A bifunctional CoP/N-doped porous carbon composite derived from a single source precursor for bisphenol A removal

Transition metal phosphides are promising materials for catalysis and their synthesis procedures commonly require costly or hazardous reagents. Herein, we adopted a yeast-extracted nucleic acid as an environmentally benign non-metal source to develop bifunctional cobalt phosphide/nitrogen-doped porous carbon composites. The single source precursor, i.e., a Co²⁺–nucleic acid complex was formed by coordination and could be converted to cobalt phosphide/carbon by pyrolysis with the assistance of a molten salt. Material characterization confirmed the formation of a well-crystallized CoP phase, N-doped carbon and hierarchical porous structure. In situ generated reducing gases (CO, H₂, PH₃, etc.) from the nucleic acid were detected by thermogravimetry-mass spectrometry (TG-MS) and thermogravimetry-infrared spectroscopy (TG-IR); also, they were suggested to be responsible for the transformation of phosphate in the precursor to phosphide in CoP. When applied for model pollutant (bisphenol A, BPA) removal, the developed composite not only exhibited considerable adsorption capability, but also performed well for peroxymonosulfate activation in an advanced oxidation process (AOP). In a two-step removal procedure, 75.5% of BPA was adsorbed in 60 min and the residual 24.5% of BPA could be degraded in 2 min by AOP. Further investigations verified that sulfate radicals, hydroxyl radicals and singlet oxygen were all involved in AOP for catalytic BPA degradation. The exhausted sample could also be regenerated by a facile thermal treatment approach. In this study, we have provided a facile strategy of utilizing inherent biomass components to construct an advanced metal phosphide-containing composite, which may open a new route for the value-added conversion of biomass.

Cost-effective and environmentally benign biomass precursor enabled synthesis of CoP/N-doped porous carbon nanocomposite for BPA removal through adsorption and peroxymonosulfate activation.     

Preparation of environmentally friendly acrylic pressure-sensitive adhesives by bulk photopolymerization and their performance

Polyacrylic pressure-sensitive adhesives (PSAs) based on butyl acrylate (BA), 2-hydroxyethyl acrylate (HEA), and acrylic acid (AA) were prepared by a bulk polymerization process triggered by a radical photoinitiator under UV irradiation and UV-crosslinking. 1,6-Hexanediol diacrylate (HDDA) with difunctional groups was introduced into the PSAs to modify semi-interpenetrating network structures. The effect of HDDA content on the pressure-sensitive performance was comprehensively tested. The viscosity of the prepolymer was measured by a rotational viscometer. Prepolymers obtained by a photoinduced process and UV crosslinking process were confirmed via Fourier transform infrared spectroscopy (FTIR). All double bonds participated in the copolymerization without any remaining monomers, which reflected the concept of green environmental protection. Gel content in the crosslinked portion was examined by Soxhlet extraction, whilst the soluble molecular weight of PSAs was characterized by gel permeation chromatography (GPC). The viscoelastic properties of polymer films were determined by dynamic mechanical analysis (DMA). The T_g value and storage modulus (G′) of the PSAs were enhanced with the addition of HDDA. Moreover, three fundamental adhesive properties, i.e. loop tack force, peel force and shear strength of PSAs, were measured. The results showed that UV crosslinking technology achieved a good balance of the three forces with excellent pressure-sensitive properties.

Polyacrylic pressure-sensitive adhesives based on butyl acrylate, 2-hydroxyethyl acrylate, and acrylic acid were prepared by a bulk polymerization process triggered by a radical photoinitiator under UV irradiation and UV-crosslinking.     

Potentiometric and UV-Vis spectrophotometric titrations for evaluation of the antioxidant capacity of chicoric acid

The antioxidant capacity (AOC) of chicoric acid (ChA, the main antioxidant component of Echinacea) or an ethanol/water-extract of Echinacea flowers was determined by potentiometric and UV-Vis absorption spectrophotometric titrations with ABTS˙⁺ radical cations as the oxidizing probe. The potentiometric and spectrophotometric titration results agreed well with each other. The trolox-equivalent antioxidant capacity (TEAC) of ChA was found to be 5.00 ± 0.07 (potentiometry) and 4.81 ± 0.06 (spectrophotometry) at pH 7.4, and the TEAC value has been proven to be actually equal to the ratio of the stoichiometric ratio of the ABTS˙⁺–ChA redox reaction to that of the ABTS˙⁺–trolox redox reaction. The TEAC of the ethanol/water-extract of Echinacea flowers, expressed in mM (trolox) per gram per liter (Echinacea extract), was found to be 0.241 ± 0.006 mmol g⁻¹ (potentiometry) and 0.240 ± 0.007 mmol g⁻¹ (spectrophotometry) at pH 7.4. The stoichiometric ratio of the ABTS˙⁺–ChA redox reaction varied from 10.8 to 3.2, depending on the solution pH and the final ABTS˙⁺–ChA concentration ratio. However, the stoichiometric ratio of the ABTS˙⁺–trolox redox reaction remained ca. 2.0 at various solution-pH values and final ABTS˙⁺–trolox concentration ratios. The unusual stoichiometric ratio of the ABTS˙⁺–ChA redox reaction is examined by potentiometric/spectrophotometric titrations and cyclic voltammetry, clearly revealing the new mechanism of a rapid redox process followed by a slow redox process at pH 7.4 and 9.0 when the ABTS˙⁺–ChA molar concentration ratio is greater than 4. The electrochemistry methods coupled with spectrophotometry can conveniently and reliably provide important quantitative and qualitative information on redox chemistry, and are expected to find wider applications in accurately evaluating the redox activities of many other natural/synthesized antioxidants and oxidants.

