Fe/sponge structure peanut shell carbon composite preparation for efficient Fenton oxidation crystal violet.

In order to obtain super synergy effect between adsorption and Fenton oxidation for crystal violet (CV) removement from water, in this study, Fe modified on a sponge structure peanut shell carbon (Fe/SPSC) nanocomposite was successfully synthesized by a wet impregnation method. In the Fe/SPSC sample, the prepared peanut shell carbon had a sponge-like structure, (002) crystal plane of graphite crystallite, and Fe/SPSC composite coexisted Fe2O3 and Fe3O4 crystalline, which could adsorb and enrich crystal violet molecule, decrease the concentration of CV solution rapidly. And also SPSC could do better for electrons transfer and further promote CV oxidation degradation. The removal efficiency results showed that the 7% Fe/SPSC (500 °C, 2 h) had the best CV removal activity. The composite prepared under the optimum conditions is 2.0 g/L, 0.1 mL 30% H2O2, pH = 7.0, 300 mg/L crystal violet water solution, and the CV degradation rate can reach 95.5%, and the CV degradation amount for Fe/SPSC was 143.25 mg/g. It was confirmed that hydroxyl radicals (•OH) is the active center of Fenton oxidation degradation reaction. XPS results showed that Fe, O, and C elements coexist in the 7% Fe/SPSC composite, and N element content increases after the reaction. Remarkable synergies between adsorption and Fenton oxidation, which could make Fe/SPSC, have quick CV abatement ability. The possible systematic effect mechanism of adsorption and Fenton-oxidation CV was also supplied. The present system has advantages on high CV dye degradation performance, no other Fe sludge formation, short reaction time, and better catalyst reusability.

High Efficiency Uranium(VI) Removal from Wastewater by Strong Alkaline Ion Exchange Fiber: Effect and Characteristic.

In this study, we analyzed the removal efficiency of uranium(U(VI)) in wastewater at relatively low concentrations using strong alkaline ion exchange fiber (SAIEF). Static tests showed that the strong alkali fibers can purify U(VI) containing wastewater in a concentration range of 20-100 mg L-1 with an optimal pH of 10.5 and contact time of 15-30 min. Adsorption and desorption cycling tests indicated that, adsorbed uranium is easily desorbed by 0.1 mol L-1 HCl, and the fiber still maintained the original adsorption efficiency after eight cycles. According to dynamic penetration test results, the SAIEF saturation adsorption capacity was 423.9 mg g-1, and the effluent concentration of uranium through two series columns was less than 0.05 mg L-1, reaching the national standard for non-receiving water (GB23727-2009) SEM-EDS and FTIR analysis revealed that the functional group of SAIEF is CH2N+(CH3)3Cl-. Addotionally, the major forms of fiber exchange adsorption are (UO2)2CO3(OH)3-, UO2(CO)34- and UO2(OH)3-. The results indicate that the SAIEF is an excellent material for uranium removal.

The Efficacy of Senna Bowel Preparation for Colonoscopy: A Systematic Review and Meta-analysis.

The quality of bowel preparation is an extremely important determinant of colonoscopy results. However, the efficacy of senna regimens in improving bowel cleanliness is uncertain. We conducted a systematic review and meta-analysis to synthesize data on whether using a senna bowel preparation regimen enhances the bowel cleanliness. We searched Web of Science Core Collection, MEDLINE, PubMed, Embase, Cochrane Library, and Scopus databases (from the inception to August 2021). The primary efficacy outcome was bowel cleanliness. Secondary outcomes included patient compliance, tolerance, and adverse events. Eleven trials fulfilled the inclusion criteria (3,343 patients. Overall, we found no significant differences in bowel cleanliness between the senna regimen and other bowel preparation regimens (odds ratio [95% confidence interval]: 1.02 [0.63, 1.67], p = 0.93). There was significant difference in tolerance (odds ratio [95% confidence interval]: 1.66 [1.08, 2.54], p = .02) and compliance (odds ratio [95% confidence interval]: 3.05 [1.42, 6.55], p = .004). The senna regimen yielded a significantly greater proportion of no nausea (odds ratio [95% confidence interval]: 1.84 [1.45, 2.32]) and vomiting (odds ratio [95% confidence interval]: 1.65 [0.81, 3.35]). Compared with other bowel preparation regimens, the senna regimen may be effective and safe in bowel cleaning before colonoscopy, with superior compliance and tolerance.

