-MPI stepwise strategy was superior to the CCTA + FFRCT strategy and CCTA+ CT-MPI strategy by minimizing unnecessary invasive diagnostic catheterization without compromising the agreement rate with ICA/FFR. CLINICAL RELEVANCE STATEMENT: Our novel stepwise strategy facilitates greater confidence and accuracy when clinicians need to decide on interventional coronary angiography referral or deferral, reducing the burden of invasive investigations on patients. KEY POINTS: • A stepwise CCTA + FFRCT + CT-MPI strategy holds promise as a viable method to reduce the need for invasive diagnostic catheterization, while maintaining a high level of agreement with ICA/FFR. • The CCTA + FFRCT + CT-MPI strategy performed better than the CCTA + FFRCT and CCTA + CT-MPI strategies. • A stepwise CCTA + FFRCT + CT-MPI strategy allows to minimize unnecessary invasive diagnostic catheterization and helps clinicians to referral or deferral for ICA/FFR with more confidence.

The association between obesity indicators and metabolic risk factors in type-2 diabetic patients.

Rationale and objectives: Obesity, accumulation of adipose tissue, is a global disease that can lead to cardiovascular and metabolic complications. The aim of this study was to investigate the relationship between obesity indicators and metabolic risk factors in type 2 diabetes mellitus (T2DM) patients. Materials and methods: A total of 337 T2DM subjects were included in our study. The metabolic risk factors including diabetes duration, fast plasma glucose (FPG), height, weight, systolic blood pressure (SBP), diastolic blood pressure (DBP), estimated average glucose (eAG), glycated hemoglobin (HbA1c), total cholesterol (TC), high-density lipoprotein-cholesterol (HDL-c), low-density lipoprotein-cholesterol (LDL-c), triglyceride (TG), blood urea nitrogen (BUN), serum creatinine (Scr), free fatty acid (FFA), uric acid (UA), cystatin c (cysc), albumin (Alb), urinary albumin creatinine ratio (UACR) were recorded. The obesity indicators included body surface area (BSA), body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR), para-perirenal fat thickness (PRFT), total abdominal fat (TAF), subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT). The association between obesity indicators and metabolic risk factors was investigated by univariate and multivariate analysis. Results: HDL-c was independently associated with WHR and PRFT (ß = -0.126 vs. -0.214, both p < 0.05). TG and Scr were both independently associated with PRFT (ß = 0.173 vs. 0.218, both p < 0.01, respectively). UA was independently associated with BSA (ß = 0.172, p < 0.01) and PRFT (ß = 0.151, p < 0.01). cysc, Alb and UACR were independently associated with WC (ß = 0.274 vs. 0.204 vs. 0.182, all p < 0.01). Conclusion: In T2DM patients, obesity indicators were significantly associated with metabolic risk factors.

Evaluating the Impact of Intracranial Volume Correction Approaches on the Quantification of Intracranial Structures in MRI: A Systematic Analysis.

BACKGROUND: In neuroscience, accurately quantifying individual brain regions in large cohorts is a challenge. Differences in intracranial structures can suggest functional differences, but they also reflect the effects of other factors. However, there is currently no standardized method for the correction of intracranial structure measurements. PURPOSE: To identify the optimal method to counteract the influence of total intracranial volume (TIV) and gender on the measurement of intracranial structures. STUDY TYPE: Prospective. POPULATION/SUBJECTS: One hundred forty-one healthy adult volunteers (70 male, mean age 21.8 ± 1.7 years). FIELD STRENGTH/SEQUENCE: T1-weighted 3D gradient-echo sequence at 3.0 T. ASSESSMENT: A radiologist with 5 years of work experience screened the raw images to exclude poor-quality images. Freesurfer then performed automated segmentation to obtain measurements of intracranial structures. Male-only, female-only, and TIV-matched sub-samples were created separately. Comparisons between the original data and these sub-samples were used to assess the effects of gender and TIV. Comparison the consistency between TIV-matched sample and corrected data that corrected by four methods: Proportion method, power-corrected proportion method, covariate regression method, and residual method. STATISTICAL TESTS: Cohen's d for examining group distribution disparities, t-tests for probing mean differences, correlation coefficients to assess the relationships between intracranial substructure measurements and TIV. Multiple comparison corrections were applied to the results. RESULTS: The correlation coefficients between TIV and the volumes of intracranial structures ranged from 0.033 to 0.883, with an average of 0.467. Thirty significant volume differences were found among 36 structures in the original sample, while no differences were observed in the TIV-matched sample. Among the four correction methods, the residual method had highest consistency (similarity 94.4%) with the TIV-matched group. DATA CONCLUSION: The variation in intracranial structure sizes between genders was largely attributable to TIV. The residual method offers a more accurate and effective approach for correcting the effects of TIV on intracranial structures. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 1.

