bluuebunny/crossref_metadata_2025 huggingface dataset:
Clinical relevance of mutations and gene-expression changes in adult acute myeloid leukemia with normal cytogenetics: are we ready for a prognostically prioritized molecular classification?
Authors: Mrózek Krzysztof , Marcucci Guido , Paschka Peter , Whitman Susan P. , Bloomfield Clara D.
Published: September 2006

Recent molecular analyses of leukemic blasts from pretreatment marrow or blood of patients with acute myeloid leukemia (AML) and a normal karyotype, the largest cytogenetic subset (ie, 40%-49%) of AML, have revealed a striking heterogeneity with regard to the presence of acquired gene mutations and changes in gene expression. Multiple submicroscopic genetic alterations with prognostic significance have been discovered, including internal tandem duplication of the FLT3 gene, mutations in the NPM1 gene, partial tandem duplication of the MLL gene, high expression of the BAALC gene, and mutations in the CEBPA gene. Application of gene-expression profiling has also identified a gene-expression signature that appears to separate cytogenetically normal AML patients into prognostic subgroups, although gene-expression signature-based classifiers predicting outcome for individual patients with greater accuracy are needed. These and similar future findings are likely to have a major impact on the clinical management of cytogenetically normal AML not only in prognostication but also in selection of appropriate treatment, since many of the identified genetic alterations already constitute or will potentially become targets for specific therapeutic intervention. In this report, we review prognostic genetic findings in karyotypically normal AML and discuss their clinical implications.
FAT 10, a gene up-regulated in various cancers, is cell-cycle regulated
Authors: Lim Chuan-Bian , Zhang Dongwei , Lee Caroline GL
Published: September 2006

Background

FAT10 is a member of the ubiquitin-like-modifier family of proteins. Over-expression of the FAT10 gene was observed in the tumors of several epithelial cancers. High FAT10 expression was found to lead to increased chromosome instability via the reduction in the kinetochore localization of MAD2 during the prometaphase stage of the cell-cycle. FAT10 expression was also previously reported to be regulated by cytokines and p53.

Results

Here, we report that FAT10 expression is regulated at the protein and transcript level during cell-cycle with highest expression observed during the S-phase of the cell-cycle. The distal region between -1997 to -975 bp from the transcription start site of the FAT10 promoter may play a role in the repression of FAT10 expression during G2/M phase of the cell-cycle.

Conclusion

FAT10 expression is regulated during cell-cycle.
Endotoxin tolerance attenuates LPS-induced TLR4 mobilization to lipid rafts: a condition reversed by PKC activation
Authors: Cuschieri Joseph , Billigren Jens , Maier Ronald V
Published: September 2006

Endotoxin tolerance is characterized by attenuated macrophage activation to subsequent LPS challenge and can be reversed through nonspecific protein kinase C (PKC) activation, and activation by LPS within naïve cells requires the activation of the cell surface receptors CD14 and TLR4 on lipid rafts. The effect of PKC activation and endotoxin tolerance on lipid raft receptor complex assembly is unknown and the focus of this study. Tolerance was induced in THP-1 cells through LPS pre-exposure. Naïve and tolerant cells were stimulated with LPS, with or without PMA pretreatment to activate PKC. TLR4 surface expression and LPS binding were determined by flow cytometry and immunohistochemistry. Cellular and lipid raft protein was analyzed for the presence and activation of the TLR4 complex components. Harvested supernatants were examined for TNF-α production. Total TLR4 surface expression and LPS binding were not affected by tolerance induction. LPS stimulation of naïve cells resulted in TLR4 and heat shock protein (HSP)70 lipid raft mobilization, MAPK activation, and TNF-α production. LPS stimulation of tolerant cells was associated with attenuation of all of these cellular events. Although PKC activation by PMA had no effect on naïve cells, it did result in reversal in tolerance-induced suppression of TLR4 and HSP70 lipid raft mobilization, MAPK activation, and TNF-α production. In addition, the effects associated with PMA were reversed with exposure to a myristoylated PKC-ζ pseudosubstrate. Thus, endotoxin tolerance appears to be induced through attenuated TLR4 formation following LPS stimulation. This complex formation appears to be PKC-dependent, and restoration of PKC activity reverses tolerance.
Prognostic Factors in Adenocarcinoma of the Esophagus or Gastroesophageal Junction
Authors: Lagarde Sjoerd M. , ten Kate Fiebo J.W. , Reitsma Johannes B. , Busch Olivier R.C. , van Lanschot J. Jan B.
Published: September 2006

The incidence of adenocarcinoma of the esophagus is rising rapidly in Western Europe and North America. It is an aggressive disease with early lymphatic and hematogenous dissemination. TNM cancer staging systems predict survival on the basis of the anatomic extent of the tumor. However, the adequacy of the current TNM staging system for adenocarcinoma of the esophagus or gastroesophageal junction (GEJ) is questioned repeatedly. Numerous prognostic factors have been described, but are not included in the TNM system. This review describes clinical parameters, aspects of operative technique, response to preoperative chemoradiotherapy therapy, complications and established pathologic determinants found in the resection specimen that have a prognostic impact. Furthermore, their potential application in the clinical setting in patients with adenocarcinoma of the esophagus or GEJ is discussed. Future directions to improve staging systems are given.
Role for Prostaglandins in the Regulation of Type 1 11β-Hydroxysteroid Dehydrogenase in Human Granulosa-Lutein Cells
Authors: Jonas Kim C. , Chandras Christina , Abayasekara D. Robert E. , Michael Anthony E.
Published: September 2006

