[Harmonic scalpel versus conventional resection in thyroid surgery: a meta analysis on the safety outcomes].

OBJECTIVE: To compare the safety between harmonic scalpel and conventional resection in total or near total thyroidectomy with meta-analysis. METHODS: The prospective randomized controlled studies were searched for in electronic databases (MEDLINE, EMBASE, Cochrane Library). Meta analysis of acquired data was performed through the use of RevMan 5.2 software. RESULTS: According to the inclusion criterion, 13 articles were enrolled which compared on the safety between harmonic scalpel and conventional resection in thyroid surgery. A total of 1620 patients with thyroid tumor were enrolled, including 802 patients in harmonic scalpel group and 818 patients in conventional resection group. Compared with conventional resection group, the harmonic scalpel group showed shorter time of surgery, the weighted mean difference (WMD) and their 95% confidence interval (95%CI) was -21.06[-25.65, -16.47], Z = 8.99, P < 0.00001; less intra-operative blood loss, WMD and 95%CI was -14.36[-20.67, -8.06], Z = 4.46, P < 0.00001; less post-operative drain output (WMD and 95%CI was -7.47[-11.35, -3.58], Z = 3.77, P = 0.0002); less hospitalization charges (WMD and 95%CI was -117.97[-131.65, -104.29], Z = 16.90, P < 0.00001). The incidence of postoperative transient recurrent laryngeal nerve dysfunction and transient hypocalcemia were similar in both groups. CONCLUSION: Using the harmonic scalpel in thyroid surgery was as safe as that of the conventional technique with the advantage of shorter time of surgery, less intraoperative blood loss and less postoperative drain output.

[Use of uncut Roux-en-Y reconstruction after distal gastrectomy for gastric cancer].

OBJECTIVE: To evaluate the clinical efficacy of uncut Roux-en-Y reconstruction after distal gastrectomy for gastric cancer. METHODS: Clinical data of 419 patients who underwent distal gastrectomy for gastric cancer with complete follow-up data between March 2005 and March 2008 in the Cancer Institute and Hospital of Tianjin Medical University. Patients were divided into B I (138 cases with Billroth I reconstruction), M-B II (108 cases with modified Billroth II reconstruction), RY (46 cases with Roux-en-Y reconstruction) and Uncut RY (127 cases with uncut Roux-en-Y reconstruction) according to reconstructive methods. RESULTS: Patients in the Uncut RY group had a larger tumor diameter, more T3, and poorer stage of disease compared to those in the B I (P<0.05). In Uncut RY group, the operative time and postoperative hospital stay were(132.6±19.2) minutes and (10.4±1.2) days respectively, shorter than those in RY group (142.5±11.7) minutes and (12.1±3.7) days(both P<0.05), alkaline reflex gastritis rate was 3.2%, lower than that in B I group (24.6%, P<0.05) and M-B II group (25.9%, P<0.05). Marginal ulcer rate in uncut RY group was lower compared to M-B II group (P=0.019), and incidence of Roux-en-Y stasis syndrome was less compared to RY group (P=0.000). CONCLUSIONS: The uncut Roux-en-Y reconstruction is both feasible and safe. It can prevent alkaline reflex gastritis and Roux-en-Y stasis syndrome. It may be the preferred technique for reconstruction after distal gastrectomy.

[A retrospective analysis of clinicopathological characteristics and prognostic factors of gastric stump cancer].

OBJECTIVE: To explore the clinicopathological characteristics and prognostic factors of gastric stump cancer(GSC). METHODS: The clinical data of 138 patients with GSC treated from January 1992 to July 2008 were reviewed and analyzed. The patients included 122 males and 16 females with a mean age of 61.5 years, and the mean interval between the initial operation and second diagnosis was 21.9 years. RESULTS: The endoscopy and pathological examination showed Borrmann III/IV in 127 (92.7%) patients and undifferentiated carcinoma in 115 (83.3%) patients. The resectability and radical resectability rate were 72.4% and 59.4%. The 1-, 3- and 5-year survival rates was 59.2%, 30.1% and 14.2%, respectively. The median overall survival time was 19.4 months. Univariate Log-rank test indicated that Borrmann type, histological type, tumor diameter, TNM stage, depth of invasion, number of metastatic lymph node, distant metastasis and option of treatment were significant prognostic factors for GSC. While TNM stage, depth of invasion, distant metastasis and option of treatment were prognostic factors on multivariable analysis. The median survival time of patients underwent radical resection was significantly longer (36 months) than that of patients received palliative resection (8 months, P < 0.05) and chemotherapy only (5 months, P < 0.05). Among patients with a tumor of T4 stage, the median survival time was statistically prolonged by combined evisceration (18.6 months) when compared with the patients received palliative surgery. CONCLUSIONS: TNM stage, depth of invasion, distant metastasis and option of treatment are independent prognostic factors for GSC. Early diagnosis and radical resection may play an important role in improving the prognosis of GSC.

