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The increasing concerns on uranium and rare earth metal ion pollution in the environment require sustainable strategies to remove them from wastewater. The present study reports an eco-friendly approach to convert a kind of protein-rich biomass, brewer''s spent grain (BSG), into effective biosorbents for uranyl and rare earth metal ions. The employed method reduces the energy consumption by performing the hydrothermal treatment at a significantly lower temperature (150 °C) than conventional hydrothermal carbonization. In addition, with the aid of the Maillard reaction between carbohydrates and proteins forming melanoidins, further activation processes are not required. Treatment at 150 °C for 16 h results in an altered biosorbent (ABSG) with increased content of carboxyl groups (1.46 mmol g−1) and a maximum adsorption capacity for La3+, Eu3+, Yb3+ (pH = 5.7) and UO22+ (pH = 4.7) of 38, 68, 46 and 221 mg g−1, respectively. Various characterization methods such as FT-IR, 13C CP/MAS NMR, SEM-EDX and STA-GC-MS analysis were performed to characterize the obtained material and to disclose the adsorption mechanisms. Aside from oxygen-containing functional groups, nitrogen-containing functional groups also contribute to the adsorption. These results strongly indicate that mild hydrothermal treatment of BSG could be applied as a greener, low-cost method to produce effective adsorbents for uranyl and rare earth metal ion removal.

Effective biosorbent ABSG is obtained via hydrothermal treatment of BSG at low temperature without activation, minimizing energy consumption and environmental impact.  相似文献   
3.
Future left ventricular assist devices (LVADs) are expected to respond to the physiologic need of patients; however, they still lack reliable pressure or volume sensors for feedback control. In the clinic, echocardiography systems are routinely used to measure left ventricular (LV) volume. Until now, echocardiography in this form was never integrated in LVADs due to its computational complexity. The aim of this study was to demonstrate the applicability of a simplified ultrasonic sensor to fit an LVAD cannula and to show the achievable accuracy in vitro. Our approach requires only two ultrasonic transducers because we estimated the LV volume with the LV end‐diastolic diameter commonly used in clinical assessments. In order to optimize the accuracy, we assessed the optimal design parameters considering over 50 orientations of the two ultrasonic transducers. A test bench was equipped with five talcum‐infused silicone heart phantoms, in which the intra‐ventricular surface replicated papillary muscles and trabeculae carnae. The end‐diastolic LV filling volumes of the five heart phantoms ranged from 180 to 480 mL. This reference volume was altered by ±40 mL with a syringe pump. Based on the calibrated measurements acquired by the two ultrasonic transducers, the LV volume was estimated well. However, the accuracies obtained are strongly dependent on the choice of the design parameters. Orientations toward the septum perform better, as they interfere less with the papillary muscles. The optimized design is valid for all hearts. Considering this, the Bland‐Altman analysis reports the LV volume accuracy as a bias of ±10% and limits of agreement of 0%–40% in all but the smallest heart. The simplicity of traditional echocardiography systems was reduced by two orders of magnitude in technical complexity, while achieving a comparable accuracy to 2D echocardiography requiring a calibration of absolute volume only. Hence, our approach exploits the established benefits of echocardiography and makes them applicable as an LV volume sensor for LVADs.  相似文献   
4.

