Quantitative source apportionment of dissolved organic matters in wet weather overflows of storm drainage systems based on degradation potential index and end member mixing model

Dissolved organic matter (DOM) in wet weather overflows (WWFs) of storm drainage systems mainly originates from anthropogenic sources, such as paved runoff, illegally discharged domestic sewage and the retained sediment. This study provides a promising method to quantitatively apportion the WWF DOM of storm drainage systems using degradation potential index (DPI) and end member mixing (EMM) model. DPI is derived from excitation-emission matrix parallel factor analysis (EEM-PARAFAC), which can endow the end members and itself of WWF DOM with numerical features, and thus help quantify the source contributions of WWF DOM in EMM model. Findings show that (1) DPI was a reliable tool in the quantitative source apportionment of WWF DOM, owing to its features of small variance within source and large variances between sources; (2) DPI combined with EMM model could help identify the factors that induce significant impacts on the source contributions of WWF DOM, such as the storm pumping discharge and antecedent dry days in our case study; (3) the identified factors could guide the development of effective strategies for WWF DOM control, e.g. sediment management in our case.

Complexing characteristics between Cu(Ⅱ) ions and dissolved organic matter in combined sewer overflows: Implications for the removal of heavy metals by enhanced coagulation

Enhanced coagulation has been widely used in storm tanks to remove heavy metal ions (HMs) from combined sewer overflows (CSOs), but faces challenges on removing the HMs bound to dissolved organic matter (DOM) with small molecular weight (MW). DOM ubiquitously existing in CSOs generally contains a large distribution range of MW, which can significantly impact the MW distribution of HMs by complexing reaction, thereby adding uncertainties for the removal efficiency of coagulation. Therefore, realizing the potential MW distribution of the HMs bound to CSO-DOM is greatly important for cost-effectively removing HMs from CSOs in the coagulation process. This paper presents a comprehensive approach of ultrafiltration, fluorescence quenching titration, excitation-emission matrix parallel factor analysis, complexation model, and two-dimensional correlation fluorescence spectroscopy for exploring the MW-based complexing characteristics between Cu(II) ions and CSO-DOM components. Results show that: (1) Cu(II) ions that bound to the CSO-DOM were mainly distributed in the MW range of <5 kDa, which makes them very difficult to be removed from CSOs by coagulation technique. (2) Concentration effect and molecular composition exerted great impacts on the MW distribution of the Cu(II) ions bound to CSO-DOM. (3) The humic-like component of terrestrial origin with the MW range of 100 kDa∼0.45 μm possessed high binding stability, capacity, and priority with Cu(II) ions, and they could be used at a high concentration to promote the removal efficiency of coagulation for Cu(Ⅱ) ions of CSOs by competitive complexation and inter-molecular bridging.

[Efficacy and tolerance of Memantine monotherapy and combination therapy with Reinhartdt And Sea Cucumber Capsule on agitation in moderate to severe Alzheimer disease]

Objective: To explore the efficacy and tolerance of Memantine combined Reinhartdt And Sea Cucumber Capsule (R.S.C) on treating agitation in patients with moderate-severe Alzheimer disease (AD). Methods: One hundred and fifty-eight moderate-sever AD patients from Sep.2013 to Sep.2014 in Zhejiang Provincial People's Hospital were randomly divided into two groups: group of Memantine combined R. S.C and group of single Memantine. Then Mini-Mental Sate Examination (MMSE) and Neuropsychiatric Inventory (NPI) were used to evaluate cognition symptom, behavioral and psychological symptoms of dementia (BPSD) and agitation symptom at the baseline and the end of 24 weeks.The Treatment Emergent Symptom Scale (TESS) was used to assess adverse reaction and tolerance.At last, the data was analyzed by chi-square test, t-test and covariance test. Result: At the terminal of experience, the total NPI scores and agitation factor decreased markedly in both of the two groups (P<0.05). Among the patients who had agitation symptom at the baseline, the total NPI scores and agitation factor (18±5, 3.7±2.6) in group of Memantine combined R. S.C were notably lower than those in the group of single Memantine (21±6, 5.3±2.5) (P<0.05). The incidence of adverse reaction between the two groups had no significant difference (combined treatment group was 27.7%, single treatment group was 23.2%). One patient dropped out because of skin allergy, and most adverse reactions were tolerant. Conclusions: Both two groups are effective in agitation and BPSD, and Memantine combined R. S.C is better than single treatment.R.S.C dose not aggravate adverse reaction and can be well tolerated.

