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Background To investigate the effect of bowel resection combined with fluoroscopic-assisted balloon thrombectomy for small bowel infarction caused by acute mesenteric venous thrombosis (AMVT). Methods Between June 2016 and August 2017, nine patients (seven males and two females; range, 40–73 years; mean, 55.11 ± 10.08 years) with small bowel infarction caused by AMVT underwent bowel resection combined with fluoroscopic-assisted balloon thrombectomy. The demographics, risk factors, therapeutic effect, complications, mortality, and follow-up of the study population were assessed. Results The effective rate was 100% with substantial clinical improvement in symptoms. All patients underwent small bowel resection with primary anastomosis. The length of bowel resection ranged from 60 to 170 cm (108.67 ± 35.05). In none of the cases there was surgery with second look. The patients were discharged 13–42 days (20.11 ± 8.75) after admission without perioperative complication or death. The follow-up period was 8–21 months (12.89 ± 4.65), and the follow-up rate was 100%. All patients returned to normal activities, regained lost body weight, and remained asymptomatic during the follow-up period. Conclusions The combination therapy of bowel resection and fluoroscopic-assisted balloon thrombectomy is technically feasible and may be beneficial for small bowel infarction caused by AMVT in removing a thrombus efficiently, relieving symptoms rapidly, averting second-look surgery, lowering extensive surgical resections, and improving the prognosis.

This paper extends the recent work of Shibata from static perspective to dynamic perspective, presents a differential game model of pollution abatement RD the pollution abatement R&D investment spillovers have some positive influence on optimal cooperative R&D investment while make the optimal noncooperative R&D investment decrease.

In this work, a lab-scale membrane system was developed to accommodate angular vibrations with a hollow fiber module. A series of filtration experiments were designed and implemented to investigate the effects of angular vibrations on fouling by various algae-derived foulants, including algal cells, debris, extracellular organic matter (EOM), and intracellular organic matter (IOM). The experimental results indicated the effects of angular vibrations on fouling mitigation at the frequency of 2 Hz in the following order: algal cells (~ 97.4%) > debris (~ 93.6%) > IOM (~ 81.8%) > EOM (~ 52.3%). The vibrations mainly targeted the cake layer formed by these foulants, but was ineffective for pore blocking which constituted a large portion of EOM fouling. Although the fouling rates were accelerated during the normal ultrafiltration of the combined foulants, the effects of angular vibrations continued to be impressive (67.8–92.6%). This was because the cake layer formation was the dominant fouling mechanism. Furthermore, the vibrations were found to improve the organic removal by alleviating concentration polarization. In this paper, quantitative analysis is presented to demonstrate the potential of angular vibrations to control algal fouling with the relatively low energy consumption of 0.034 mW.

In lightweight engineering, mechanical metamaterials (MMs) are suitable for additive manufacturing (AM) due to their geometry complexity. However, it is inevitable to bring about mechanical deviation and local yield for MMs infilled lightweight structures. In the current work, MMs mapped structures, named as MMs-TO-PSLs, are proposed. The design domain is divided into core-region, intermediate-region, and solid-region. Core-regions derived from topology optimization (TO) are mapped with MMs, of which the [1 0 0] orientations are aligned with the normal directions of principal stress lines (PSLs). The intermediate-regions are infilled with ribbons according to PSLs. The solid regions are allocated to stress concentrated areas. Finally, near isotropic mechanical response is achieved in core-region from anisotropic MMs, and the serious local deformation is eased. To validate such approach, the mapping strategy is carried out on a beam subjected to three-point bending. Metallic MMs-TO-PSLs and MMs infilled uniform lightweight structure are fabricated by selective laser melting (SLM). Elastoplastic simulations with ductile failure model are proposed to investigate the strengthen mechanism of MMs-TO-PSLs. Experimental and numerical results confirmed the ultimate strength of MMs-TO-PSLs can be 40% larger than conventional MMs infilled uniform structures.

