Activities of Urease and Phosphatase in Integrated Vertical Flow Constructed Wetland and Purification Effect of Black and Malodorous River

[Objective]The activities of urease and phosphatase in integrated vertical flow constructed wetland and purification effect of black and malodorous river were studied.[Method]Honeycomb stone and soft filler were used as matrix,the biological grid integrated vertical flow constructed wetland system was built to strengthen treatment for black and malodorous river,and the activities of urease and phosphatase of two fillers in different functional areas of constructed wetland were tested to study the film formation property of two fillers in different functional areas.[Result]Both urease and phosphatase activities on biofilm of soft filler were significantly higher than on biofilm of honeycomb stone filler;indicating that choosing soft filler was more advantageous to the growth of biofilm;and urease activity had significant correlation with total nitrogen removal rate,while phosphatase activity had no significant correlation with total phosphorus removal rate.[Conclusion]This study provided evidences for utilizing the activities of urease and phosphatase to evaluate the purification effect of black and malodorous river and choose appropriate filler.

Effect of Inhabitation Mouthwash Solution Containing Chlorine Dioxide (Pro Fresh^®) on Oral Malodor

Recently, the interest in oral malodor has been grown and the number of people having trouble with oral malodor is increasing year by year. Generally, as the branch of medicine which deals with patients complaining about oral malodor, dentistry is mostly chosen. On the current situation, however, the dental office side typically finds it difficult to deal with several kinds of oral malodor which show no improvement even though cavities or periodontal disease is completely cured. Main components to cause oral malodor are volatile sulfur compounds (methyl mercaptan, dimethyl sulfide, hydrogen sulfide);in the present study, therefore, the effect of mouthwash solution containing chlorine dioxide to relieve oral malodor and increase saliva production was tested. The subjects were 92 patients (Control group: 2 males, 3 females, age;30.8 ± 4 years old, Mouthwash group: 28 males, 59 females, age: 36.9 ± 1.3 years old) who visited the hospital complaining about oral malodor. Intraoral gas, exhaled gas, the saliva production at rest, the ability for salivation and the buffering ability of saliva were examined twice, before the subjects used the mouthwash solution every day for one month. The simple chromatography oral chroma, which was insulated from the influence of temperature and humidity and also was able to measure with a high degree of accuracy, was used to measure odor as the device analysis method. The control group did not change in VSCs, saliva production and the buffering ability of saliva. After using mouthwash solution, the concentration of the 3 major components gas of intraoral gas and exhaled gas, i.e. methyl mercaptan, dimethyl sulfide, hydrogen sulfide, were all decreased. As for hydrogen sulfide, intraoral gas (from 225.8 ± 28.1 ppb to 41.1 ± 8.8 ppb) and exhaled gas (from 212.0 ± 50.4 ppb to 34.6 ± 16.6 ppb) was significantly decreased. Also, saliva production at rest (from 1.3 ± 0.1 ml to 1.7 ± 0.1 ml) and the ability to salivate (from 4.5 ± 0.3 ml to 5.1 ± 0.3 ml) were both significantly increased. As for the buffering ability of saliva, significant changes were not detected on the change of salivary pH after using mouthwash solution, and it did not have any effects on the buffering ability of saliva. In conclusion, these results suggest that the mouthwash solution containing chlorine dioxide has significant effects on inhibiting malodor.

Researches on the In Situ Copolymerization of Ethylene with Catalysts Immobilized onto the Molecular Sieves

In this paper,the bi-functional catalyst system composed of molecular sieve（MCM-41） immobilized oligomerization catalyst（C25H17Cl2N3·FeCl2） and copolymerization catalyst（Et（Ind）2ZrCl2） was employed in the in situ copolymerization of ethylene aiming to prepare the Linear low density polyethylene（LLDPE）.In this paper,we mainly argued the regular pattern of the in situ copolymerization of ethylene in limited nano-space and compared it with that happening in free space.The impact of variance of the reaction temperature,Fe/Zr value and the A1/（Fe＋Zr） value on the activity of the in situ copolymerization of ethylene has also been introduced.Furthermore,the degree of branching,thermal properties and crystalline changes of the obtained polymerization products prepared from different reactivity were investigated.