11β-Hydroxysteroid dehydrogenase (11βHSD) enzymes regulate glucocorticoid availability in target tissues. 11βHSD1 is the predominant isoenzyme expressed and active in human granulosa-lutein (hGL) cells. This study investigated the effects of pharmacological inhibitors of prostaglandin (PG) synthesis on 11βHSD1 activities and expression in hGL cells. The consequences for 11βHSD1 of increasing exposure of hGL cells to PGs, either by treatment with exogenous PGs or by challenging cells with IL-1β, were also assessed. Suppression of basal PG synthesis using four different inhibitors of PG H synthase enzymes [indomethacin, niflumic acid, meclofenamic acid (MA) and N-(2-cyclohexyloxy-4-nitorophenyl) methane sulfonamide (NS-398)] each resulted in significant decreases in both cortisol oxidation and cortisone reduction. Both activities of 11βHSD1 were suppressed by up to 64 ± 6% (P < 0.05). Over 4 and 24 h, neither MA nor NS-398 affected the expression of 11βHSD1 protein, suggesting enzyme regulation by PGs at the posttranslational level. When cells were cotreated for 4 h with PGHS inhibitors plus 30 nm PGD2, PGF2α, or PGE2, each PG overcame the suppression of cortisol oxidation by indomethacin or MA. Treatment of hGL cells with IL-1β increased the concentrations of both PGE2 and PGF2α, accompanied by a 70 ± 25% increase in net cortisol oxidation. All three responses to IL-1β were abolished when cells were cotreated with MA. These findings suggest a role for PGs in the posttranslational regulation of 11βHSD1 activities in hGL cells.
Acute epiglottitis in adults
Authors: Hawkins Donald B. , Miller Alden H. , Sachs George B. , Benz Ronald T.
Published: September 2006

Epiglottitis occurs more frequently in adults than is generally realized. More than 100 adults with epiglottitis have been reported prior to this paper. Sixty‐two have been reported in the last 15 years. The mortality rate of these 62 patients was 32 percent. Tracheostomy was required in 45 percent of those who recovered.

Seventeen adults with epiglottitis have been managed at the Los Angeles County/University of Southern California Medical Center in the past 10 years; 13 of these were seen in the last four years. Most were males between 20 and 45 years of age. Four required tracheostomy. There were no deaths. An additional adult, treated at a neighboring hospital, who recovered from Hemophilus influenzae epiglottitis and meningitis is reported. He required tracheostomy for acute airway obstruction.

The following impressions can be derived from an anlysis of the literature and the patients discussed in this paper: 1. epiglottitis in adults has been reported more often in recent years. This may be due to increased awareness of this condition; or it may be due to actual increased incidence. 2. Epiglottis is more severe when due to Hemophilus influenzae, Type B than when due to other pathogens; and infections due to H. influenzae are being noted more frequently in adults. 3. The primary treatment of adult epiglottitis is: mist tent, intravenous antibiotics, and tracheostomy when indicated. Steroids may benefit some patients by slowing progression of epiglottic edema. 4. The symptoms of epiglottitis are sore throat, dysphagia, respiratory distress, and muffled voice. The characteristic early symptoms are sore throat and dysphagia. Any patient with acute painful dysphagia should have indirect laryngoscopy to rule out epiglottitis.
Isolated sphenoid sinus lesions
Authors: Wyllie John W. , Kern Eugene B. , Djalilian Mohsen
Published: September 2006

Forty‐five patients with isolated sphenoid sinus lesions were seen at the Mayo Clinic between 1935 and 1972. The types of lesions that these patients had included inflammatory lesions (chronic sphenoid sinusitis and mucopyoceles), tumors, fibrous dysplasia, rhinoliths, and sphenoid polyp. A review of the anatomy and important structures contiguous to the sphenoid sinus reflected the range and progression of clinical symptoms. Complications included pain or headache, visual disturbance including blurred vision, diplopia, exophthalmos, blindness, meningitis, and even death. The most frequent presenting symptoms were headache, retro‐orbital pain, nasal congestion, and visual disturbance, especially diplopia. Some time during the course of the illness, 40. percent of the patients developed visual involvement. Diagnosis was made with the aid of the patient's history and physical examination, whereas the laboratory studies usually were negative, and roentgenographic findings ranged from thickening to fluid levels and bony erosion or frank destruction of the floor of the sella. Fifteen percent of the roentgenograms were false‐negatives, all of which were noted in patients with inflammatory lesions. The differential diagnosis includes pituitary lesions, although the clinical features, the bitemporal hemianopsia, and hypopituitary function, which are characteristic of pituitary tumors, are absent in isolated sphenoid sinus lesions. Mild degrees of panhypopituitarism may exist with inflammatory lesions of the sphenoid sinus. Definitive diagnosis and therapy are usually effected by transnasal exploration of the sphenoid sinus.
Acquired nasopharyngeal stenosis
Authors: Pratt Loring W.
Published: September 2006