Review on Progress of Lamellar Orientation Control in Directionally Solidified TiAl Alloys.

TiAl alloys have excellent high-temperature performance and are potentially used in the aerospace industry. By controlling the lamellar orientation through directional solidification (DS) technology, the plasticity and strength of TiAl alloy at room temperature and high temperatures can be effectively improved. However, various difficulties lie in ensuring the lamellar orientation is parallel to the growth direction. This paper reviews two fundamental thoughts for lamellar orientation control: using seed crystals and controlling the solidification path. Multiple specific methods and their progress are introduced, including α seed crystal method, the self-seeding method, the double DS self-seeding method, the quasi-seeding method, the pure metal seeding method, and controlling solidification parameters. The advantages and disadvantages of different methods are analyzed. This paper also introduces novel ways of controlling the lamellar orientation and discusses future development.

Cardiac computed tomography based analysis of mitral annulus, coronary sinus and left circumflex artery in patients with mitral regurgitation: Implications for transcatheter mitral annuloplasty techniques.

INTRODUCTION: CT imaging analysis of mitral annulus (MA), coronary sinus (CS) and left circumflex artery (LCX) is critical to transcatheter mitral annuloplasty (TMA), which, however, is scantly reported. We aimed to comprehensively assess MA, CS and LCX anatomy and geometry in mitral regurgitation (MR) based on 3-D reconstruction of cardiac CT images. METHODS: Patients with primary or secondary MR and patients without MR were recruited and underwent cardiac CT examination. MR severity was evaluated by echocardiography. 3-D reconstruction of cardiac CT images was done by the Mimics Research 21.0 software. A MA-centered two dimensional coordinate system, a CS plane, a MA plane and a series of auxiliary planes along the posterior MA were created for the measurement of parameters defining MA, CS and LCX anatomy and geometry during the cardiac cycle. RESULTS: The secondary MR group had a significantly higher MA perimeter index than the other two groups during the cardiac cycle. The CS diameters at most sites, and the posterior MA radian were substantially greater in the two MR groups. Distances between the CS and MA at some locations were significant different among the three groups. The secondary MR group had a significantly smaller CS-MA plane angle than the other two groups during systole, and than control group during diastole. The site where the CS crossed LCX was pinpointed. CONCLUSION: The comprehensive information from this study may help improve the results of TMA and enhance the design of devices for a better annuloplasty effect.

The value of cardiac CT in the diagnosis of unroofed coronary sinus syndrome.

BACKGROUND: Unroofed coronary sinus syndrome (UCSS) is a rare cardiovascular malformation with nonspecific clinical manifestations that easily causes misdiagnosis and missed diagnosis. The aim of this study is to present the different features of UCSS by various CCT (cardiac CT) postprocessing techniques and evaluate the diagnostic advantages of CCT. METHODS: 9 UCSS patients who were diagnosed by imaging and undergone both CCT and transthoracic echocardiography (TTE) were included in this study, and their CCT images were reviewed. The UCSS images were classified by multiplanar reformations, maximum intensity projection, volume rendering and cinematic rendering. The size of CS roof defect was also measured. RESULTS: Only 4 of 9 CCT confirmed UCSS patients were detected by TTE (4/9, 44.4%), the sensitivity of TTE was lower compared to CCT by Fisher's exact test (P < 0.05). UCSS was classified according to the Kirklin and Barratt Boyes's method, including 1 case was classified as type I, 4 cases as type II, 1 case as type III, 2 cases as type IV, 1 case as type V (variant type), and TTE was undiagnosed in all type III-V patients. Additionally, CCT showed 12 extra malformations in these patients, only 5 of them were found by TTE (5/12, 41.7%), and TTE missed all extracardiac malformations. The mean size of CS roof defect was 3.04 ± 1.57 cm. CONCLUSIONS: CCT with various postprocessing technologies has excellent value in diagnosing and differentiating subtypes of UCSS, measuring size of coronary sinus defect, describing accompanying cardiovascular abnormalities.