Anthropogenic Influences of Paved Runoff and Sanitary Sewage on the Dissolved Organic Matter Quality of Wet Weather Overflows: An Excitation-Emission Matrix Parallel Factor Analysis Assessment

The quality of dissolved organic matter (DOM) in a wet weather overflow (WWF) can be broadly influenced by anthropogenic factors, such as nonpoint sources of paved runoff and point sources of sanitary sewage within the drainage networks. This study focused on the anthropogenic influences of the paved runoff and sanitary sewage on the DOM quality of WWF using excitation-emission matrix parallel factor analysis (EEM-PARAFAC). Results show that (1) EEM-PARAFAC fitted terrestrial humic-like, anthropogenic humic-like, tryptophan-like, and tyrosine-like components can be regarded as indicators to identify the types of sewage overflows and the illicit connection status of drainage systems. (2) A short emission wavelength (em: 302-313 nm) peak of the tyrosine-like component occurred in the reserved sanitary sewage, while a type of longer emission wavelength (em: 321-325 nm) peak came from the sump deposit. These tyrosine-like components were gradually evacuated in the initial phase of the overflow process with the fading of their EEM signals. Fluorescence signal transformations of all the components confirmed the potential ability of EEM-PARAFAC to monitor the dynamic changes of the primary pollutant sources. (3) The input of the newly increased sanitary sewage had a dominant influence on the quality and yield of the WWF DOM.

Combination of powdered activated carbon and powdered zeolite for enhancing ammonium removal in micro-polluted raw water

Even zeolite is promising in ammonia pollution disposing, its removal efficiency is frequently interfered by organics. As activated carbon has good removal efficiency on organic contaminants, combination of two adsorbents may allow their respective adsorption characteristics into full play. This paper provides a performance assessment of the combination for enhancing ammonium removal in micro-polluted raw water. Gel-filtration chromatography (GFC) was carried out to quantify the molecular weight (MW) range of organic contaminants that powdered activated carbon (PAC) and powdered zeolite (PZ) can remove. The polydispersity difference which also calculated from GFC may indicate the wider organic contaminants removal range of PAC and the relatively centralized removal range of PZ. The jar tests of combination dosing confirm a synergistic effect which promotes ammonium removing. Nevertheless, it also shows an antagonism hindering the due removal performance of the two adsorbents on CODMn, while it is not much evident on UV254. Furthermore, a comparison study with simulated coagulation-sedimentation process was conducted to evaluate the optimum dosing points (spatial and temporal) of PAC and PZ among follows: suction well, pipeline mixer, early and middle phase of flocculation. We suggest to dose both two adsorbents into the early phase of flocculation to maximize the versatile removal efficiency on turbidity, ammonium and organic contaminants.

Combined sewer overflow control with LID based on SWMM: an example in Shanghai, China

Although low impact development (LID) has been commonly applied across the developed countries for mitigating the negative impacts of combined sewer overflows (CSOs) on urban hydrological environment, it has not been widely used in developing countries yet. In this paper, a typical combined sewer system in an urbanized area of Shanghai, China was used to demonstrate how to design and choose CSO control solutions with LID using stormwater management model. We constructed and simulated three types of CSO control scenarios. Our findings support the notion that LID measures possess favorable capability on CSO reduction. Nevertheless, the green scenarios which are completely comprised by LID measures fail to achieve the maximal effectiveness on CSO reduction, while the gray-green scenarios (LID measure combined with gray measures) achieve it. The unit cost-effectiveness of each type of scenario sorts as: green scenario > gray-green scenario > gray scenario. Actually, as the storage tank is built in the case catchment, a complete application of green scenario is inaccessible here. Through comprehensive evaluation and comparison, the gray-green scenario F which used the combination of storage tank, bio-retention and rain barrels is considered as the most feasible one in this case.