Acquired Nasopharyngeal Stenosis is a rare lesion. In the pre‐antibiotic era it was most commonly caused by infections, chiefly syphilis. Since improved control of infectious diseases has been obtained, the most common cause is nasopharyngeal surgery, primarily T and A. The symptoms are those of complete postnasal obstruction. Its treatment is surgical, utilizing various techniques, depending upon the precise nature of the lesion. The use of regional mucosal flaps is one of the most satisfactory methods of repair.
Cochlear otosclerosis: Fact or fantasy
Authors: Schuknecht Harold F. , Kirchner J.Cameron
Published: September 2006

Histological examination of 910 temporal bones from 582 individuals reveals 92 specimens with clinical otosclerosis (stapes fixation) and 32 with histological otosclerosis (without stapes fixation). The incidence of histological otosclerosis in ears from white individuals over the age of five (734 ears) was 4.4 percent. The otosclerotic focus involved the endosteum of the cochlear wall (cochlear otosclerosis) in three of the latter group for an incidence of 0.3 percent.

The atrophic changes in one of the ears with cochlear otosclerosis cannot be attributed to the otosclerosis, for the same changes are present in the other ear which does not have an otosclerotic focus; neither can the mild hearing loss in the other two ears showing cochlear otosclerosis be attributed to the otosclerosis, for the atrophic changes are identical to those observed in aging individuals without otosclerosis.

In conclusion, this study shows that sensori‐neural hearing loss occurring in pure form without a conductive loss cannot be attributed to otosclerosis, for when the otosclerotic lesion is sufficiently severe to cause atrophy of the supporting, sensory, and neural structures within the cochlea, it invariably also fixes the stapes.
Benign osteoblastoma of the temporal bone
Authors: Ronis Max L. , Obando Marcelo , Bucko Matthew I. , Liebman Emil P.
Published: September 2006

We have described a benign osteoblastic lesion in the middle ear in a 13‐year‐old boy who presented with a gradual hearing loss in the right ear. The patient also described a beating or pulsating sensation in the right ear without other symptoms. The examination of the right ear revealed a mass lesion which occupied the medial portion of the canal and seemed to be arising from and in continuity with the posterior inferior wall of the external canal. The benign osteoblastoma rarely has malignant characteristics. Based on the experience of others, partial removal of the lesion was carried out by curettage preserving the integrity of the middle ear space and facial nerve. This is probably the first case report of such a lesion involving the temporal bone in the middle ear and we found it to be a most interesting and thought provoking lesion both by virtue of its presentation and management.
Traumatic Brain Injury and Prospective Memory: An Examination of the Influences of Executive Functioning and Retrospective Memory
Authors: Kinch Julianne , McDonald Skye
Published: September 2006

This study investigated the effect of severe traumatic brain injury (TBI) on prospective memory. It also sought to identify the relative contributions of executive functioning and retrospective memory to prospective memory. Thirteen patients with severe TBI and 13 matched control subjects were assessed on two novel, yet ecologically valid, experimental measures of prospective memory and standard tests of neuropsychological functioning. Participants with TBI performed significantly worse than did controls on neuropsychological tests and a time-based prospective memory task, indicating that TBI affected not only retrospective but also prospective memory functioning. Multiple regression analyses identified relationships between executive functioning and time-based prospective memory and between retrospective memory and event-based prospective memory. Implications of these findings for the assessment and rehabilitation of memory impairment in individuals with TBI are discussed.
Duncan's Spearman's “G” — A New Measure of Executive Function?
Authors: Andrewes David
Published: September 2006

Duncan's theory allows that executive function may be represented by a central and general construct of intelligence which was originally described by Spearman (Spearman, 1946). This theoretical critique discusses the three planks of evidence which appear to support this proposal: (1), the finding that intra correlations between “executive” tests are low and in one study equivalent to those with non-executive tasks, (2), that tests which are seen as most representative of Spearman's G may be used to identify patients with frontal lobe lesions and executive dysfunction and (3), the finding that functional neuroimaging studies which have used disparate tasks may show a similar region of activation within the prefrontal cortex. The evidence for these three findings is discussed in terms of their ability to support Duncan's theory.
Development and Piloting of the Starship Posttraumatic Amnesia Scale for Children Aged Between Four and Six Years
Authors: Fernando Kris , Eaton Lynette , Faulkner Morag , Moodley Yogi , Setchell Raylene
Published: September 2006