Consumption of processed food and risk of nasopharyngeal carcinoma: a systematic review and meta-analysis.

Background: Consumption of processed foods has been associated with nasopharyngeal carcinoma (NPC), but with inconsistent results. Therefore, we conducted a systematic review and meta-analysis to compute results regarding the association between processed foods and risk of NPC in included studies. Methods: Studies exploring the association between consumption of processed food and risk of NPC were included in the present study. All included studies were case-control or cohort designed. PubMed, Web of Science, EMBASE, Medline and Google Scholar databases were searched for articles published before July 2021. We recorded the following data: author, publication year, sample size, study type, study location, years of diagnosis, food item and comparison, and the covariates considered were multivariate adjusted odds ratios (ORs) or relative risks (RRs) with corresponding 95% confidence intervals (CIs) for the highest vs. lowest categories of processed food intake. STATA 12.0 software was used to compute the multivariate ORs or RRs and 95% CIs of the association. Quality appraisal was made using the Cochrane Risk of Bias Tool. Results: A meta-analysis was made for 29 case-control studies (including 14,378 NPC patients and 17,928 controls). The meta-analysis showed that the highest categories of processed food intake were associated with a 65% increase in NPC risk compared with the lowest categories in a random effects model (OR =1.67; 95% CI: 1.56-1.79; P value for Q test <0.001; I2=86.9%). Subgroup study showed significant positive associations regarding consumption of processed food and risk of NPC in both Asians and Caucasians (Asian: OR =1.68, 95% CI: 1.56-1.81; Caucasian: OR =1.36, 95% CI: 1.09-1.71). Conclusions: The association of processed foods with NPC risk might be significant. Further prospective studies and experimental research are needed to explore this relationship.

Symptom trajectories and influencing factors of prostate cancer following radical prostatectomy in Chinese patients.

BACKGROUND: Patients following radical prostatectomy will encounter various symptoms that may vary depending on the recovery of surgery and the use of adjuvant treatments. However, few studies have used the scale developed for prostate cancer to longitudinally assess the course of symptoms in Chinese patients. This study aimed to identify the symptom trajectories and the influencing factors in the prostate cancer patients of our area. METHODS: A prospective observational study was conducted, and 155 patients with prostate cancer from 3 hospitals in Shanghai were recruited. Demographic and disease-related information was collected during the hospitalization. Further information on symptoms, adjuvant treatment, and functional exercise was collected across 4 time points. Growth mixture modeling was used to identify the trajectory patterns of symptoms, and logistic regression was used to determine the predictors. RESULTS: A total of 143 patients completed the investigation of all points, with a lost-to-follow-up rate of 7.7%. Urinary incontinence, urinary tract irritation, sexual dysfunction, pelvic pain, and hormone related symptoms all had group heterogeneity, and the number of latent category trajectories obtained was 4, 3, 3, 4, and 3 respectively. There were differences in demographic, disease, and treatment-related information between the groups. CONCLUSIONS: Patients with prostate cancer have different symptom levels across different periods after radical prostatectomy. Medical staff can predict these changes based on the initial level of symptoms and related factors such as age, prostate volume, medical comorbidities, drug of adjuvant treatment to clarify the critical points, populations, and symptoms that require monitoring during follow-up.

Surgical strategies for glottic carcinoma with a giant thyroid tumor A case report and literature review.