The treatment for bilateral carotid stenosis (BCS) is challenging, and the optimal treatment strategy is not clear. We report our experience of treating 8 patients with BCS by simultaneous carotid endarterectomy (CEA) and carotid stenting (CAS), thereby providing an alternative for vascular surgeons.Between October 2010 and August 2014, 8 patients (5 males and 3 females; range, 53-82 years; mean, 69 ± 8.8 years) underwent simultaneous CEA and CAS in our hospital. CEA before CAS was done in 5 patients, and CAS before CEA was done in 3 patients. One patient also underwent simultaneous coronary artery bypass grafting due to unstable angina. Intraoperative transcranial Doppler ultrasonography, carotid shunts, patches, and embolic protection devices were used in all patients. Instances of hyperperfusion syndrome (HPS), hemodynamic depression, stroke, myocardial infarction (MI), and death were recorded.All patients completed the procedure. One patient developed postprocedural HPS. After systemic treatment, he recovered completely. There were no deaths, major and/or minor strokes, or MI, nor did any patient exhibit lower palsy in cranial nerves in the perioperative period (30 days) or on clinical follow-up (3 and 6 months). We observed no restenosis and no recurrent symptoms during follow-up.After careful preoperative assessment and preparation, simultaneous CEA and CAS for high-grade BCS may be considered as an alternative management strategy in carefully selected patients.

The ultrasonic-assisted water confined laser micromachining is a novel micromachining method. This paper reports the experimental studies of ultrasonic power and water layer thickness on the laser (1064 nm nanosecond pulse laser) micromachining of silicon. Besides, this reports a systematic discussion on the influence of the acoustic streaming and bubbles (induced by laser) dynamic change on the machining process. The acoustic streaming and flow pattern under different ultrasonic power application and different water layer thickness using Particle Image Velocimetry (PIV). A finite element (FE) heat transfer model was employed to gain a better understanding of the effect of the acoustic streaming velocity on the temperature field change in laser processing. The bubbles (induced by laser) dynamic behavior is observed by the high-speed camera. The results showed that the ultrasonic-assisted laser ablation can yield much higher the material removal rate than laser cutting in water without ultrasonic-assisted. Besides, the increase in the ultrasonic power helps to improve the etching efficiency but is not apparent. When the water layer thickness is 1 mm, the cutting effect is significantly different from the laser ablation in the other three water layers. Through the PIV images and simulate results, it has been found that the influence of acoustic streaming on heat transfer in laser processing is small. Through high-speed camera imaging observations, the dynamic change of bubbles is an essential mechanism for the enhanced material removal rate and affect the machining performance in this study. This study helps understand the mechanism of ultrasonic-assisted water confined laser micromachining better and promoting this technique potential application in the micromachining of hard brittle materials.

This investigation compared the effects of pre-deposited and pre-mixed powdered activated carbons (PACs) in submerged ultrafiltration membrane reactors on the distribution of extracellular organic matter (EOM) and its contribution to algal fouling during the filtration of algae-rich water. Experimental results indicate that pre-mixed PAC mitigated algal fouling, whereas pre-deposited PAC exhibited the opposite effect. The porous fouling layer in the pre-mixed case favored the retention of rejected EOM in the concentrated solution owing to a high backward migration rate. Conversely, the dense fouling layer in the pre-deposited case impeded the backward diffusion of EOM, which caused the majority of the rejected EOM to accumulate on the surface and at the bottom of the fouling layer. This difference in EOM distribution led to different cleaning efficiencies. Physical cleaning easily removed both algal cells and pre-mixed PAC from the membrane surfaces, whereas physical and chemical cleanings were both ineffective for pre-deposited PAC, owing to the stronger PAC-EOM attractive force and the NaClO-induced change in the chemical bonds of the PAC and even the membranes. Moreover, decreased algae growth rates were observed in the reactors with PAC as a result of changes in the illumination and the cake layer structure, which could further intensify the contrast between the effects of pre-deposited and pre-mixed PACs on fouling.