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Formation and speciation of disinfection byproducts during chlor(am)ination of aquarium seawater

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Journal of Environmental sciences 2015年第7期27卷 116-124页

作者： Haiting Zhang Huiyu Dong craig Adams Zhimin Qiang Gang Luan Lei Wang Key Laboratory of Drinking Water science and Technology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Department of Civil and Environmental Engineering Utah State University Water Quality Analysis and Control Center Department of Life Support Equipments for Aquatic AnimalsBeijing Aquarium

The chemistry associated with the disinfection of aquarium seawater is more complicated than that of freshwater, therefore limited information is available on the formation and speciation of disinfection byproducts（DBPs） in marine aquaria. In this study, the effects of organic precursors, bromide（Br-） and pre-ozonation on the formation and speciation of several typical classes of DBPs, including trihalomethanes（THM4）, haloacetic acids（HAAs）,iodinated trihalomethanes（I-THMs）, and haloacetamides（HAc Ams）, were investigated during the chlorination/chloramination of aquarium seawater. Results indicate that with an increase in dissolved organic carbon concentration from 4.5 to 9.4 mg/L, the concentrations of THM4 and HAAs increased by 3.2-7.8 times under chlorination and by 1.1-2.3 times under chloramination. An increase in Br-concentration from 3 to 68 mg/L generally enhanced the formation of THM4, I-THMs and HAc Ams and increased the bromine substitution factors of all studied DBPs as well, whereas it impacted insignificantly on the yield of HAAs. Pre-ozonation with 1 mg/L O3 dose substantially reduced the formation of all studied DBPs in the subsequent chlorination and I-THMs in the subsequent chloramination. Because chloramination produces much lower amounts of DBPs than chlorination, it tends to be more suitable for disinfection of aquarium seawater.

关键词： Disinfection byproducts Chlorination Chloramination Pre-ozonation Bromine substitution factorAquarium seawater

Community analysis of ammonia-oxidizing bacteria in activated sludge of eight wastewater treatment systems

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Journal of Environmental sciences 2010年第4期22卷 627-634页

作者： Xiaohui Wang Xianghua Wen craig Criddle George Wells Jie Zhang Yin Zhao Department of Environmental science and Engineering Tsinghua University Beijing 100084 China. Department of Civil and Environmental Engineering Jerry Yang & Akiko Yamazaki Environment & Energy Building Stanford University Stanford CA94305-4020 USA Beijing Drainage Group Co. Ltd. Beijing 100084 China

We investigated the communities of ammonia-oxidizing bacteria （AOB） in activated sludge collected from eight wastewater treatment systems using polymerase chain reaction （PCR） followed by terminal restriction fragment length polymorphism （T-RFLP）, cloning, and sequencing of the α-subunit of the ammonia monooxygenase gene （amoA）. The T-RFLP fingerprint analyses showed that different wastewater treatment systems harbored distinct AOB communities. However, there was no remarkable difference among the AOB T- RFLP profiles from different parts of the same system. The T-RFLP fingerprints showed that a full-scale wastewater treatment plant （WWTP） contained a larger number of dominant AOB species than a pilot-scale reactor. The source of influent affected the AOB community, and the WWTPs treating domestic wastewater contained a higher AOB diversity than those receiving mixed domestic and industrial wastewater. However, the AOB community structure was little affected by the treatment process in this study. Phylogenetic analysis of the cloned amoA genes clearly indicated that all the dominant AOB in the systems was closely related to Nitrosomonas spp. not to Nitrosospira spp. Members of the Nitrosomonas oligotropha and Nitrosomonas communis clusters were found in all samples, while members of Nitrosomonas europaea cluster occurred in some systems.

关键词： activated sludge ammonia-oxidizing bacteria T-RFLP amoA gene wastewater treatment plant

Case studies of earthquake-induced effects on concrete channels

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Earthquake science 2010年第1期23卷 63-69页

作者： craig A Davis Jianping Hu Jean-Pierre Bardet Los Angeles Department of Water andPower Los Angeles CA 90012 USA Civil and Environmental Engineering Department University of Southern California Los Angeles CA 90089 USA

Case studies are presented for two concrete lined channels shaken by strong ground motions during the 1994 Northridge earthquake, the high speed channel （HsC） and bypass channel （BC）, on the Los Angeles Department of Water and Power＇s Van Norman Complex. Performances of these two channels as they pass through different subsurface materials identify several important seismic aspects and the critical role of geotechnical earthquake engineering in assessing channel behaviors. Preliminary evaluations using detailed mapping of channel cracks, permanent ground movements, subsurface profiles, and nearby strong ground motion recordings from the 1994 earthquake show that the channel liners may have been damaged from both transient motions and permanent ground movements. Damage from permanent ground deformations is obvious by observation; therefore simplified analyses are presented only for transient movements. site specific transient response analyses are performed to provide an initial assessment of the differing effects from transient and permanent ground movements on HsC and BC liner damage. These case studies are helpful for introducing the potential for lifeline damage from transient movements within zones of permanent ground movement, a concept not well understood in the earthquake engineering community