Description of strategies for preventing surgical complications in the treatment of laryngeal carcinomas associated with giant thyroid cancer. For this study, the clinical data of an elderly patient with laryngeal carcinoma associated with a large thyroid tumor, diabetes and hypertension were used. The patient's tumor was removed with simultaneous surgery performed by the thyroid surgery department and the laryngeal surgery department; the patient was followed for more than 3 years and the scars of tracheal granulation and laryngeal adhesions were removed with repeated laser interventions. The literature review was carried out on the Wanfang database, on the China How Net database and on the MEDLINE database via Computer. The final research keywords used for the study were "squamous cell carcinoma" and "glottis" or "larynx" / "larynx", "surgery", "thyroid cancer" and "simultaneous surgery". RESULTS: After completion of the intervention, the nasogastric tube and tracheal cannula were successfully removed, the glottis was successfully reconstituted and oral respiration, phonation and oral feeding were normally resumed. CONCLUSION: The multidisciplinary approach for the simultaneous removal of a laryngeal carcinoma associated with a bulky thyroid tumor in elderly subjects with multi-system and multi-organ damage has been successfully implemented. There are only a few such cases presented in the literature to illustrate risk prevention strategies for postoperative complications, including postoperative infection, extubation difficulties and loss of speech, which deserve to be known. KEY WORDS: Glottic carcinoma, Thyroid tumor, Laser surgery multidisciplinary, Tracheal cannula, Vocal cords.

Ginsenosides induce extensive changes in gene expression and inhibit oxidative stress-induced apoptosis in human lens epithelial cells.

BACKGROUND: The effect of ginsenosides on the growth and apoptosis of human lens epithelial (HLE) B3 cells exposed to H2O2 was investigated. In addition, the effect of ginsenosides on gene expression in HLE-B3 cells was analyzed using microarray assays to determine its molecular mechanism. METHODS: HLE-B3 cells were treated with 1.75 M H2O2 in the presence or absence of 5, 10 or 20 µM ginsenosides. Cell viability and apoptosis were examined by MTT assays and flow cytometry, respectively, at 24 to 120 h after the treatment. Furthermore, HLE-B3 cells were treated with 20 µM ginsenosides for 8 days and total RNA was isolated and analyzed using the Affymetrix GeneChip Array. Principal component analysis was performed to visualize the microarray data. RESULTS: Addition of ginsenosides significantly alleviated the growth inhibitory effect of H2O2 on HLE-B3 cells and the percentage of viable cells was increased by more than 3 folds. Flow cytometric analysis showed that 6.16 ± 0.29% of H2O2-treated HLE-B3 cells were early apoptotic cells, and the percentage was reduced to 4.78 ± 0.16% (P < 0.05) in the presence of 20 µM ginsenosides. Principal component analysis revealed that ginsenoside caused extensive changes in gene expression in HLE-B3 cells. A total of 6219 genes showed significant differential expression in HLE-B3 cells treated with ginsenoside; among them, 2552 (41.0%) genes were significantly upregulated, whereas 3667 (59.0%) genes were significantly downregulated. FOXN2, APP and RAD23B were the top three upregulated genes while WSB1, PSME4 and DCAF7 were the top three downregulated genes in HLE-B3 cells treated with ginsenosides. CONCLUSION: Ginsenosides induce extensive changes in the expression of genes involved in multiple signaling pathways, including apoptotic signaling pathway and DNA damage response signaling pathway. Ginsenosides alleviate H2O2-induced suppression of the growth of HLB cells and inhibit H2O2-induced apoptosis of HLB cells.

Metalized Alkanedithiol Self-Assembled Monolayers (SAM) on Au Surfaces by an In Situ Autocatalytic Mechanism.

Here, a simple and general approach was developed for depositing metal nanoparticles on alkanedithiol self-assembled monolayers (SAMs) based on the spontaneous reduction of metal ions by the free SH sites of SAMs. By immersing the alkanedithiol SAM/Au in a corresponding metalcontaining solution (HAuCl4, AgNO3, H2PtCl6 and PdSO4), Au, Ag, Pt and Pd clusters, respectively, could be formed on top of the SAM/Au(111) electrode surface, which was confirmed by STM characterization. The size, morphology and coverage of clusters/islands can be tuned by modulating the immersion time, which allows for possible utilization of the metal/SAM/Au(111) in catalysis, nanoelectronics and biodetection.