The aim of this study was to develop and pilot a posttraumatic amnesia scale (PTA) scale for children aged between four and six years. The scale consists of seven orientation questions and five memory items modelled on the Westmead PTA Scale which assesses posttraumatic amnesia in children from eight years onwards and adults. The sample consisted of 45 four-year-olds, 82 five-year-olds and 49 six-year-old children from a variety of cultural and socioeconomic backgrounds. Children were recruited from hospitals, kindergartens and schools. Results were analysed across age groups using means and standard deviations. The orientation and memory items were analysed separately as well as in combination. Early analyses indicate that the majority of normal children in the four to 6 year age group can answer most of the orientation questions correctly and remember the memory stimuli from day to day. The results indicate that the Starship PTA Scale is suitable for young children aged 4 to 6 years. It is simple and quick to administer and utilises an operational definition of posttraumatic amnesia in terms of measuring continuous memory.
Point-of-care testing in the cardiovascular operating theatre
Authors: Nydegger Urs E. , Gygax Erich , Carrel Thierry
Published: September 2006

Point-of-care testing (POCT) remains under scrutiny by healthcare professionals because of its ill-tried, young history. POCT methods are being developed by a few major equipment companies based on rapid progress in informatics and nanotechnology. Issues as POCT quality control, comparability with standard laboratory procedures, standardisation, traceability and round robin testing are being left to hospitals. As a result, the clinical and operational benefits of POCT were first evident for patients on the operating table. For the management of cardiovascular surgery patients, POCT technology is an indispensable aid. Improvement of the technology has meant that clinical laboratory pathologists now recognise the need for POCT beyond their high-throughput areas.

Clin Chem Lab Med 2006;44:1060–5.
Lipid peroxidation and homocysteine levels in Behçet's disease
Authors: Mungan A. Görkem , Can Murat , Açikgöz Serefden , Eştürk Emel , Altinyazar Cevdet
Published: September 2006

Clin Chem Lab Med 2006;44:1115–8.
Exploring allelic imbalance within paraffin-embedded tumor biopsies using pyrosequencing technology
Authors: Pascual Manuel Hidalgo , Luis Royo José , Martínez-Tello Francisco Jose , Crespo Carmen , Salinas Ana , Herrero Eduardo Ferrero , Lopez-García María , Real Luis Miguel , Ruiz Agustín , Ramirez-Lorca Reposo
Published: September 2006

Clin Chem Lab Med 2006;44:1076–81.
Automated processing of whole blood samples for the determination of immunosuppressants by liquid chromatography tandem-mass spectrometry
Authors: Vogeser Michael , Spöhrer Ute
Published: September 2006

Clin Chem Lab Med 2006;44:1126–30.
A long and winding road: defining the biological role and clinical importance of paraoxonases
Authors: James Richard W.
Published: September 2006

Paraoxonase-1 (PON1) is an enzyme belonging to a three-member gene family, each of which is highly conserved in mammalian evolution. Whilst there is consensus that the paraoxonase family members have a general protective influence, their precise biological role has remained elusive. A toxicological role, protecting from environmental poisoning by organophosphate derivatives, drove much of the earlier work on the enzymes. More recently, clinical interest has focused on a protective role in vascular disease via a hypothesised impact on lipoprotein lipid oxidation. Recent confirmation that the primary activity of the paraoxonases is that of a lactonase considerably expands the potential sources of biological substrates for the enzyme. Studies on such substrates may shed further light on different mechanisms by which paraoxonases beneficially influence atherosclerosis, as well as defining possible roles in limiting bacterial infection and in innate immunity.

Clin Chem Lab Med 2006;44:1052–9.
Flow Friction Fire History and Research
Authors: Gallus TD , Stoltzfus JM
Published: September 2006

Fires in oxygen systems are most commonly attributed to flow dynamic ignition mechanisms such as particle impact and rapid pressurization heating. However, there have been fires in oxygen systems that could not be attributed to the most common ignition mechanisms. Some of these fires have been attributed to a poorly understood ignition mechanism for polymers, called “flow friction.” A brief history of fires attributed to flow friction is presented. In addition, the flow friction research that has been performed at NASA Johnson Space Center White Sands Test Facility is reviewed. Specifically, the possibility that flow friction is simple frictional heating powered by spontaneous gas-driven polymer oscillations is investigated. The results of the latest research on polymer fires based on spontaneous combustion assisted by frictional heat are presented.
Marketing urban water services: information needs for water utility managers in developing countries
Authors: Mugabi J. , Njiru C.
Published: September 2006

A decade ago the ‘Dublin Principles’ shifted global thinking towards treating water as an economic good. The concern was that overly supply-driven approaches had been financially unsustainable, and therefore failed to reduce the service gap. Accompanying this conceptual shift has been a wider move towards focusing on the customer's needs and preferences and their willingness to pay, and applying marketing techniques to meet those needs in a financially sustainable manner. Although regarded as a positive move, its success is heavily dependent on how well water utilities understand their customers. This paper examines existing literature on the determinants of customer willingness to use and pay for improved water services in developing countries. The contribution of past research to our understanding of the behaviour of customers, with regard to service level choice and payment for services, is critically analysed. Basing on this analysis, we develop and discuss a generic model of a water consumer's decision-making process. The model serves two purposes. First, it consolidates past research into a coherent framework to facilitate implementation of the marketing approach. Secondly, we use the model to identify critical customer information that water utility managers need to know in order to be customer-focused.
Sensory and chemical analysis methods for earthy and musty odours in drinking water caused by geosmin and 2-methylisoborneol
Authors: Wang Z. , Suffet I.H. , Al-Samarrai
Published: September 2006