[Prognostic significance of preoperative serum albumin level in patients with gastric cancer].

OBJECTIVE: To evaluate the prognostic significance of preoperative serum albumin in patients with gastric cancer undergoing radical resection. METHODS: A total of 146 patients with gastric cancer underwent radical resection from January 2001 to December 2003. Clinicopathological data were analyzed retrospectively. Patients were divided into two groups, including patients with a normal preoperative serum albumin level(>35 g/L, n=115) and patients with hypoalbuminemia (≤35 g/L, n=31). RESULTS: Patients with a low albumin level were associated with a higher postoperative recurrence rate(90.3% vs. 43.5%, P<0.01). The overall 5-year survival rate in patients with a normal serum albumin level was significantly higher than that in patients with a low serum level(57.4% vs. 9.7%, P<0.01). On multivariate analysis, preoperative serum albumin level was an independent factor associated with survival(P<0.01). When stratified by nodal metastasis, normal serum albumin level was still associated with higher survival rate(P<0.05). Prognostic significance was found in patients with lower stomach cancer(P<0.01), but not in patients with cancer in the upper and middle stomach(P>0.05). CONCLUSION: Hypoalbuminemia is associated with worse survival in patients with cancer in the lower stomach and adjuvant therapy should be considered.

[Prognosis of patients with recurrence after curative resection of advanced gastric cancer].

OBJECTIVE: To investigate the clinical features and prognosis of recurrent gastric cancer. METHODS: Clinical data of 163 patients with recurrent gastric cancer from Jan. 2001 to Jan. 2005 were reviewed. Patients were compared between those with and without symptoms. RESULTS: Seventy-two patients(44.2%) were symptomatic, while 91(55.8%) were asymptomatic. There were significant differences in lymph node metastasis between the two groups(P<0.05). The median overall survival was significantly longer in asymptomatic patients (19.8 vs. 15.7 months, P<0.05). Post-recurrence survival was also longer in the asymptomatic group (9.5 vs. 4.8 months, P<0.01). The median recurrence-free interval in asymptomatic patients was 10.0 months, which was significantly longer than that in the symptomatic patients (9.2 months, P<0.05). On univariate survival analysis,post-gastrectomy chemotherapy (P<0.05), symptoms of recurrence(P<0.01), TNM staging(P<0.01), recurrence-free interval (P<0.01), and reoperation(P<0.01) were associated with the prognosis. On multivariable analysis, TNM staging(P<0.01), symptoms of recurrence(P<0.01), recurrence-free interval (P<0.05), and reoperation(P<0.05) were independent risk factors. CONCLUSIONS: Patients with recurrent gastric cancer have poor prognosis. Close monitoring and active follow-up of patients with gastric cancer should be conducted during the first two years after operation. Reoperation may improve survival in patients with recurrent gastric cancer.

[Analysis of treatment and prognosis in 132 patients with gastric gastrointestinal stromal tumors].