Neural Regulations in Tooth Development and Tooth-Periodontium Complex Homeostasis: A Literature Review.

The tooth-periodontium complex and its nerves have active reciprocal regulation during development and homeostasis. These effects are predominantly mediated by a range of molecules secreted from either the nervous system or the tooth-periodontium complex. Different strategies mimicking tooth development or physiological reparation have been applied to tooth regeneration studies, where the application of these nerve- or tooth-derived molecules has been proven effective. However, to date, basic studies in this field leave many vacancies to be filled. This literature review summarizes the recent advances in the basic studies on neural responses and regulation during tooth-periodontium development and homeostasis and points out some research gaps to instruct future studies. Deepening our understanding of the underlying mechanisms of tooth development and diseases will provide more clues for tooth regeneration.

Fluorine Effect for Improving Oxidation Resistance of Ti-45Al-8.5Nb Alloy at 1000 °C.

In-depth analyses of the anti-oxidation behavior and structure of γ-TiAl alloys are of great significant for their maintenance and repair in engineering applications. In this work, fluorine-treated Ti-45Al-8.5Nb alloys and fluorine-treated oxidized specimens with artificial defects were prepared by isothermal oxidation treatment at 1000 °C. Several characterization methods, including SEM, EDS, XRD and TEM, were used to evaluate the surface microstructure of the fluorine-treated Ti-45Al-8.5Nb alloys and fluorine-treated oxidized specimens with artificial defects. The results indicate that the fluorine promoted the formation of an outer protective film of Al2O3, which significantly improved the oxidation resistance. The microcracks of oxidized specimens with the artificial defects provided a rapid diffusion passage for Ti and O elements during the 1000 °C/2 h isothermal oxidation treatment process, resulting in the quick growth of TiO2 toward the outside. The fine Al2O3 constituted a continuous film after the 1000 °C/100 h isothermal oxidation treatment. In particular, Al2O3 particles grew toward the substrate, which was ascribed to the good oxidation resistance and adhesion. These results may provide an approach for the repair of protective oxide film on the surface of blades and turbine disks based on γ-TiAl alloys.

Switching Diagram of Core-Shell FePt/Fe Nanocomposites for Bit Patterned Media.

In the current work, a core-shell type exchange coupled composite structure was constructed by micromagnetic simulation with a phase FePt core and an iron shell. Four types of switching loops with magnetic domain structure evolution were demonstrated. Based on the simulation results, a switching type diagram was constructed, which displays various hysteresis loops as a function of core radius and shell thickness. Furthermore, the effects of switching type and composite structure on the coercivity and remanent magnetization were predicted and discussed. This finding indicates that core-shell type FePt/Fe composite structure film has a large advantage in designing exchange-coupled bit patterned media to realize high-density storage devices at the nanoscale.

Human Resource Planning and Configuration Based on Machine Learning.

Human resources are the core resources of an enterprise, and the demand forecasting plays a vital role in the allocation and optimization of human resources. Starting from the basic concepts of human resource forecasting, this paper employs the backpropagation neural network (BPNN) and radial basis function neural network (RBFNN) to analyze human resource needs and determine the key elements of the company's human resource allocation through predictive models. With historical data as reference, the forecast value of current human resource demand is obtained through the two types of neural networks. Based on the prediction results, the company managers can carry out targeted human resource planning and allocation to improve the efficiency of enterprise operations. In the experiment, the actual human resource data of a certain company are used as the experimental basic samples to train and test the two types of machine learning tools. The experimental results show that the method proposed in this paper can effectively predict the number of personnel required and can support the planning and allocation of human resources.