Earthy and musty odours are amongst the most frequently observed objectionable odours in water supplies, and geosmin and 2-methylisoborneol are identified as the chemical compounds most closely associated with these odours. In this paper, the sensory properties, and the water matrix effects on taste and odour panel studies, as well as the chemical analysis methods for earthy and musty odours in drinking water caused by geosmin and 2-methylisoborneol, are reviewed. Insights are developed to enable better evaluation of earthy and musty odours in drinking water. Early detection of geosmin and MIB can prevent off-flavour occurrence by providing information for potential treatment.
Structure and function of slow release organic carbon source in groundwater in-situ denitrification
Authors: Zhang D.Y. , Li G.H. , Wang Y. , Zhou G.Z.
Published: September 2006

Many nitrate pollution cases exceed the threshold as recommended by the World Health Organization (50 mg NO3/L) and by the USA (10 mg N/L) for drinking water. In-situ denitrification was regarded as a good method to decrease nitrate contamination but is restricted by carbon absent in groundwater. Considering the disadvantages of known carbon sources, this paper provided slow-release organic carbon-source (SOC) technique to solve the problem and the results showed that SOC materials showed good performance during simulated groundwater denitrification. Structure analysis suggested that hydroxy chemical bond existed between PVA and starch in SOC and surface configuration changed with materials dissolving into water. After seven days of domestication, with 40–50 mg/L initial NO3-N, denitrification efficiency increased from 80.6% to 90.7% and the real COD consumption per N-NO3 reduction was 1.82–3.73 with 2.79 as average. Denitrification process followed the law of zero order kinetics and the parameter of denitrification dynamics, K, was from 0.1366 to 0.1873. It was suggested that SOC was a potential carbon source material (electron donor) suitable for in-situ groundwater denitrification.
Sonochemical decomposition of phenol: evidence for a synergistic effect of ozone and ultrasound for the elimination of total organic carbon
Authors: Lesko T. , Colussi A.J. , Hoffmann M.R.
Published: September 2006

The degradation of phenol (C6H5OH) was investigated under sonication, ozonation, and the combination of sonication and ozonation. The coupling of these two oxidation processes yielded phenol degradation kinetics that are similar to those predicted from the linear combination of the individual sonication and ozonation experiments. However, synergistic effects of sonolytic ozonation were observed for the reduction of the total organic carbon (TOC) in these systems. The rate of TOC decomposition was found to be proportional to both the aqueous steady-state ozone concentration and the ultrasonic power density. At 358 kHz, sonication combined with ozonation enhanced TOC loss rates by 43% over the sum of the rates obtained by the separate treatments. Intermediate species detected during the degradation of phenol indicate that while the primary degradation products are efficiently degraded by simple ozonolysis, the simultaneous addition of ultrasonic irradiation is necessary to degrade the more recalcitrant unsaturated daughter products.
Development and dissemination of Kanchan™ Arsenic Filter in rural Nepal
Authors: Ngai T.K.K. , Murcott S. , Shrestha R.R. , Dangol B. , Maharjan M.
Published: September 2006

In the rural Terai region of Nepal, many tubewell drinking water sources are microbially and/or arsenic contaminated and consequently, millions lack access to “safe” water. Those who drink contaminated water may suffer from preventable water-borne diseases such as diarrhoea, stunting, skin lesions, and cancer. To combat this problem, a team comprising researchers from Massachusetts Institute of Technology (MIT), together with two local partners, Environment & Public Health Organization (ENPHO), and Rural Water Supply and Sanitation Support Programme (RWSSSP), have developed an award-winning household water filter, the Kanchan™ Arsenic Filter (KAF), for simultaneous arsenic and pathogen removal. The KAF is constructed using locally available labour and materials and is optimised based on the local socio-economic conditions. The first part of this paper explains the technology development process and the technical details of this innovation. The second part of this paper describes the dissemination activities since 2004. This dissemination model not only built capacity in local people towards long-term, user-participatory safe water provision, but also made a contribution to the local economy. As of January 2006, over 25,000 people have gained access to safe water as a result of the implementation of the KAF.
The Canadian National Water and Wastewater Benchmarking Initiative. Using process to drive improvement: strategic management of water in urban areas
Authors: Main D. , Ng L. , North A.
Published: September 2006

Earth Tech has been successfully benchmarking Canadian municipal water, wastewater and stormwater utility operations since 1997. While the fundamental purpose of this project was metric benchmarking for the purpose of making performance comparisons to guide continuous improvement, the project is now serving as a dynamic platform to consider, examine, and implement a broad range of utility best practices that have resulted in superior performance where they have been implemented. The keys to success, however, were based more on a process that emphasizes communication, teamwork, and collaboration rather than the trend to push computerized data management systems to their fullest potential, and most importantly, in recognizing the importance of ‘hard work’. With these success factors now well understood and documented, it is feasible to benchmark almost any public infrastructure amongst agencies that are willing, regardless of their level of technological development. Finally, by sharing this methodology, the performance measure descriptions and detailed definitions, it is also feasible to make international comparisons in a simple and cost effective manner, thus opening the door to the broad exchange of international best practices.
An information disclosure technique for reducing citizens' concerns about tap water quality
Authors: Itoh S. , Hirayama N. , Kagawa K. , Shiro S. , Echigo S.
Published: September 2006