关键词： concrete channel ground motion ground deformation transient movement lifeline

The genetic polymorphism of Plasmodium vivax genes in endemic regions of Thailand

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Asian Pacific Journal of Tropical Medicine 2011年第12期4卷 931-936页

作者： Varakorn Kosaisavee Ian Hastings Alister craig Usa Lek-Uthai Department of Parasitology and Entomology Faculty of Public HealthMahidol UniversityBangkokThailand Faculty of Graduate studies Mahidol University.NakornpathomThailand Department of Molecular and Biochemical Parasitology.Liverpool school of Tropical Medicine Pembroke PlaceLiverpoolUK

Objective:To investigate the genetic polymorphism of Plasmodium vivax(***) PvCsP and PvMsP1 genes from field isolates at four endemic regions(North,East,West and south) of ***:The 152 *** injected cases from dried blood spots were DMA extracted and confirmed by species-specific primer sets using multiplex PCR *** fragments F2 and F3:PvCsP were gcnotvped using RFLP-PCR ***:Totally amplified DNA which was multiple genotypes for PvMsP1 F2 and PvMsP1 F3 were 12.50%and 8.55%.respectively while PvCsP was 3.95%.The overall frequency of multiple genotypes was 25%.There were 12 allele tvpes of PvMsP1 F2 using AluI enzyme digestion and 8 size variations were found in P\MsP1 *** isolates from western region was highly genetic diverse when compare among all *** predominant variant type of PvCsP gene was \ K2I0 ***:The niulliple genotypes are common found in Thailand and it might hide the real *** does not have extensive genetic diversity in this *** marker due to multiple genotypes is difficult In be *** multiple genotypes findings might stem from population migration and vector species findings.

关键词： Genetic polymorphism Plasmodium vivax PvMsP1 PvCsP

Could titin have a role in strain-induced injuries？

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Journal of sport and Health science 2017年第2期6卷 143-144页

作者： craig Perrin Kazunori Nosaka James steele school of sport Health and Social SciencesSouthampton Solent University Ringgold Standard InstitutionSouthamptonS014 OYNUK school of Exercise and Health sciences Edith Cowan UniversityJoondalupWA 6027Australia

It has been known for some time that strain injuries occur through the excessive lengthening of a muscle.^(1–3)However,the precise mechanism for strain injury remains elusive and has been the subject of recent debate in the Journal of sport and Health science,^(4–9)but it seems sensible to consider mechanisms at the level of the muscle *** was previously believed that damage was the result of non-uniform stretching of

关键词：肌联蛋白损伤机制应变诱导肌肉纤维最佳长度肌原纤维最大变形力曲线

Inactivation of Cryptosporidium by ozone and cell ultrastructures

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Journal of Environmental sciences 2010年第12期22卷 1954-1959页

作者： Zhilin Ran shaofeng Li Junli Huang Yixing Yuan Chongwei Cui craig Denver Williams school of Municipal & Environmental Engineering Harbin Institute of Technology Harbin 150090 China Department of Building & Environmental Engineering Shenzhen Polytechnic Institute Shenzhen 518055 China school of Applied science University of Wolverhampton Wolverhampton WV1 1LY UK

The fluorescence staining method and scanning electron microscopy （sEM） were used to study the effect of ozone （O3） inactivating Cryptosporidium in water and cell ultrastructures variation to shed light on the mechanism of inactivation preliminarily. Results indicated that O3 had a stronger inactivating capability. When the concentration of O3 was above 3.0 mg/L and the contact time was up to 7 min, a significant inactivating effect could be achieved. The turbidity on inactivation effects was also found to be statistically significant in artificial water. With increases in turbidity, the inactivating effect decreased. Inactivation rate improved with a temperature increase from 5 to 25℃, but decreased beyond this. The inactivating capability of O3 was found to be stronger under acidic than that under alkalic conditions. When the concentration of organic matter in the reaction system was increased, the competition between Cryptosporidium and organics with O3 probably took place, thereby reducing the inactivation rate. In addition, the cellular morphology of Cryptosporidium varied with different contact times. At zero contact time, cells were rotundity and sphericity, at 60 sec they became folded, underwent emboly, and burst at 480 sec, the cell membrane of Cryptosporidium shrinked and collapsed completely.