Background  

The generation of an atraumatic posterior vitreous detachment (PVD), a common goal in vitreoretinal surgery, is a challenge particularly in children and young trauma patients. Plasmin has been proposed as a surgical adjunct to enzymatically generate a PVD. This study assesses the performance and safety of a new system for rapid purification of plasmin as an adjunct to vitrectomy.  相似文献   
5.
Transcranial duplex sonography in the detection of patent foramen ovale   总被引:4,自引:0,他引:4  
PURPOSE: To determine the sensitivity of contrast material-enhanced transcranial color-coded sonography (c-TCCS) compared with that of contrast-enhanced transesophageal echocardiography (c-TEE) for detection of cardiac right-to-left shunt. MATERIALS AND METHODS: Forty consecutive patients with stroke or transient ischemic attack were admitted to the hospital and were examined by using c-TCCS and c-TEE. High-intensity transient signals (HITS) were counted for 25 seconds after the end of the Valsalva maneuver, and the numbers of HITS were classified in one of four categories (zero HITS, one to 10 HITS, >10 HITS without curtain, and curtain). A statistically significant difference was calculated with the Fisher exact test. RESULTS: HITS were counted in 21 (52%) patients by using c-TCCS and c-TEE. With both tests, no HITS were counted in 15 (38%) patients. In two (5%) patients, no HITS were counted with c-TEE but three HITS in one patient and five HITS in the other were counted with c-TCCS. In two (5%) patients, no HITS were counted with c-TCCS, but a small patent foramen ovale (PFO) was seen at c-TEE. With c-TCCS, the sensitivity was 91% (21 of 23) and the specificity was 88% (15 of 17). In 23 patients examined with c-TCCS, 14 (61%) patients had category 1 PFO; seven (30%) patients, category 2 PFO; and two (9%) patients, category 3 PFO. Mean HITS count in patients with category 1 PFO was 4.4 and that for those with category 2 PFO was 27.6. CONCLUSION: c-TCCS is a sensitive noninvasive method for detecting cardiac right-to-left shunt and is as sensitive as c-TEE.  相似文献   
6.
7.
The aim of the present in vitro and in vivo studies was to compare the permeation and penetration of a 2.5% ketoprofen (CAS 22071-15-4) gel [Phardol Schmerz-Gel (Test-D)] with the permeation and penetration of two other ketoprofen gels (Ref-I, Ref-E) and an ibuprofen (CAS 15687-27-1) gel (Ref-D) on excised human skin. Furthermore, in vivo studies were performed. The permeation studies utilizing static Franz diffusion cells allow the determination of the transdermal (systemic) transport, whereas the penetration studies in vitro (according to the Saarbrücker model) and in vivo permit setting up a concentration-depth profile. For this purpose the permeation kinetics of ketoprofen from three different gels (each containing 2.5% ketoprofen) over a period of two days were determined at heat-separated human skin of different donors. The in vitro permeability coefficients for Test-D (6.50 x 10(-7) cm x s(-1)) and Ref-I (5.72 x 10(-7) cm x s(-1)) were comparable and the transport occurred for both by a factor of 8-9 faster than with Ref-E (0.78 x 10(-7) cm x s(-1)). In parallel to the permeation studies with ketoprofen, the permeability coefficient of caffeine from an ointment was assessed using the skin biopsies of the same donors as a quality assurance. In a second part of the studies, the in vitro penetration of ketoprofen from Test-D was determined over a period of 3 h at three different skin biopsies in comparison to a commercially available 5% ibuprofen gel (Ref-D). As a main result a concentration-depth profile for ketoprofen and ibuprofen could be issued. The ketoprofen (37.7 +/- 12.1 microg/cm2) and the ibuprofen (30.1 +/- 6.0 microg/cm2) penetrate to the same order of magnitude into the upper part of the Stratum corneum, whereas ibuprofen stronger accumulates in the deeper layers (ketoprofen: 27.3 +/- 8.5 microg/cm2; ibuprofen: 73.7 +/- 31.1 microg/cm2). An additional in vivo penetration study was performed with Test-D to set up an in vitro-in vivo (IVIV) correlation. Over a period of 3 h, the amount of ketoprofen in the Stratum corneum in vivo was 78.4 +/- 19.1 microg/cm2 being comparable to the in vitro data.  相似文献   
8.
The study deals with the immunological capacity and perfusion rate of splenic grafts in pigs after autologous transplantation into the omentum majus. 12 months after the operation, the weight and relative perfusion of the regenerated tissue was clearly reduced. Independent of this fact, the splenic grafts could balance out an IgM-deficiency, observed due to splenectomy, 4 months after the transplantation. Furthermore, the number of antibody forming cells in the grafts was only slightly decreased compared to the normal spleen. These results show that regenerated splenic tissue is able to carry out specific immunological functions. One of the limiting factors in preventing postsplenectomy sequelae (i.e., sepsis) seems to be the poor regeneration weight and low perfusion of the grafts.  相似文献   
9.
Emergency operations were performed on 20 patients for perforated sigma diverticulitis with diffuse (n = 15) or locally delimited (n = 5) peritonitis, between 1979 and June 1986. The average age of the patients was 65.7 years. Sigma resection with closure of the rectosigmoid and colostomy, that is Hartmann's operation, was performed on all of them. The postoperative lethality was as high as 45 per cent (nine patients), but this was not attributable to complications for which the surgical method had to be blamed. Only one patient died of anastomosis dehiscence, following additional resection of part of the small intestine. All the other deaths (n = 8) had been caused by internal organic complications. Hence, lethality is believed to be controllable only by close cooperation from the very beginning between surgeon and specialist in intensive therapy. Re-anastomosis (generally three months from primary operation) can be simplified by means of mechanical staplers, with the risk being reduced to nearly nil. These are benefits that support the recommendation of Hartmann's operation as an emergency approach to perforated sigma diverticulitis. It can be performed even by the less experienced surgeon on night duty.  相似文献   
10.
Highly malignant thyroid tumours are frequently diagnosed only at an advanced stage where radical resection is no longer feasible. By the wide application of fine needle aspiration biopsy as a diagnostic tool in nodular thyroid diseases occasionally early stages of these tumours can be diagnosed. Despite early detection in 23% of our patients with anaplastic carcinomas and sarcomas of the thyroid gland and subsequent radical resection an improvement in the long-term outcome was not achieved. In contrast, thyroidectomy and appropriate oncologial therapy may result in long-term survival of patients with early stages of thyroid lymphomas.  相似文献   
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