OBJECTIVE: To investigate the clinicopathological characteristics, diagnosis, treatment and prognostic factors of gastric gastrointestinal stromal tumors(GIST) in the stomach. METHODS: The clinicopathological data of 132 patients with gastric GIST between January 1998 and December 2008 were analyzed retrospectively, and the prognostic factors were evaluated. RESULTS: Tumor locations were the cardia or fundus (50, 37.9%), the stomach body (62, 47%),the antrum (13, 9.8%), and two regions were found in 6 cases (4.5%), three regions in 1 cases (0.8%). Tumor size ranged from 1.0 to 27.0 cm with an average of 9.4 cm. All the patients underwent complete tumor resection, including multi-organ resection in 41 cases. Thirty-four cases underwent lymph node dissection. All the lymph nodes were negative. The positive rate was 93.2% (23/132) for CD 117 and 82.6% (109/132) for CD34. The 1-,3- and 5-year survival rates of the 118 cases with follow up were 94.7%, 80.2%, and 56.6%, respectively. Univariate analysis revealed that the differences in Fletcher classification, tumor size, infiltration to surrounding tissue, preoperative metastasis, and adjuvant postoperative therapy with imatinib were related to the survival rates. Multivariate analysis demonstrated that Fletcher classification, preoperative metastasis and adjuvant postoperative therapy with imatinib were independent poor prognostic factors for survival. CONCLUSIONS: Preoperative metastasis is an independent factor predicting poor prognosis of gastric GIST. Fletcher classification can be used to evaluate the biological behaviors and prognosis, while surgery is the main therapy and targeted therapy can improve survival of gastric GIST.

[Prognostic analysis on primary duodenal adenocarcinoma].

OBJECTIVE: To investigate the prognostic factors of primary duodenal adenocarcinoma. METHODS: The medical records of 67 patients with primary duodenal adenocarcinoma treated in our hospital from January 1990 to December 2005 were retrospectively analyzed. Prognostic factors were analyzed by univariable and multivariable analysis. RESULTS: Of the 67 patients, 38 underwent curative resection and 29 underwent palliative resection. The overall 5-year survival rate was 22.4%. The survival was significantly higher in patients who underwent curative resection (5-year survival 39.5%) than that in those who underwent palliative resection(5-year survival 0) (P<0.05). Univariable analysis showed that T-stage, nodal metastasis and tumor stage had significant negative effects on the survival of patients who underwent curative resection. However, multivariable analysis revealed that T-stage and nodal metastasis were significantly associated with survival. CONCLUSIONS: Curative resection may improve the survival. T-stage and lymph nodes metastasis are associated with decreased survival.

[Clinicopathological features and prognosis of 68 patients with metastatic ovarian tumors from the gastric cancer].

OBJECTIVE: To investigate the clinicopathological features and prognosis of metastatic ovarian tumors from gastric cancer. METHODS: Clinical data of 68 patients with metastatic ovarian carcinoma were reviewed retrospectively. RESULTS: The median age was 46 years. The majority of these patients was in the premenopausal state (67.6%) and had bilateral ovarian involvement (64.7%). Pathological type was signet-ring cell carcinoma in 52.9% of the cases. Most of them underwent surgical treatment or chemotherapy or both. The median overall survival was 14.1 months, and the median progression-free survival was 6.7 months. The survival rates in 1-, 3- and 5-year were 54.8%, 14.9% and 0, respectively. Univariable analysis revealed that resection of gastric cancer, lymphatic metastasis, pathologic type of metastatic ovarian tumor, extent of metastatic lesion, cytoreductive surgery and chemotherapy for metastatic ovarian carcinoma were associated with the prognosis. Multivariable analysis revealed that cytoreductive surgery and extent of metastatic lesion were independent factors. Patients with metastatic lesion confined to the ovaries had a median overall survival of 16.0 months as compared to 8.6 months for those with more extensive metastases (P<0.01), and had a median progression-free survival of 8.2 months as compared to 4.1 months for those with more extensive metastases (P<0.05). Patients who underwent optimal cytoreduction(residual lesion < or =2 cm) had a median overall survival of 16.0 months as compared to 9.7 months for those who received suboptimal cytoreduction (residual lesion >2 cm) ( P<0.01). Optimal cytoreduction was also associated with a significantly longer median progression-free survival (11.0 months) as compared to suboptimal cytoreduction median progression-free survival (3.1 months) (P<0.01). CONCLUSIONS: Prognosis of patients with metastatic ovarian carcinoma from gastric cancer is quite poor. Extent of metastatic lesion is an independent factor. Optimal cytoreduction is associated with improved survival.

[Theoretical thinking in sustainable city construction of China].

Based on the concept of ecosystem services and welfare, a definition of a sustainable city is proposed, and a quantitative model to describe sustainable welfare is established. With the analysis of the major issues and driving forces of sustainable city construction in China, the approaches for sustainable city construction are proposed as follows: to promote study on the theory and methodology of sustainable city construction, to set up and perfect institutional and management systems, and to establish a performance assessment system and an effective operation mechanism for sustainable city construction in China.