Optimized terbium doped Ti/PbO2 dimensional stable anode as a strong tool for electrocatalytic degradation of imidacloprid waste water.

The presence of pesticides in water has emerged as a momentous environmental issue over the past decades. Herein, a terbium doped Ti/PbO2 (denoted as Ti/PbO2-Tb) dimensionally stable Ti/PbO2-Tb anode has been successfully prepared by one-step electrodeposition path for electrocatalytic degradation of imidacloprid (IMD) wastewater with high efficiency. Ti/PbO2-Tb electrode presents higher oxygen evolution potential, lower charge transfer resistance, stronger stability, longer service lifetime and outstanding electrocatalytic activity than Ti/PbO2 electrode. The optimum condition for IMD oxidation is obtained by analyzing the effects of some critical operating parameters including temperature, initial pH, current density and electrolyte concentration. It is proved that 70.05% of chemical oxygen demand and 76.07% of IMD are removed after 2.5 h of degradation under current density of 8 mA cm-2, pH 9, temperature 30 °C and 7.0 g L-1 NaCl electrolyte. In addition, the electrode displays commendable energy saving property as well as favorable reusability. The degradation mechanism of IMD is proposed by analyzing the intermediates identified by LC-MS. The present research provides a feasible strategy to degrade IMD wastewater by Ti/PbO2-Tb electrode.

Dimensionally stable Ti/SnO2-RuO2 composite electrode based highly efficient electrocatalytic degradation of industrial gallic acid effluent.

In this work, dimensionally stable Ti/SnO2-RuO2 electrode is successfully prepared using thermal decomposition method for the electrocatalytic degradation of high-concentration industrial gallic acid (GA) effluent in detail. The surface morphology, crystal structure and element analysis of as-prepared Ti/SnO2-RuO2 electrode are characterized by scanning electron microscopy, X-ray diffraction and X-ray fluorescence spectrometer, respectively. In addition, cyclic voltammetry, polarization curve and accelerated life tests are exploited to investigate the electrocatalytic activity and stability of Ti/SnO2-RuO2 electrode. Orthogonal experiment shows that, among the factors (current density, temperature and initial pH), current density is pivotal parameter influencing the degradation efficiency of industrial GA effluent. COD removal and degradation efficiencies of GA effluent reach up to 76.9% and 80.1% after 6 h, respectively, at the optimal conditions (current density of 10 mA cm-2, pH 6 and 35 °C). The degradation of GA effluent follows pseudo-first-order reaction kinetics. This work provides an in-depth theoretical support and application of electrocatalytic technology to the treatment of high-concentration industrial GA effluent.

Ti/PbO2-Sm2O3 composite based electrode for highly efficient electrocatalytic degradation of alizarin yellow R.

In this work, a novel Ti/PbO2-Sm2O3 composite electrode with high electrocatalytic activity is successfully fabricated via simple electrodeposition method and further investigated for electrochemical degradation of alizarin yellow R (AYR) wastewater. The test results of X-ray diffraction, field-emission scanning electron microscopy and energy-dispersive X-ray spectroscopy confirm that Sm2O3 is successfully composited with PbO2. The coating of Ti/PbO2-Sm2O3 composite electrode stacked by typical pyramid-like micro-particles exhibits smooth and compact surface morphology which is conducive to enhancing the corrosion resistance of electrode. Furthermore, electrochemical performance tests indicate that Ti/PbO2-Sm2O3 composite electrode has advantages of higher oxygen evolution potential, lower charge transfer resistance and longer lifetime over Ti/PbO2 electrode. Electrolyte concentration, plate space, initial pH and cell voltage are assessed to optimize the degradation condition of AYR. The results show that COD removal efficiency and degradation efficiency of AYR on Ti/PbO2-Sm2O3 composite electrode reach up to 79.90% and 80.00% under the optimal conditions (Na2SO4 electrolyte concentration 9.0 g L-1, plate space 3.0 cm, initial pH 5, cell voltage 3.0 V and electrolysis time 150 min), respectively. The degradation of AYR follows pseudo-first-order reaction kinetics, and a plausible mineralization pathway of AYR is proposed on the basis of the identification of major intermediate products. These results suggest that Ti/PbO2-Sm2O3 composite electrode is a promising candidate for electrocatalytic degradation of AYR wastewater.