Airway foreign body caused by pepper inhalation 7 years previously retrieved under conscious sedation with spontaneous respiration: a case report.

A 26-year-old man who had inhaled a dried pepper 7 years previously was admitted to our hospital for repeated coughing with yellow sputum and occasional hemoptysis. A thoracic high-resolution computed tomography scan revealed a foreign body at the proximal end of the right lower bronchus. We attempted to remove the foreign body by flexible bronchoscopy, but this was unsuccessful because the foreign body fell deeper into the bronchus. After a multidisciplinary team meeting, the foreign body was successfully extracted by bronchoscope suction and forceps under conscious sedation with spontaneous respiration. We avoided rigid bronchoscopy and traumatic surgery, thus decreasing the patient's risk and cost. We herein share our successful experience with this case.

Ti-40Al-10Nb-10Cr Porous Microfiltration Membrane with Hierarchical Pore Structure for Particulate Matter Capturing from High-Temperature Flue Gas.

TiAl-based porous microfiltration membranes are expected to be the next-generation filtration materials for potential applications in high-temperature flue gas separation in corrosive environments. Unfortunately, the insufficient high-temperature oxidation resistance severely limits their industrial applications. To tackle this issue, a Ti-40Al-10Nb-10Cr porous alloy was fabricated for highly effective high-temperature flue gas purification. Benefited from microstructural changes and the formation of two new phases, the Ti-40Al-10Nb-10Cr porous alloy demonstrated favorable high-temperature anti-oxidation performance with the incorporation of Nb and Cr high-temperature alloying elements. By the separation of a simulated high-temperature flue gas, we achieved an ultra-high PM-removal efficiency (62.242% for PM<2.5 and 98.563% for PM>2.5). These features, combined with our experimental design strategy, provide a new insight into designing high-temperature TiAl-based porous materials with enhanced performance and durability.

Knowledge of Hyperemic Myocardial Blood Flow in Healthy Subjects Helps Identify Myocardial Ischemia in Patients With Coronary Artery Disease.

BACKGROUNDS: Dynamic CT myocardial perfusion imaging (CT-MPI) allows absolute quantification of myocardial blood flow (MBF). Although appealing, CT-MPI has not yet been widely applied in clinical practice, partly due to our relatively limited knowledge of CT-MPI. Knowledge of distribution and variability of MBF in healthy subjects helps in recognition of physiological and pathological states of coronary artery disease (CAD). OBJECTIVES: To describe the distribution and normal range of hyperemic MBF in healthy subjects obtained by dynamic CT-MPI and validate whether it can accurately identify functional myocardial ischemia when the cut-off value of hyperemia MBF is set to the lower limit of the normal range. MATERIALS AND METHODS: Fifty-one healthy volunteers (age, 38 ± 12 years; 15 men) were prospectively recruited. Eighty patients (age, 58 ± 10 years; 55 men) with suspected or known CAD who underwent interventional coronary angiography (ICA) examinations were retrospectively recruited. Comprehensive CCTA + dynamic CT-MPI protocol was performed by the third - generation dual-source CT scanner. Invasive fractional flow reserve (FFR) measurements were performed in vessels with 30-90% diameter reduction. ICA/FFR was used as the reference standard for diagnosing functional ischemia. The normal range for the hyperemic MBF were defined as the mean ± 1.96 SD. The cut-off value of hyperemic MBF was set to the lower limit of the normal range. RESULTS: The global hyperemic MBF were 164 ± 24 ml/100 ml/min and 123 ± 26 ml/100 ml/min for healthy participants and patients. The normal range of the hyperemic MBF was 116-211 ml/100 ml/min. Of vessels with an ICA/FFR result (n = 198), 67 (34%) were functionally significant. In the per-vessel analysis, an MBF cutoff value of <116 ml/100 ml/min can identify myocardial ischemia with a diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of 85.9% (170/198), 91.0% (61/67), 83.2 % (109/131), 73.5% (61/83), and 94.8% (109/115). CT-MPI showed good consistency with ICA/FFR in diagnosing functional ischemia, with a Cohen's kappa statistic of 0.7016 (95%CI, 0.6009 - 0.8023). CONCLUSION: Recognizing hyperemic MBF in healthy subjects helps better understand myocardial ischemia in CAD patients.