Potentiometric/spectrophotometric titrations have revealed the antioxidation behavior and mechanisms of chicoric acid (ChA, versus trolox) against ABTS˙⁺ radical cations.     

球后注射脐带间充质干细胞治疗糖尿病视网膜病变的护理

目的探讨球后注射脐带间充质干细胞治疗糖尿病视网膜病变的护理方法。方法对9例(17眼)糖尿病视网膜病变患者行脐带间充质干细胞球后注射治疗并实施系统护理。结果2眼视力提高0.5,出血灶、渗出基本完全吸收;8眼视力提高0.3,出血灶、渗出有所吸收,微血管瘤数减少;5眼视力提高0.2,出血灶、渗出略有吸收,无新鲜出血;2眼视力和眼底无变化。结论对糖尿病视网膜病变行球后注射脐带间充质干细胞治疗的患者术前进行心理疏导和血糖血压的调节,术中严密执行无菌操作常规,术后预防并发症可保证疗效。     

概念图护理查房对护士评判性思维能力的影响

目的探讨在护理查房中运用概念图对培养护士评判性思维能力的效果。方法将40名儿科护士按病区分为传统查房组(20名),采用传统模式进行护理查房;概念图查房组(20名)运用概念图进行护理查房。两组均每个月查房1次,持续12个月。采用评判性思维测评量表(CTDI-CV)测量干预前后两组评判性思维能力。结果实施前两组评判性思维总分及各特质得分比较,差异无统计学意义(均P>0.05);实施后两组评判性思维能力有不同程度的提高,但概念图查房组除寻找真相和认知成熟度外,其他特质和总分较传统查房组显著提高(P<0.05,P<0.01)。结论在护理查房中运用概念图,可开放思想,增强临床护士的求知欲和分析能力及系统化能力,提高评判性思维能力。     

The free triple chimeric dorsalis pedis flaps for repair of multifinger soft tissue defects: A report of two cases

The reconstruction of complex hand injury such as multifinger soft tissue defect remains a challenging problem. Two cases of repair of multifinger injury with exposed bones using the free chimeric flaps based on the dorsalis pedis vessels are presented. Two male patients, 46 years old and 36 years old, suffered from a thermocompression injury to the dorsum of fingers resulting in soft tissue defects of multiple fingers. The chimeric free flap was designed and applied to cover the defects. The donor sites were covered by skin grafts. The postoperative courses were uneventful. Both patients were followed up for 10–12 months. The maximal flexion angle of the distal interphalangeal, proximal interphalangeal, and metacarpophalangeal joints were 40°–85° at the end of the follow‐up. The protective sensation was achieved on the dorsal fingers. The report suggests that the free chimeric flaps based on the dorsalis pedis artery may be an alternative for the reconstruction of the multifinger dorsal soft tissue defects. © 2013 Wiley Periodicals, Inc. Microsurgery 33:660–666, 2013.     

Modified posterior soft tissue repair for the prevention of early postoperative dislocation in total hip arthroplasty

Purpose

Dislocation following total hip arthroplasty (THA) with the posterior approach has been quite a common and bothering complication. Previous researches suggest that careful repair of the posterior structures significantly reduces this risk. The purposes of the present study were to describe a modified posterior soft tissue repair procedure in THA using a suture anchor (TwinFix Ti 5.0, Smith & Nephew, Andover, MA) and evaluate the early postoperative dislocation rate.

Methods

From July 2004 to June 2008, 220 consecutive primary total hip arthroplasties were performed using the modified surgical approach. The average age in the group was 46.4 years (range from 21 to 90) at the time of the procedure. The rate of postoperative hip dislocation, as well as any signs of complications related to the technique, has been observed and analyzed in this study.

Results

There was no postoperative dislocation following primary THA in 220 cases, and no signs of complications related to the technique, such as greater trochanteric fractures and sciatic nerve palsy, have been noted in any of the cases at their most recent follow-up.

Conclusions

These initial results demonstrate that the modified repair in THA using the suture anchor can serve as an effective and reliable mean for prevention of early postoperative dislocation     

PTH‐enhanced structural allograft healing is associated with decreased angiopoietin‐2–mediated arteriogenesis,mast cell accumulation,and fibrosis

Recombinant parathyroid hormone (rPTH) therapy has been evaluated for skeletal repair in animal studies and clinical trials based on its known anabolic effects, but its effects on angiogenesis and fibrosis remain poorly understood. We examined the effects of rPTH therapy on blood vessel formation and osseous integration in a murine femoral allograft model, which caused a significant increase in small vessel numbers, and decreased large vessel formation (p < 0.05). Histology showed that rPTH also reduced fibrosis around the allografts to similar levels observed in live autografts, and decreased mast cells at the graft‐host junction. Similar effects on vasculogenesis and fibrosis were observed in femoral allografts from Col1caPTHR transgenic mice. Gene expression profiling revealed rPTH‐induced angiopoietin‐1 (8‐fold), while decreasing angiopoietin‐2 (70‐fold) at day 7 of allograft healing. Finally, we show anti‐angiopoietin‐2 peptibody (L1‐10) treatment mimics rPTH effects on angiogenesis and fibrosis. Collectively, these findings show that intermittent rPTH treatment enhances structural allograft healing by two processes: (1) anabolic effects on new bone formation via small vessel angiogenesis, and (2) inhibition of angiopoietin‐2–mediated arteriogenesis. The latter effect may function as a vascular sieve to limit mast cell access to the site of tissue repair, which decreases fibrosis around and between the fractured ends of bone. Thus, rPTH therapy may be generalizable to all forms of tissue repair that suffer from limited biointegration and excessive fibrosis. © 2013 American Society for Bone and Mineral Research.