Tunable odd-frequency triplet pairing states and skyrmion modes in chiral p-wave superconductor.

Bogliubov-de Gennes equations are solved self-consistently to investigate the properties of bound states in chiral p-wave superconductive disks. It shows that either an s-wave or the mixed d- and s-wave state with odd-frequency and spin-triplet symmetry is induced at the vortex core, depending both on the chirality of the pairing states and on the vortex topology. It is also found that the odd-frequency triplet even parity (OTE) bound state can be manipulated with a local non-magnetic potential. Interestingly, with an appropriate potential amplitude, the zero-energy OTE bound state can be stabilized at a distance from the vortex core and from the local potential. Possible existences of the Majorana fermion modes are expected if the particle-hole symmetry property is applied to the zero-energy OTE bound state. Moreover, skyrmion modes with an integer topological charge have been found to exist.

Cytochrome b5 reductase 2 is a novel candidate tumor suppressor gene frequently inactivated by promoter hypermethylation in human nasopharyngeal carcinoma.

Cytochrome b5 reductase 2 (CYB5R2), a member of the flavoprotein pyridine nucleotide cytochrome reductase family, is associated with a number of physiological reactions. However, its role in cancer, especially nasopharyngeal carcinoma (NPC), has not been addressed. Here, we investigate the transcript levels and promoter methylation status of CYB5R2 in NPC derived cell lines and tumor biopsies and experimentally address its role as a tumor suppressor gene. We find that CYB5R2 transcript levels are decreased in NPC cell lines and tumor biopsies. Promoter hypermethylation of CYB5R2 was detected in all six tested NPC cell lines and in 84% of primary NPC tumor biopsies but not in normal nasopharyngeal epithelium. Clinically, CYB5R2 methylation was associated with lymph node metastasis in NPC patients (P < 0.05). The endogenous expression of CYB5R2 could be restored in vitro by the methyltransferase inhibitor 5-aza-2'-deoxycytidine in NPC cell lines. Ectopic expression of CYB5R2 had an inhibitory effect on proliferation, clonogenicity and migration of NPC cells. Moreover, in vivo tests in nude mice indicated that ectopic expression of CYB5R2 reduces the tumorigenicity of CYB5R2-negative NPC cells. Collectively, these findings suggest that CYB5R2 may be a functional tumor suppressor gene, frequently inactivated by hypermethylation of its promoter in NPC. We report here the first instance of epigenetic downregulation in NPC tumor biopsies of a key enzyme, CYB5R2, which is responsible for the detoxification of environmental carcinogens. We propose the possibility of utilizing CYB5R2 promoter methylation as a diagnostic biomarker of NPC in the future.

Individual and combined toxic effects of cypermethrin and chlorpyrifos on earthworm.

Toxicities were assessed for a pyrethroid (cypermethrin) and an organophosphate insecticide (chlorpyrifos) individually and in combination. A series of tests were conducted on different responses (acute, chronic, behavioral) of earthworms of species Eisenia fetida andrei in the ecological risk assessment of these pesticides. The results showed that the toxicity of the mixture of cypermethrin and chlorpyrifos was significantly higher than either of these pesticides individually, especially on the earthworm's chronic responses. At a concentration of 5 mg/kg, the mixture caused significant reductions on the growth and reproduction rates of earthworms, but did not cause any significant effect when the individual was tested. The increase in toxicity of the pesticide mixture means that the use of toxicity data obtained exclusively from single-pesticide experiments may underestimate the ecological risk of pesticides that actually present in the field.