Analysis on LID for highly urbanized areas' waterlogging control: demonstrated on the example of Caohejing in Shanghai

Although a commonly applied measure across the United States and Europe for alleviating the negative impacts of urbanization on the hydrological cycle, low impact development (LID) has not been widely used in highly urbanized areas, especially in rapidly urbanizing cities in developing countries like China. In this paper, given five LID practices including Bio-Retention, Infiltration Trench, Porous Pavement, Rain Barrels, and Green Swale, an analysis on LID for highly urbanized areas' waterlogging control is demonstrated using the example of Caohejing in Shanghai, China. Design storm events and storm water management models are employed to simulate the total waterlogging volume reduction, peak flow rate reduction and runoff coefficient reduction of different scenarios. Cost-effectiveness is calculated for the five practices. The aftermath shows that LID practices can have significant effects on storm water management in a highly urbanized area, and the comparative results reveal that Rain Barrels and Infiltration Trench are the two most suitable cost-effective measures for the study area.

Clinical and experimental study on therapeutic effect of Weixibaonizhuanwan on gastric precancerous lesions

AIM

To study the therapeutic effect of Weixibaonizhuanwan on gastric precancerous lesions.

METHODS

Thirty-six patients with gastric precancerous lesions were treated with Weixibaonizhuanwan for 3 mo. Thirteen (36.1%) patients presented with mild atrophic gastritis, 14 (38.9%) with moderate atrophic gastritis, and nine (25.0%) with severe atrophic gastritis. Twenty-two (61.1%) and 27 (75.0%) of the cases were accompanied by intestinal metaplasia (IM) and dysplasia (DYS), respectively. Twenty of the 36 patients were men and 16 were women, ranging from 30 to 67 years in age, with 61.1% of the patients being 40-59 years old. The duration of the disease in these patients ranged from 3 mo to 21 years, with 20 (55.6%) patients experiencing durations of the disease between 5 and 10 years. The clinical manifestations of the disease in these patients included fullness of the abdomen (31 cases), abdominalgia (27 cases), anorexia (30 cases), eructation (26 cases), pantothenic acid (6 cases), and loose stool (9 cases). Patients were treated with Weixibaonizhuanwan and symptom improvement, level of atrophy of the gastric mucosa, and IM and DYS progression were analyzed.

RESULTS

After a 3-mo treatment with Weixibaonizhuanwan, seven patients experienced recovery. The treatment was effective in 11 cases, improved symptoms in 13 cases, and was ineffective in five cases. The overall efficacy rate was 86.1%. In patients with mild atrophic gastritis (n = 13), 11 improved into superficial gastritis and two experienced no improvement. In 14 cases of moderate gastritis, four cases improved into superficial gastritis and seven turned into mild atrophic gastritis, with three patients experiencing no improvement. Among severe atrophic gastritis patients (n = 9), five improved into moderate atrophic gastritis after treatment and four experienced no improvement. The overall efficacy rate in chronic atrophic gastritis patients was 77.8%. Among 9 patients with IM, IM disappeared in six cases, whereas three cases showed no improvement after treatment. In cases with moderate IM (n = 10), IM disappeared in two, turned into mild IM in five, and showed no change in three. Out of four cases with IM, one case turned into moderate IM and three showed no change. The overall efficacy rate in IM patients was 63.6%. Out of 16 cases of mild DYS, DYS disappeared in 11, whereas five cases showed no change. Out of nine cases of moderate DYS, DYS disappeared in two and turned into mild DYS in five cases, with two patients experiencing no change after treatment. No improvement was observed in the two cases of severe DYS after treatment. The overall efficacy rate in DYS patients was 66.7%. After treatment, expression of carcinoembryonic antigen (CEA) and proliferating cell nuclear antigen (PCNA) in gastric mucosa significantly decreased (P < 0.01). Before treatment, cancer staging of these patients by positive CEA expression was I, II, III, and IV in 13, 12, 9, and 2 cases, respectively. After treatment, the number of cases per stage changed to 25, 7, 3, and 1, respectively. Similarly, before treatment, staging by positivity of PCNA expression was I, II, III, and IV in 16, 11, 10, and 4 cases, respectively, and changed to 21, 9, 5, and 1, respectively, after treatment.

CONCLUSION

The use of Weixibaonizhuanwan in the treatment of gastric precancerous lesions showed promising therapeutic effects in patients after 3-mo treatments.