Characteristics of poloxamer thermosensitive in situ gel of dexamethasone sodium phosphate / 药学学报

Thermosensitive in situ gel is a novel drug delivery system which can form gel in situ after injection of the polymer solution into the body and releases the drug in a controlled manner, thus provides a promising strategy for localized drug delivery. The aim of the present work is to investigate the characteristics including gelation temperature, sol-gel transition temperature (T(s-g)), gel strength, stable viscosity, erosion and drug release behavior of the thermosensitive in situ gel which are composed of different concentrations of poloxamer Pluronic F127 and F68. The gelation temperature was determined by tube-reverse method. Rheological measurements were carried out to evaluate T(s-g), stable viscosity and gel strength. Erosion of the gels and release of dexamethasone sodium phosphate (DSP) from the gels were investigated by membrane-free method and HPLC. Increased F127 concentration in gel decreased the gelation temperature, T(s-g) as well as erosion of the gel and drug release rate, while viscosity and gel strength rose accordingly. However, increased F68 in gel could lead to the opposite result. The poloxamer solution below T(s-g) is Newtonian fluid with comparatively low viscosity, but shows the characteristics of the pseudoplastic fluid when temperature rises near to T(s-g). Drug release was controlled by the erosion of the gel matrix, and both of them followed the zero-order kinetics. An optimized formation containing 22.5% F127 and 2.5% F68 showed more desirable characteristics which meet the clinical requirements and is of potential in future clinical therapy.

Characterization of microstructure of ibuprofen-hydroxypropyl-beta-cyclodextrin and ibuprofen-beta-cyclodextrin by atomic force microscope / 药学学报

The microstructures of ibuprofen-hydroxypropyl-bets-cyclodextrin (IBU-HP-beta-CyD) and ibuprofen-beta-cyclodextrin (IBU-beta-CyD) were observed by atomic force microscope (AFM). The high resolving capability of AFM has the tungsten filament probe with the spring constant of 0.06 N x m(-1). Samples were observed in a small scale scanning area of 10.5 nm x 10.5 nm and 800 x 800 pixels. The original scanning images were gained by tapping mode at room temperature. Their three-dimensional reconstruction of microstructure was performed by G3DR software. The outer diameters of HP-beta-CyD and beta-CyD are 1.53 nm. The benzene diameter of IBU is 0.62 nm, fitting to the inner diameters of HP-beta-CyD and beta-CyD. The benzene and hydrophobic chain of IBU enter into the hole of cyclodextrin at 1:1 ratio. The results were evidenced by IR, X-ray diffraction and the phase solubility.

[Community composition and dynamics of airborne bacteria in Beijing].

Airborne bacteria are important biological components of the aerosol. They have a close relation with human health. The much higher concentrations can result in kinds of microbial disease. Using BIOLOG identification technology, the study on the community structure and dynamics of airborne bacteria was carried out in three typical functional areas in Beijing by systemic site sampling. Results show that the gram positive bacteria contributing 80%-85% were much more than the gram negative bacteria. Amongst 47 genera of bacteria including 31 Gram positive bacteria and 16 Gram negative bacteria, Micrococcus, Staphylococcus, Bacillus, Corynebacterium, and Pseudomonas were dominant, and Micrococcus contributing 20%-30% was the most dominant genus. The concentration of airborne bacteria was significant lower in GGR than in CER and MTL. In a year, the bacterial concentrations of summer and autumn were much more than those of winter and spring in CER and MTL, and there were no significant variations of bacterial concentrations in GGR. In different periods, the lower concentration of airborne bacteria was exhibited at 13:00.

[Equilibrium sorption isotherm for Cu2+ onto Hydrilla verticillata Royle and Myriophyllum spicatum].