Study on Ecological Governance Path of Rivers in the Tourist Town: Taking a Town in Jieyang of Guangdong as an Example

With the rapid development of urbanization,the pollution problem of rivers in cities and towns appears,which seriously affects life quality of residents around rivers.In this paper,rivers in one tourist town of Jieyang,Guangdong is taken as a research object,and pollution of inland rivers is analyzed and evaluated from industry,life and agriculture.Comprehensive improvement of ecological environment of inland rivers is conducted by combining pollution control engineering measures with ecological landscape construction.Eco-landscape rivers construction is the development trend of current rivers regulation.Combining cases of inland rivers control,ecological governance path of rivers water environment in tourist town is studied,which could provide the reference for ecological governance and landscape construction of urban rivers.

The Influence of Oral Malodor on Psychological Stress

We examined the influence of oral malodor on psychological stress among patients with a chief complaint of oral malodor. A total of 101 patients (40 male and 61 female) who visited our clinic with a chief complaint of oral malodor were included in this study. The primary compounds of oral malodor—volatile sulfur compounds (VSC)—were measured using the Oral ChromaTM instrument. Salivary stress markers, cortisol, and chromogranin A were measured using an enzyme-linked immunosorbent assay (ELISA) kit. The mood was measured using the Profile of Mood States 2nd Edition (POMS2). Among the participants, 60.3% had at least one level above the threshold in the following three markers: hydrogen sulfide, methyl mercaptan, and dimethyl sulfide. The gender distribution was 35 female (57.4%) and 25 male (62.5%). Salivary cortisol levels, a biomarker of stress, did not vary depending on the presence or absence of oral malodor. Chromogranin A levels were higher in the oral malodor female group than in the no oral malodor female group. With respect to the POMS2, regardless of the presence or absence of oral malodor measured using gas chromatography, the participants had higher scores for “Anger-Hostility” and “Fatigue-Inertia”. Analysis by gender showed that “Depression-Dejection” was significantly higher in the oral malodor female group than in the no oral malodor female group. These results suggest that those who are worried about oral malodor have higher psychological stress than those who are not, regardless of the presence or absence of oral malodor measured using gas chromatography.

Barrier Effect of a Membrane on Malodorous Gases

After the experimental research on the barrier effect of PTFE membrane on malodorous gases,it was found that PTFE membrane had good gas permeability,and the barrier effect on malodorous gases NH3 and H2S was poor. After a layer of water film was formed on PTFE membrane,it had an obvious barrier effect on malodorous gases NH3 and H2S.

Efficacy of a triclosan/copolymer dentifrice and a toothbrush with tongue cleaner in the treatment of oral malodor: A monadic clinical trial

Aim: Oral malodor (halitosis) is a widespread condition caused by oral bacteria, particularly sulfur compound-producing species. This study assessed the effect of a triclosan/copolymer-containing dentifrice and a novel toothbrush with attached tongue cleaner on oral malodor and on the bacteria colonizing the dorsal surface of the tongue. Materials and Methods: 14 adult subjects with oral malodor defined as organoleptic scores ≥ 3 (scale 0 - 5) and mouth air sulfur levels ≥ 250 ppb participated in this study. Subjects were examined at baseline and after 28 days use of the triclosan dentifrice and toothbrush/tongue cleaner for: 1) organoleptic assessment;2) mouth air sulfur levels;3) tongue coating;and, 4) dorsal tongue surface microorganisms. Total bacterial numbers were assayed by microscopy. Dot-blot hybridization was used to assess a panel of 20 oral bacteria. Results: After 28 days, all subjects had significantly reduced organoleptic scores and mouth air sulfur levels compared to baseline (p 70% reduction in microbial numbers (p Enterococcus faecalis (p Peptostreptococcus micros (p Prevotella melaninogenica (p Porphyromonas gingivalis (p Solobacterium moorei

Regulation of toxins and bioregulators under the Chemical Weapons Convention and the Biological and Toxin Weapons Convention

In this paper we highlight how the apparent double coverage of toxins and bioregulators by both the Biological and Toxin Weapons Convention(BTWC)and the Chemical Weapons Convention(CWC)in fact masks a regulatory gap that has left such potentially dangerous agents neglected by both the control regimes during a period of rapid advances in relevant chemical,life and associated sciences and technologies.We first review what toxins,bioregulators and other mid-spectrum agents are and why they are of such concern and then examine how they are regulated under the BTWC and CWC.This paper then examines an illustrative range of contemporary chemical and life science research and associated activities of concern drawn from case study research on China,India,Iran,Russia,Syria and the United States,and assesses how the CWC and BTWC States Parties have inadequately addressed these threats.We then examine how both the CWC and BTWC Review Conferences failed to address these long-term challenges,and we end by providing a series of recommendations for how both regimes can be strengthened in this area.