An information disclosure technique is proposed to reduce citizens' concerns about tap water quality. Psychological factors to reduce citizens' concerns were identified based on a cognitive appraisal model. Then, a questionnaire survey was conducted to statistically evaluate the effect of the types of information to the concern level of citizens about tap water quality. The results of the survey showed that the information that increases citizens' trust or controllability (i.e. citizens' perceptions that they can control the risk of tap water quality themselves) is effective in reducing their concern about tap water quality.
Variabilities in the cost equivalency of decentralized treatment units designed to address network-derived water quality degradation
Authors: Norton J.W. , Weber W.J.
Published: September 2006

Factors impacting the cost equivalency point for deploying strategically-located treatment units within a distributed optimal technology network (DOT-Net) to manage network-derived water quality degradation are defined and quantified. The cost equivalency point is essentially the ‘breakeven’ allowable cost for implementing DOT-Net strategy as an alternative to upgrading a central treatment facility to ‘pretreat’ water sufficiently to manage quality degradation within a potable water distribution network. For the purposes of the analysis presented, water quality is assumed to degrade linearly with time as it flows through the distribution network. Disinfection by-product (DBP) formation, selected as a representative water quality degradation parameter, was modeled to predict service population DBP exposure and resulting cost of centralized treatment plant upgrades to meet water quality goals. The equivalency point was determined by apportioning the anticipated cost for upgrading the centralized treatment facilities over the fraction of service connections receiving deficient quality water. Both concentration of DBP precursor material and service population size are found to have limited impact on the equivalency point of a distributed treatment unit. The advantages and disadvantages of various treatment methods available for in-network water treatment are outlined and the ancillary functional requirements of the distributed treatment unit are delineated.
Enhanced coagulation for improvement of water quality in full-scale water treatment
Authors: Yin J. , Liu Z.S. , Wang T.J. , Zhao K. , Cui Y.B. , Tan X.J.
Published: September 2006

Full-scale tests were conducted to evaluate the effectiveness of enhanced coagulation for improving water quality by increasing dosage and adding coagulant aid. As a result, enhanced coagulation by increasing dosage of PAC or adding activated silicate can increase water supply quality of old processes. But it cannot be taken for granted that single changing dosage or adding coagulant aid is a long-term technology for improving water quality, due to cost and other multi-barrier approaches.
Ozone and UV – a tool for multi-barrier concepts in water treatment
Authors: Ried A. , Mielcke J.
Published: September 2006

The use of ozone and/or UV for water treatment processes is often a combination of an ozone and/or UV-step with additional treatment steps, e.g. biological treatment, flocculation, filtration and activated carbon. Therefore, it is necessary to develop an optimized combination of these different steps. This article will demonstrate the advantages presenting two examples for drinking water treatment and two examples for municipal wastewater treatment.
Characterization of fouled membranes from a membrane enhanced biological phosphorus removal system
Authors: Geng Z. , Hall E.R.
Published: September 2006

Characterization of fouled membranes is the first step towards a good understanding of membrane fouling nature and thus formulating effective engineering measures for fouling prevention and control. In this study, fouled membrane fibres collected from a pilot scale membrane enhanced biological phosphorus removal (MEBPR) process were systematically examined. Several analytical tools, including scanning electron microscopy (SEM), conventional optical microscopy (COM), energy dispersive X-ray (EDX) microanalysis, matrix assisted laser desorption/ionization – mass spectrometry (MALDI-MS) analysis, and conventional chemical analysis techniques were used. The results indicated that membrane fouling in the MEBPR process was mainly of an organic nature, and most extractable foulants were carbohydrates and humic or humic-like substances. Unlike in other wastewater treatment membrane bioreactors, microbial growth on fouled membranes was not substantial, probably due to the vigorous aeration applied and the strong hydrodynamic conditions within the membrane pore structure. After a period of sludge filtration, membrane surfaces became more hydrophobic and the resultant hydrophobic interactions between the fouled membranes and mixed liquor constituents might have accelerated the fouling process.
Is the risk of illness through consuming vegetables irrigated with reclaimed wastewater different for different population groups?
Authors: Hamilton A.J. , Stagnitti F.S. , Premier R. , Boland A.-M.
Published: September 2006

The use of reclaimed wastewater for irrigation of horticultural crops is commonplace in many parts of the world and is likely to increase. Concerns about risks to human health arising from such practice, especially with respect to infection with microbial pathogens, are common. Several factors need to be considered when attempting to quantify the risk posed to a population, such as the concentration of pathogens in the source water, water treatment efficiency, the volume of water coming into contact with the crop, and the die-off rate of pathogens in the environment. Another factor, which has received relatively less attention, is the amount of food consumed. Plainly, higher consumption rates place one at greater risk of becoming infected. The amount of vegetables consumed is known to vary among ethic groups. We use Quantitative Microbial Risk Assessment Modelling (QMRA) to see if certain ethnic groups are exposed to higher risks by virtue of their consumption behaviour. The results suggest that despite the disparities in consumption rates by different ethnic groups they generally all faced comparable levels of risks. We conclude by suggesting that QMRA should be used to assess the relative levels of risk faced by groups based on divisions other than ethnicity, such as those with compromised immune systems.
Temperature and conductivity as control parameters for pollution-based real-time control
Authors: Schilperoort R.P.S. , Gruber G. , Flamink C.M.L. , Clemens F.H.L.R. , van der Graaf J.H.J.M.
Published: September 2006