Equilibrium sorption isotherms for Cu2+ onto Hydrilla verticillata Royle and Myriophyllum spicatum were studied. Both methods of linear and non-linear fitting were applied to describe the sorption isotherms, and their applicability were analyzed and compared. The results were: (1) The applicability of simulated equation can't be compared only by R2 and chi2 when equilibrium sorption model was used to quantify and contrast the performance of different biosorbents. Both methods of linear and non-linear fitting can be applied in different fitting equations to describe the equilibrium sorption isotherms respectively in order to obtain the actual and credible fitting results, and the fitting equation best accorded with experimental data can be selected; (2) In this experiment, the Langmuir model is more suitable to describe the sorption isotherm of Cu2+ biosorption by H. verticillata and M. spicatum, and there is greater difference between the experimental data and the calculated value of Freundlich model, especially for the linear form of Freundlich model; (3) The content of crude cellulose in dry matter is one of the main factor affecting the biosorption capacity of a submerged aquatic plant, and -OH and -CONH2 groups of polysaccharides on cell wall maybe are active center of biosorption; (4) According to the coefficients qm of the linear form of Langmuir model, the maximum sorption capacity of Cu2+ was found to be 21.55 mg/g and 10.80mg/g for H. verticillata and M. spicatum, respectively. The maximum specific surface area for H. verticillata for binding Cu2+ was 3.23m2/g, and it was 1.62m2/g for M. spicatum.

[Zoning planning in non-point source pollution control in Hanyang district].

It is most important for managing urban non-point source (NPS) pollution, actualizing the urban sustainable development as well, that zoning planning of urban NPS pollution control is studied. A case study on principles and methods of zoning planning in urban NPS pollution is carried out. Principles of urban sustainable development, priority of urban NPS pollution sensitivity, similarity of urban NPS control direction and region conjugate are put forward. Besides, it is for the first time that a more quantitive method is presented, in the case of Hanyang district, Wuhan city, which is based on L-THIA model and spatial analysis technique in GIS. Assessment of NPS pollution status quo, as well as analysis of NPS sensitivity, is the kernel component of the quantitive method. Hanyang might be divided into four NPS pollution control zones. It is helpful for decision-making of regional NPS pollution control.

[Current situation and impact factors of acid deposition in main cites of Shandong Province].

Based on the monitoring data for years in Shandong Province, current situation of acid rain in every city was assessed, and the temporal distribution of the dry, wet and total sulfur deposition in Jinan and Qingdao were studied. The results showed that Qingdao which had the largest precipitation acidity was the single city whose annul average precipitation pH was below 5. 60. The precipitation acidities in the main cities of Shandong Province were in a descent tendency. The total sulfur desposition in Jinan and Qingdao was basically stable or in a descent tendency, but also reached 10 t/(km(2)x a) or so. Among the total sulfur deposition flux, the dry deposition of sulfur had the greater contribution, and the contribution of SO2 dry deposition was higher than that of SO42- dry deposition. By analyzing the relation between the precipitation acidity and the SO2 discharge intensity, soil acidity and meteorological condition, the impact factors of acid precipitation in the cities of Shandong Province were revealed.

[Ecological protection and sustainable utilization of Erhai Lake, Yunnan].

Economic development and increase of population pressure have caused a series of ecological environmental problems of Erhai Lake. These problems include: (1) Quickening of eutrophication process, (2) Decrease of water level and water resources, (3) Habitat deterioration of lakeside zone, and (4) Overfishing and slow depletion of aboriginal fish. Pollutant loading of Erhai Lake is as follows: COD(Cr) 3 008 t x a(-1), TP 137.31 t x a(-1), TN 1 426.35 t x a(-1). According to the mestrophic target of water quality, loading of nitrogen and phosphorus is far above environmental capacity of Erhai Lake. Erhai Lake is now in a pivotal and hypersensitive period of trophic states change, and the position is very critical. Therefore, some countermeasures to solve the problems are presented as follows: (1) Defining the dominant functions of Erhai Lake, (2) Paying attention to the adjustment of the industrial structure and distribution in the course of urbanization, (3) Setting up lakeside zone reserve, (4) Strengthening the control of tourism pollution, (5) Properly adjusting the water level of Erhai Lake, and (6) Some ecological engineering measures for water resources protection in the basin should be taken through collecting and treating of urban sewages, ecological rehabilitating of the main inflowing rivers, constructing of ecological agricultures and improving of rural environment, ecological restoring of aquatic ecosystem, and soil and water conservation.

[Analysis of China's energy consumption and its impact on the environment in the future].

With the development of economy and urbanization, energy consumption and its impact on the environment in the future have become a focal point in China. Based on briefly reviewing energy consumption during 1980-2000 and analyzing its impact, three scenarios are assumed to forecast energy consumption status and analyze its impact on the environment in the future. The results indicate that the emissions of SO2, NOx, CO2 and soot dust caused by energy consumption would keep a high level in the future, and there are significant differences among the three scenarios' estimates. Improving energy efficiency and strengthening the exploitation and utilization of clean and renewable energy are suggested to mitigate the environmental pollution.