关键词： ozone inactivation Cryptosporidium ultrastructures

POLYMERAsE CHAIN REACTION IN DETECTION OF HUMAN PAPILLOMAVIRUs DNA AND TYPEs OF CONDYLOMA ACUMINATA

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中华医学杂志(英文版) 1993年第2期106卷 141-144页

作者：朱文元 craig Leonardi Neal s.Penneys Department of Dermatology Nanjing Medical CollegeNanjing 210029 Department of Dermatology and Cutaneotls surgery University of Miami School of MedicineMiamiFlorida 33101USA Department Of Dermatology and Cutaneous surgery University of Miami School of MedicineMiamiFlorida 33101USA

sections from 88 paraffin-embedded tissues identifiedhistopathologically as condyloma acuminata were assayed forthe presence of human papillomavirus (HPV) types 6,11,16,18 and 33 using polymerase chain reaction followed by *** DNA sequences were found in all tissuesof condyloma *** type 6 was present in 71tissues,type 11 in 16,and type 16 in *** man was doublyinfected with HPV types 6 and *** HPV types 18 and 33were *** conclude that condyloma acuminata is mainlyproduced by HPV types 6 and 11.

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Risk factors affecting the Barrett's metaplasia-dysplasia-neoplasia sequence

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World Journal of Gastrointestinal Endoscopy 2015年第5期7卷 438-445页

作者： craig s Brown Michael B Ujiki Pritzker school of Medicine Biological Sciences Division University of Chicago Department of surgery North Shore University Health Systems

Esophageal adenocarcinoma has the fastest growing incidence rate of any cancer in the United states, and currently carries a very poor prognosis with 5 years relative survival rates of less than 15%. Current curative treatment options are limited to esophagectomy, a procedure that suffers from high complication rates and high mortality rates. Metaplasia of the esophageal epithelium, a condition known as Barrett's esophagus(BE), is widely accepted as the precursor lesion for adenocarcinoma of the esophagus. Recently, radiofrequency ablation has been shown to be an effective method to treat BE, although there is disagreement as to whether radio-frequency ablation should be used to treat all patients with BE or whether treatment should be reserved for those at high risk for progressing to esophageal adenocarcinoma while continuing to endoscopically survey those with low risk. Recent research has been targeted towards identifying those at greater risk for progression to esophageal adenocarcinoma so that radio-frequency ablation therapy can be used in a more targeted manner, decreasing the total health care cost as well as improving patient outcomes. This review discusses the current state of the literature regarding risk factors for progression from BE through dysplasia to esophageal adenocarcinoma, as well as the current need for an integrated scoring tool or risk stratification system capable of differentiating those patients at highest risk of progression in order to target these endoluminal therapies.

关键词： Barrett's esophagus Esophageal adenocarcinoma Endoscopy Risk factors Radiofrequencyablation Antireflux surgery

In vitro investigation of the effect of dairy propionibacteria on rumen pH,lactic acid and volatile fatty acids

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Journal of Integrative Agriculture 2017年第7期16卷 1566-1575页

作者： Jianbiao Luo Chaminda senaka Ranadheera stuart King craig Evans surinder Baines school of Environmental&Life sciences The University of NewcastleCallaghan NSW 2308Australia Advanced Food systems Research Unit College of Health and BiomedicineVictoria UniversityMelbourne VIC 3030Australia school of Health sciences The University of NewcastleCallaghan NSW 2308Australia

Ruminal acidosis is a prevalent disorder in ruminants such as dairy cows and feedlot beef cattle, caused primarily by the inclusion of a high percentage of readily fermentable concentrates in the diet. The disorder presents as an accumulation of lactic acid, a decrease of pH in the rumen and a subsequent imbalance of the rumen fermentation process with detrimental impacts on the animal＇s health and productivity. Dairy propionibacteria, a group of bacteria characterised by utilization of lactic acid as the favoured carbon source, with propionic acid produced as a by-product, were evaluated in this study as potential direct-fed microbials for use in controlling ruminal acidosis. Acidosis was simulated by introduction of high concentrations of lactic acid into rumen fluid samples and a multi-strain in vitro analysis was conducted, whereby changes in pH and lactic acid metabolism were compared in identical acidified rumen samples, following inoculation with various propionibacteria. This was followed by a study to evaluate the effect of bacterial inoculation dosage on acid metabolism. The results indicated that lactic acid levels in the rumen fluid were significantly reduced, and propionic acid and acetic acid concentrations both significantly increased, following addition of propionibacteria. significant ＇between strains＇ differences were observed, with Propionibacterium acidopropionici 341, Propionibacterium freudenreichfi CsCC 2207, Propionibacterium jensenfi NCFB 572 and P. jensenii 702 each producing more rapid reduction of lactic acid concentration than P. freudenreich# CsCC 2206, P. acidopropionici ATCC 25562 and Propionibacterium thoenii ATCC 4874. Furthermore, the efficacy of this application was dosage related, with the rates of reduction in lactic acid levels and production of propionic acid, both significantly greater for the higher （10^10 cfu mL-1） compared with lower （10^5 cfu mL-1） dosage inoculation. The results confirmed that the introduction of propion

关键词： probiotics ruminal acidosis lactic acid propionic acid dairy Propionibacterium