Most sewer system performance indicators are not easily measurable online at high frequencies in wastewater systems, which hampers real-time control with those parameters. Instead of using a constituent of wastewater, an alternative could be to use characteristics of wastewater that are relatively easily measurable in sewer systems and could serve as indicator parameters for the dilution process of wastewater. This paper focuses on the possibility to use the parameters of temperature and conductivity. It shows a good relation of temperature and conductivity with the dilution of DWF (dry weather flow) during WWF (wet weather flow) a monitoring station in Graz, Austria, as an example. The simultaneous monitoring of both parameters leads to valuable back-up information in case one parameter (temperature) shows no reaction to a storm event. However, for various reasons, anomalies occur in the typical behaviour of both parameters. The frequency and extent of these anomalies will determine the usefulness of the proposed parameters in a system for pollution-based real-time control. Both the normal behaviour and the anomalies will be studied further by means of trend and correlation analyses of data to be obtained from a monitoring network for the parameters of interest that is currently being set up in the Netherlands.
Evaluation of nitrate removal by continuous culturing of an aerobic denitrifying bacterium, Paracoccus pantotrophus
Authors: Hasegawa-Kurisu K. , Otani Y. , Hanaki K.
Published: September 2006

Nitrate removal under aerobic conditions was investigated using pure cultures of Paracoccus pantotrophus, which is a well-known aerobic-denitrifying (AD) bacterium. When a high concentration of cultures with a high carbon/nitrogen (C/N) ratio was preserved at the beginning of batch experiments, subsequently added nitrate was completely removed. When continuous culturing was perpetuated, a high nitrate removal rate (66.5%) was observed on day 4 post-culture, although gradual decreases in AD ability with time were observed. The attenuation in AD ability was probably caused by carbon limitation, because when carbon concentration of inflow water was doubled, nitrate removal efficiency improved from 18.1% to 59.6%. Bacterial community analysis using the polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) method showed that P. pantotrophus disappeared in the suspended medium on day 8 post-culture, whereas other bacterial communities dominated by Acidovorax sp. appeared. Interestingly, this replaced bacterial community also showed AD ability. As P. pantotrophus was detected as attached colonies around the membrane and bottom of the reactor, this bacterium can therefore be introduced in a fixed form for treatment of wastewater containing nitrate with a high C/N ratio.
Aeration control for simultaneous nitrification-denitrification in a biological aerated filter using internal model approach
Authors: Lemoine C. , Payraudeau M. , Meinhold J.
Published: September 2006

Experience has shown that simultaneous nitrification/denitrification in a biological aerated filter is possible. However these systems react very sensitively to the aeration control strategies applied. Poorly adapted control strategies induce a strong decrease in treatment efficiency. A new control strategy for simultaneous N/DN is developed. The strategy proposed makes use of ammonia measurements and the inlet and outlet: a Feedback/Feedforward block. Passing by a calculation of the load to be eliminated, an estimation of the air flow velocity to be applied is carried out dynamically. A retroactive loop corrects this prediction in order to reach exactly the desired set point. This control approach has been implemented and tested at pilot plant scale for a period of 18 months. The pilot plant consists of two coupled BAF cells, reflecting closely industrial scale situations. Comparative studies reveal clearly the improved performance of the developed FF/FB control strategy compared to classical controllers. The benefits include 5% increase in nitrogen removal performance and a reduction of 15 to 20% in air requirement, offering a rapid return of investment costs.
Utilization of dried sludge for making ceramsite
Authors: Xu G.R. , Zou J.L. , Dai Y.
Published: September 2006

Dried sludge as additive for making ceramsite is a new effective approach for disposal of sludge. In this study sewage sludge, water glass and clay were chosen as the components, the optimal ratio of the components and the most appropriate conditions were obtained. The functions of primary components in the sintering process, porosity formation mechanism and solid phase reaction also have been discussed. The optimized process parameters were shown as follows: the ratio of dried sludge /clay (wt%) was 33%, ratio of adherent /clay (wt%) was 15%, sintering temperature was 1000 °C, sintering time was 10 min. Bulk density was 582 kg m−3, particle density was 1,033 kg m−3, water absorption was 9.5%, porosity was 43.7%. SEM, EDS, XRD and XRF analyses were also carried out. The results indicate that dried sludge as raw material is a good way for making ceramsite. Biological Aerated Filters (BAFs) with filter media of Guangzhou ceramsite, Jiangxi ceramsite, activated carbon and ceramsite (obtained in test) were selected to treat municipal wastewater. The average removal efficiencies of ceramsite (obtained in test) for turbidity, COD, SCOD and NH3-N were about 96.4%, 76.2%, 59.6% and 82.3% respectively and were higher than those of other ceramsites.
Resource recovery from excess sludge by subcritical water combined with magnesium ammonium phosphate process
Authors: Arakane M. , Imai T. , Murakami S. , Takeuchi M. , Ukita M. , Sekine M. , Higuchi T.
Published: September 2006