Lattice Phase Field Model for Nanomaterials.

The lattice phase field model is developed to simulate microstructures of nanoscale materials. The grid spacing in simulation is rescaled and restricted to the lattice parameter of real materials. Two possible approaches are used to solve the phase field equations at the length scale of lattice parameter. Examples for lattice phase field modeling of complex nanostructures are presented to demonstrate the potential and capability of this model, including ferroelectric superlattice structure, ferromagnetic composites, and the grain growth process under stress. Advantages, disadvantages, and future directions with this phase field model are discussed briefly.

Ti leaching differences during acid leaching of coal gangue based on different thermal fields.

Two thermal fields, namely, microwave assistance and traditional heating, were used in this study to extract valuable Ti mineral resources from industrial solid waste (i.e., coal gangue) through acid leaching. Moreover, leaching extraction differences between the two thermal fields were analyzed. The leaching optimization experiment in different thermal fields revealed that the microwave power, acid-to-gangue ratio, and microwave radiation time under the microwave thermal field were 800 W, 1.5, and 1.25 h, respectively; the Ti leaching rate in coal gangue under these conditions reached 81.25%. By contrast, the heating temperature, acid-to-gangue ratio, and heating time under the traditional thermal field were 170 °C, 1.4, and 4 h, respectively; the Ti leaching rate in coal gangue under these conditions reached 91.83%. Characterization analysis demonstrated that the phase compositions of Ti in acid-leached coal gangue under the microwave thermal field were Ti2H2(SO4)4·5H2O and H2Ti3O7, whereas those under the traditional thermal field were H2TiO3 and Ti2(SO4)3. Ti-containing compounds were detected from acid leaching residue under the microwave thermal field, whereas those under the traditional thermal field were mainly silicon oxide and calcium sulfate. The SEM graph of acid leaching residue also reflected microstructural differences in acid leaching residue under the microwave and traditional thermal fields. This study provides new perspectives in the highly efficient and comprehensive utilization of Ti mineral resources in coal gangue.

Refinement of Nanoporous Copper with Poly(vinyl alcohol) During Dealloying Amorphous Mg65Cu25Y10 Precursors.

Ultrafine nanoporous copper (UNP Cu) with a characteristic pore size of about 12 nm and a ligament size of about 14 nm was fabricated from amorphous Mg65Cu25Y10 precursor alloys after dealloying in a 0.1 M H2SO4 solution modified by poly(vinyly alcohol) polymers with a molecular weight of 105000 g/mol (PVA-124). The suppression of the surface diffusion from PVA-124 reduced the size of the nanopores and ligaments to 20 nm when the concentration of the added PVA-124 exceeded 0.1 g L-1. When the concentration of the added PVA-124 exceeded 2 g L-1, PVA-124 triggered the polymerization process. The resultant polymer surface layer on the fcc Cu ligaments was shown to reduce the rate of selective dissolution. It was also shown that extending the immersion time resulted in a suppression of coarsening. The introduction of PVA-124 polymer into acids resulted in a higher viscosity of the dealloying solutions, particularly when the concentration of PVA-124 was higher than 1.0 g L-1. This viscosity was shown not only to reduced rate of diffusion of Cu adatoms in PVA-124 solutions, but also forced the accumulation of Cu adatoms to form small scale UNP Cu.

Friction Weldability of a High Nb Containing TiAl Alloy.