[Nitrogen bio-cycle in the alpine tundra ecosystem of Changbai Mountain and its comparison with arctic tundra].

The nitrogen bio-cycle was discussed in the alpine tundra ecosystem of Changbai Mountain through compartment model. The alpine tundra of Changbai Mountain was compared with Arctic tundra by the common ratio of genus and species in this paper. It was found that the 89.3% of genus and 58.6% of species was the common between Changbai alpine tundra and Arctic tundra while 95.5% of lichen genus and 58.7% lichen species, 82.1% of moss genus and 76.3% of moss species, 93.1% of vascular bundle genus and 40.5% of vascular bundle species were the common, respectively, which made vegetation type or community to be similar between Changbai alpine tundra and Arctic tundra. The total storage of nitrogen was 65220.6 t in the vegetation-plant system of Changbai Mountain, of which soil pool amounted to 99.3%. The nitrogen storage of each compartment was as follows: the vegetation pool, litterfall pool and soil pool were 237.4 t, 145.3 t and 64837.9 t respectively. The transferable amounts of nitrogen were 131.7 t x a(-1), 58 t/a and 73.7 t x a(-1) in the aboveground plant, belowground root system and litterfall of alpine tundra ecosystem of Changbai Mountain.

Impacts of sewage irrigation on heavy metal distribution and contamination in Beijing, China.

A potential hazard to Beijing was revealed due to the accumulation trend of heavy metals in agricultural soils with sewage irrigation, which results in metal contamination and human exposure risk. Samples including soils and plants were collected to assess the impacts of sewage irrigation on the irrigated farming area of Beijing. Concentrations of the five elements Cd, Cr, Cu, Zn, and Pb were determined in samples to calculate the accumulation factor and to establish a basis for environmental protection and the suitability of sewage irrigation for particular land use in the urban-rural interaction area of Beijing. Using reference values provided by the Beijing Background Research Cooperative Group in the 1970s, the pollution load index (PLI), enrichment factor (EF), and contamination factor (CF) of these metals were calculated. The pollution load indices (sewage irrigation land 3.49) of soils indicated that metal contamination occurred in these sites. The metal enrichment (EF of Cd 1.8, Cr 1.7, Cu 2.3, Zn 2.0, Pb 1.9) and the metal contamination (CF of Cd 2.6, Cr 1.5, Cu 2.0, Zn 1.7, Pb 1.6) showed that the accumulation trend of the five toxic metals increased during the sewage irrigation as compared with the lower reference values than other region in China and world average, and that pollution with Cd, Cu, Zn, and Pb was exacerbated in soils. The distributions of these metals were homogeneous in the irrigation area, but small-scale heterogeneous spatial distribution was observed. Irrigation sources were found to affect heavy metal distributions in soils. It was suggested that heavy metal transfer from soils to plants was a key pathway to human health exposure to metal contamination. However, with the expansion of urban areas in Beijing, soil inhalation and ingestion may become important pathways of human exposure to metal contamination.

Equilibrium and kinetics of copper(II) biosorption by Myriophyllum spicatum L.

The potential use of Myriophyllum spicatum L. biomass as a biosorbent for the removal of copper(II) from aqueous solution was investigated in laboratory condition. The sorption experiments were undertaken to obtain copper(II) biosorption properties of M. spicatum L., i.e. equilibrium time, the maximum capacity, and rate constants. Copper(II) biosorption was fast and equilibrium was attained within 35 min at initial copper(II) concentration of 6 mg/L. Different isotherm models including the Langmuir, Freundlich, Temkin and Redlich-Peterson model, were used to investigate the sorption capacity and isotherm. These models showed an excellent match with the experimental data except for the Freundlich model. According to the Langmuir coefficients, the maximum sorption capacity of copper onto M. spicatum L. was 10.80 mg/g. The kinetics of copper(II) sorption was also analysed and rate constants were derived. It was found that the overall sorption process was best described by the pseudo second-order equation, and that intraparticle diffusion was not the rate determining step. The results of this study showed that M. spicatum L. can be considered as useful vehicles for the removal and recovery of copper(II) from aqueous solutions.