Longan flower extract inhibits the growth of colorectal carcinoma.

Longan flower extract (LFE) has been shown to exhibit free radical scavenging ability and anti-inflammatory effects. However, the effect of LFE treatment on the growth of colorectal cancer cells has not been evaluated. This study investigated the effect of LFE on two colorectal cancer cell lines, SW-480 and Colo 320DM, and the possible mechanisms involved. LFE-treated cells were assessed for viability by trypan blue exclusion, for in vitro tumorigenesis by seeding cells in soft agar to allow anchorage independent growth, for cell cycle distribution by flow cytometry, for loss of mitochondrial membrane potential by rhodamine 123 staining, for increased apoptosis by DNA fragmentation assay, and for changes in the levels of proteins involved in cell cycle control and apoptosis by immunoblotting. LFE (25-400 microg/ml) could inhibit proliferation in a dose- and time-dependent manner. The cell cycle of both LFE-treated cell lines showed obvious S phase block. Western blotting further showed the S phase block in these two cell lines was mainly due to cyclin E accumulation and cyclin A decrease. LFE treatment increased rhodamine 123-negative cells and DNA fragmentation in Colo 320DM cells but not in SW480 cells. Increased levels of the apoptosis activation protein, caspase 3, were also found in Colo 320DM cells. The activation of caspase 3 in LFE-treated SW480 cells was not significant. The caspase 3 activation in Colo 320DM cells by LFE was mediated by the suppression of Bcl-2 protein levels. LFE treatment could inhibit the proliferation and malignancy of colorectal cancer cell lines and was associated with S phase block of the cell cycle. An apoptotic mechanism induced by LFE involving a loss of mitochondrial membrane potential and caspase 3 activation was found in Colo 320DM cells but not in SW480 cells. The results of this study indicate that LFE has potential to be developed as a novel functional food or chemopreventive agent for colorectal cancer.

[Study on ultrasonic nebulizer sample feeding system for ICP-AES].

The sample feeding system of inductively coupled plasma atomic emission spectrometry (ICP-AES) is pneumatic nebulization system, but its efficiency is not good. The ultrasonic nebulization technology possesses advantages of high nebulization efficient and fine droplets, and it is free of blocking phenomenon. It has good application perspective in nebulization technology. In the present paper the authors study the working conditions of ultrasonic nebulizer such as carrier gas flow, injection time, injection rate and mode of washing that are likely to affect the detection results, and study the detecting conditions of several elements such as As and Se etc. that have poorly detection limits in normal ICP-AES methods. At the same time, the application of them in biochemical samples was studied. Testing results show that carrier gas flow, injection rate and injection time can greatly affect the intensity of spectral lines, and the ultrasonic nebulizer sample feeding system can increase the spectral line intensity and decrease the detection limit elements such as As, Pb, Se, Bi, Ge, Mo, Cd and Cu by about 10-25 times. Moreover, this ultrasonic nebulizer sample feeding system can reduce the time of memory effect by washing the sample cell.

Mechanisms of grape seed procyanidin-induced apoptosis in colorectal carcinoma cells.