The friction weldability of Ti-45Al-8.5Nb-0.2W-0.2B-0.02Y alloy has been investigated by optimizing process parameters and analyzing the microstructures and tensile properties of the joints. The as-cast alloy with a nearly lamellar (NL) microstructure and the as-forged alloys with a duplex (DP) microstructure have been successfully welded. All the joints have a severe deformation zone (SDZ) and a transition zone (TZ) between the parent metal (PM) and SDZ. SDZ, showing a biconcave lens geometry, has a maximum thickness of hundreds of micrometers at the periphery. TZ is hundreds of micrometers thick. All SDZs have a fine-grained DP microstructure with a grain size of a few micrometers. For the joint of the as-cast alloy, the TZ consists of deformed lamellar colonies as the major constituent and partially recrystallized grains as the minor constituent. For the joint of the as-forged alloy, the TZ is similar to both the PM and SDZ, showing a DP microstructure. The grain size, volume fraction of γ grains, and the remnant lamellar colonies all increase with the distance from the SDZ. All joints presented perfect metallurgical bonding. The strengths of the joints are higher than those of the corresponding PMs. This indicates that the studied alloy has good friction weldability.

Medical Thoracoscopy-Assisted Argon Plasma Coagulation Combined with Electrosurgical Unit for the Treatment of Refractory Pneumothorax in Elderly Patients.

PURPOSE: This study aims to compare the effects and prognosis of medical thoracoscopy-assisted argon plasma coagulation (APC) combined with electrosurgical unit (ESU) surgery, video-assisted thoracic surgery (VATS), and pleurodesis surgery, in providing appropriate treatment for elderly refractory pneumothorax patients. METHODS: Patients with refractory pneumothorax aged over 65 years were divided into three groups: APC combined with ESU (N = 20), VATS (N = 26), and pleurodesis (N = 24). Data on demographic characteristics, lung function evaluation, and short- and long-term prognoses were collected. RESULTS: Following surgery, compared with the APC-ESU and pleurodesis groups, patients in the VATS group demonstrated poor short-term prognoses, with high pleural effusion drainage levels and high visual analog scores (VAS; P <0.05). After the surgery, St. George's Respiratory Questionnaire (SGRQ) scores in the pleurodesis group were slightly elevated, whereas SGRQ scores in both the APC-ESU and VATS groups demonstrated a continual decrease. Finally, medical resource consumption analysis demonstrated a significant difference in hospitalization costs among the three groups; the VATS group being the most expensive. CONCLUSION: Medical thoracoscopy-assisted APC combined with ESU is a safe, effective, and affordable treatment for elderly patients with refractory pneumothorax.

Asynchronous Evolution of Nanoporous Silver on Dual-Phase Ag⁻Sn Alloys by Potentiostatic Dealloying in Hydrochloric Acid Solution.

Evolution behavior of the nanoporous architectures has been investigated via potentiostatic electrochemical dealloying of dual-phase AgxSn100-x (x = 20, 30, 40 at.%) alloys, which consist of ß-Sn and ε-Ag3Sn phases with different volume fractions in 1.2 M HCl solution. The results show that the open-circuit potentials and corrosion potentials of dual-phase Ag-Sn alloys are determined by the less noble ß-Sn phases rather than chemical compositions of the Ag-Sn precursor alloys. The potentiodynamic polarization curves show that the anodic dissolution of Ag-Sn alloys is divided into two stages including the first preferential dissolution of ß-Sn phases and secondary dealloying of ε-Ag3Sn phases, which is associated with the order of the nanoporous evolution. Nanoporous silver (NPS) can be fabricated by potentiostatic dealloying of dual-phase Ag-Sn alloys in HCl solution. The dealloying of two phases is asynchronous: The less noble ß-Sn phases are preferentially etched to generate the larger pores, and then the more noble ε-Ag3Sn phases are dealloyed to form the finer nanoporous structure. The significant surface diffusion of Ag adatoms at the applied potential higher than the pitting potential of ε-Ag3Sn phases during the dealloying results in the coarsening of nanoporous ligaments with a time dependence of d(t) ∝ t0.1. The fractions and the difference in electrochemical stabilities of the ß-Sn and ε-Ag3Sn phases in dual-phase AgxSn100-x (x = 20, 30, 40 at.%) precursor alloys determines the final nanoporous structure.