The amount of excess sludge produced in municipal wastewater treatment plants in Japan is increasing every year as the urban population increases. Phosphorus in excess sludge could be a potential phosphorus resource since at present, phosphate rock is being exhausted all over the world. Every year, Japan imports large quantities of phosphorus from abroad but much is discharged as excess sludge. Therefore, the solubilization process, one method of recovering phosphorus from sludge, could be a promising solution. In this study, a subcritical water process, a new technology that solubilizes sludge under subcritical conditions, was applied before the phosphorus in sludge was recovered with the magnesium ammonium phosphate (MAP) process. As a result, the solubilization rate of excess sludge achieved approximately 80% and about 94–97% of the phosphorus could be recovered.
Breakdown of air pockets in downwardly inclined sewerage pressure mains
Authors: Lubbers C.L. , Clemens F.H.L.R.
Published: September 2006

In the Netherlands, wastewater is collected in municipal areas and transported to centralised WWTPs by an extensive system of pressure mains. Over the last decades these pressure mains did not receive much attention in terms of monitoring of performance or maintenance. A recent inventory showed that half of the pressure mains show an increased pressure loss for no directly obvious reason. One of the many causes that account for the reduction of the flow capacity is the occurrence of free gas in the pipeline. During dry weather periods with low flow velocities, gas may accumulate at high points in the system. Once the velocity increases during storm weather flow, the air pockets may be broken down and transported to the end of the system. A research study is started focussing on the description of the gas-water phenomena in wastewater pressure mains with respect to transportation of gas. An experimental facility is constructed for the study of multi-phase flow. This paper describes the preliminary results of experiments on breakdown rates of gas pockets as a function of inclination angle and water flow rate. The results show an increasing breakdown rate with increasing inclination angle.
Effects of filtration temperature, humic acid level and alum dose on cryptosporidium sized particle breakthrough
Authors: Xu G.R. , Fitzpatrick C.S.B. , Deng L.Y.
Published: September 2006

Recent Cryptosporidium outbreaks have highlighted concerns about filter efficiency and especially particle breakthrough. Understanding the causes of breakthrough is essential, as the parasite cannot be destroyed by conventional disinfection with chlorine. Particle breakthrough depends on many factors. This research aims to investigate the influence of temperature, humic acid (HA) level and chemical dosing on particle breakthrough in filtration. A series of temperatures were set at 5 °C, 15 °C and 25 °C; humic acid level was 5 mg L−1. Each was combined with a series of Al doses. A laser particle counter was used to assess the particle breakthrough online. Turbidity, ζ potential, and UV254 absorption were measured before and after filtration. The results showed that particle breakthrough was influenced significantly by temperature, humic acid and dosing. Particle breakthrough occurred earlier at lower temperature, while at higher temperature it was reduced at the same coagulant dose. With coagulants, even at low dose, particle breakthrough was significantly reduced. With HA 5 mg L−1, particle breakthrough was earlier and the amount was much larger than without HA even at high temperature. There was an optimal dose in filtration and it was well correlated with ζ potential.
Trends in instrumentation, control and automation and the consequences on urban water systems
Authors: Häck M. , Wiese J.
Published: September 2006

In recent years more and more on-line sensors have been used on different structures of urban water systems (UWS, i.e. wastewater treatment plants (WWTP), waterworks (WW), sewer systems). This development is influenced and driven by numerous trends, which will be discussed in this paper. For a better understanding, the discussion is illustrated with a factual example. The new possibilities of on-line measurement and automation technologies will also change the way as UWS will be planned, built and operated.
Automation model of sewerage rehabilitation planning
Authors: Yang M.D. , Su T.C.
Published: September 2006

The major steps of sewerage rehabilitation include inspection of sewerage, assessment of structural conditions, computation of structural condition grades, and determination of rehabilitation methods and materials. Conventionally, sewerage rehabilitation planning relies on experts with professional background that is tedious and time-consuming. This paper proposes an automation model of planning optimal sewerage rehabilitation strategies for the sewer system by integrating image process, clustering technology, optimization, and visualization display. Firstly, image processing techniques, such as wavelet transformation and co-occurrence features extraction, were employed to extract various characteristics of structural failures from CCTV inspection images. Secondly, a classification neural network was established to automatically interpret the structural conditions by comparing the extracted features with the typical failures in a databank. Then, to achieve optimal rehabilitation efficiency, a genetic algorithm was used to determine appropriate rehabilitation methods and substitution materials for the pipe sections with a risk of mal-function and even collapse. Finally, the result from the automation model can be visualized in a geographic information system in which essential information of the sewer system and sewerage rehabilitation plans are graphically displayed. For demonstration, the automation model of optimal sewerage rehabilitation planning was applied to a sewer system in east Taichung, Chinese Taiwan.