BACKGROUND: Grape seed procyanidins (GSP) can inhibit cell proliferation and tumorigenesis, and induce apoptosis in human breast, prostate, skin and colorectal carcinoma cell lines. MATERIALS AND METHODS: In order to study the mechanism of apoptosis, four colorectal cell lines, HT-29, SW-480, LoVo and Colo 320DM, were used. GSP-treated cells were assessed for viability by trypan blue exclusion, for loss of mitochondrial membrane potential by rhodamine 123 staining, for increased apoptosis by annexin V labeling, and for changes in the levels of proteins involved in apoptosis by immunoblotting. RESULTS: GSP had no significant pro-apoptotic effect on the Colo 320DM cell line. In HT-29, SW-480 and LoVo cells, GSP (12.5-50 mg/l) inhibited proliferation in a dose-dependent manner. In these three lines, GSP treatment increased the proportion of rhodamine 123-negative cells and annexin V-positive cells, while immunoblotting revealed increased levels of apoptosis activation protein, caspase-3 and the cleavage fragment of PARP (a caspase-3 substrate), but the level of Bcl-2 did not change. CONCLUSION: GSP inhibited the proliferation of some colorectal carcinoma cell lines and was associated with an apoptotic mechanism involving a loss of mitochondrial membrane potential and caspase-3 activation in these cells.

Assessing cypermethrin-contaminated soil with three different earthworm test methods.

A series of tests (lethal, sublethal, and behavioral) on earthworms were conducted as an eco-assessment of pesticides. In this study, the toxicity of cypermethrin-contaminating soil on adult and juvenile earthworms was assessed. Beside the acute and chronic tests, an avoidance response test was carried out. It was shown that the all-round toxicity from cypermethrin was weak on adult earthworms. Compared with adult earthworms, the toxicity of juvenile earthworms from cypermethrin especially chronic toxicity increased significantly. Growth and reproduction of earthworms appeared to be more severely affected by cypermethrin at juvenile stage than at adult stage. Applied at 10 mg/kg, cypermethrin had obvious adverse impact on the growth of juvenile earthworms, while 20 mg/kg, cypermethrin caused significant toxic effects in reproduction. The results also indicated that ecotoxicological risk assessment using only adult specimens may underestimate the effects of cypermethrin on soil invertebrate populations.

Toxicity assessment for chlorpyrifos-contaminated soil with three different earthworm test methods.

Earthworm toxicity tests are useful tools for terrestrial risk assessment but require a hierarchy of test designs that differ in effect levels (behavior, sublethal, lethal). In this study, the toxicity of chlorpyrifos contaminated soil on earthworms was assessed. In addition to the acute and chronic tests, an avoidance response test was applied. Earthworms were exposed to sublethal and lethal concentration of chlorpyrifos, and evaluated for acute toxicity, growth, fecundity and avoidance response after a certain exposure period. The test methods covered all important ecological relevant endpoints (acute, chronic, behavioral). Concentration of 78.91 mg/kg, chlorpyrifos caused significant toxic effects in all test methods, but at lower test concentrations, only significant chronic toxic effects could be observed. In present study, chlorpyrifos had adverse effect on growth and fecundity in earthworm exposed to 5 mg/kg chlorpyrifos after eight weeks. The avoidance response test, however, showed significant repellent effects at concentration of 40 mg/kg chlorpyrifos. For chlorpyrifos, concentration affecting avoidance response was far greater than growth and fecundity, it seemed likely that earthworms were not able to escape from pesticide-contaminated soil into the clean soil in field and hence were exposed continuously to elevated concentrations of pesticides.

[Study on solid phase extraction spectrophotometric determination of zinc with 2-(2-quinolylazo)-5-dimthylaminophenol].

A highly sensitive, selective and rapid method for the determination of zinc based on the rapid reaction of zinc(II) with 2-(2-quinolylazo)-5-dimthylaminophenol (QADMAP) and the solid phase extraction of zinc ion with anion exchange resin cartridge was developed. In the presence of pH 8.5 buffer solution and Triton X-100 medium, QADMAP can react with zinc(II) to form a stable 2 :1 complex (QADMAP:Zn(II)). The molar absorptivity is 1.22 x 10(5)L x moL(-1) x cm(-1) at 590 nm. Beer's law is obeyed in the range of 0-1.0 microg x mL(-1). The zinc ions in the samples can be enriched and separated by solid phase extraction with anion exchange resincartridge. Testing results show that recovery for zinc(II) was from 95% to 104%, and RSD was below 3%. This method was applied to the determination of zinc in water and food with good results.