bluuebunny/crossref_metadata_2025 huggingface dataset:
The application of economic-engineering optimisation for water management in Ensenada, Baja California, Mexico
Authors: Medellín-Azuara J. , Mendoza-Espinosa L.G. , Lund J.R. , Ramírez-Acosta R.J.
Published: January 2007

Mathematical optimisation is used to integrate and economically evaluate wastewater reuse, desalination and other water management options for water supply in Ensenada, Baja California Mexico with future levels of population and water demand. The optimisation model (CALVIN) is used to explore and integrate water management alternatives such as water markets, reuse and seawater desalination, within physical capacity constraints and the region's water availability, minimising the sum of economic costs of water scarcity and operating costs within a region. The modelling approach integrates economic inputs from agricultural and urban water demand models with infrastructure and hydrological information, to identify an economically optimal water allocation between water users in Ensenada. Estimates of agricultural and urban economic water demands for year 2020 were used. The optimisation results indicate that wastewater reclamation and reuse for the city of Ensenada is the most economically promising alternative option to meet future water needs and make water imports less attractive. Seawater desalination and other options are not economically viable alone, but may have some utility if combined with other options for the Ensenada region.
Spatial and temporal pollutant budget analyses toward the total maximum daily loads management for the Yeongsan watershed in Korea
Authors: Ki S.J. , Lee Y.G. , Kim S.-W. , Lee Y.-J. , Kim J.H.
Published: January 2007

This paper delivers two issues: water quality in the Yeongsan (YS) watershed which is one of the major watersheds in Korea and new watershed management plans with respect to the total maximum daily loads (TMDL) management. Field studies were conducted to estimate the pollutant loads according to the spatial and temporal distribution based on the biochemical oxygen demand (BOD) concentration and the volumetric flow rate (VFR) data from YS watershed. The results of both spatial and temporal analyses show the main pollutant source was originated from the city of Gwangju and the pollutant load from the city to YS watershed was the most out of five cities during this study period. Concerning YS reservoir located downstream of YS watershed, it also shows the worst water quality in the entire watershed during the study period. These results collectively demonstrate that the city of Gwangju is a main region which generates numerous point and non-point pollutant sources and eventually the pollutants are accumulated in YS reservoir. Based on the results, we suggest two different management plans for YS watershed. One is the flow-control approach that is to increase the amount of dam discharge in order to guarantee the river management flow for the midstream region. The other is the mass-control approach that is to dredge the contaminated sediments in YS reservoir for removing pollutants chronically accumulated in the sediment. Simulations for the former and the latter provide the pollution mitigation rate in the watershed up to 6 and 8% for BOD5, respectively. The methodology proposed here for TMDL management can be applied to a wide range of watersheds in Korea.
Considerations on the issue of water reuse in eastern China plain brooky regions
Authors: Wei C. , Xingcan Z. , Tao L.
Published: January 2007

This paper summarises the characteristics of water systems in plain brooky regions of Jiangsu Province in eastern China, and discusses the water shortage issue resulting from water quality deterioration. It is emphasised that attention should be paid not only to the full treatment of wastewater and rainwater but also the proper disposal of treated wastewater which meets the national discharge standard GB18918-2002 but still contain significant amount of pollutants if compared with the national surface water quality standard GB3838-2002. To the plain brooky regions of Jiangsu Province, the discharged pollutant loads still significantly exceed the environmental capacity of the receiving waters even if all treated wastewater meet the first grade B limits of GB18918-2002, and the water pollution problem still cannot be really eliminated. Therefore, the disposal and utilisation of the treated wastewater need to be taken into consideration. Thus, this paper presents some considerations on the disposal of treated wastewater and management of urban rainwater, mainly concerning water reclamation and reuse, construction of ecological purification systems, strategy changes of wastewater and rainwater management, and the key technology selections.
Reuse of a dyehouse effluent after being treated with the combined catalytic wet peroxide oxidation process and the aerated constructed wetland
Authors: Lee D.-K. , Kim S.-C. , Yoon J.-H.
Published: January 2007

A catalytic wet peroxide oxidation process was combined with the aerated constructed wetland in order to treat the raw dyehouse wastewater to in acceptable level for reuse as washing process water. More than 90% of BOD and CODs could be removed with the wet peroxide oxidation reactor and the remaining pollutants in the treated water were transformed into biodegradable ones which could have been successfully treated at the following aerated constructed wetland. The highest values of BOD5, CODMn, CODCr, SS and T-N in the treated water were 1.6, 1.8, 2.1, 0.5 and 12.8 mg/L, respectively. These values were low enough for the treated water to be reused at the washing process.
Performance of slow rate systems for treatment of domestic wastewater
Authors: Tzanakakis V.E. , Paranychianakis N.V. , Angelakis A.N.
Published: January 2007

The performance of slow rate (SR) systems in terms of treatment efficiency, environmental and health risks, and land sustainability was investigated over a three-year period in a rural community close to Iraklio, Greece. Four plant species (Acacia cyanophylla, Eucalyptus camandulensis, Populus nigra and Arundo donax) were used in order to investigate the role of vegetation in the treatment of wastewater and in biomass production. Wastewater effluent was pre-treated in a septic tank before its application to land. Applied hydraulic loading rates were based on crop water requirements which were determined separately for each plant species. The evaluation of treatment performance was accomplished by measuring COD, TKN, NH3-N, NO3-N, total and reactive P, TC and FC in soil solution samples taken at different depths (15, 30 and 60 cm). SR systems showed great potential for COD, TKN and NH4-N removal which reached 89, 90 and 94%, respectively at a depth of 15 cm. An outstanding removal was also observed for TC and FC which reached 99.99%. The concentration of both P and NO3-N in soil solution increased with the passage of time, but it was lower in winter. Despite the differences in the application rates among the SR systems planted with different plant species, the treatment efficiency was not affected. Moreover, increasing the soil depth from 15 to 60 cm had no effect on the treatment efficiency of the SR systems.
Relationship between the electric conductivity and phosphorus concentration variations in an enhanced biological nutrient removal process
Authors: Kim Kwang-Soo , Yoo Ji-Seon , Kim Sungyoun , Lee Hee Ja , Ahn Kwang-Ho , Kim In S.
Published: January 2007

Phosphorus release and uptake in a sequencing batch reactor were monitored by the simple on-line measurements of electric conductivity (EC) and oxidation-reduction potential (ORP), and the result was verified by the measurement of phosphate concentration changes. The influence of nitrate ion presence on the phosphorus removal was evaluated by a jar test operated in the cyclic anaerobic (anoxic)–aerobic condition. The relationships of EC, ORP and metal species with phosphorus concentrations were investigated. Under strict anaerobic conditions, EC showed positive correlation with phosphorus concentrations, but it became negligible under anoxic conditions with nitrate present. Strong inverse correlation was found between ORP values and phosphorus concentration. The increase and decrease of magnesium and potassium ions took place in accordance with phosphorus release and uptake, and the relationship between the metal species and phosphorus changes was clearer in the anaerobic condition than anoxic condition.
A Performance‐Based Framework for Demonstrating Appropriate Use of an Alternate Method for Wastewater Compliance Monitoring
Authors: Diamond Jerome M. , Eaton Andrew D. , Annis Clifford , Vitale Rock , Brass Herbert J.
Published: January 2007

The choice of wastewater compliance methods used in the United States has been largely prescribed; however, in some cases, this has led to data of unknown or poor quality. This problem is further compounded by the relatively slow regulatory approval process to incorporate discharge‐specific method modifications or flexibility to using alternate, potentially better technologies. In this study, a framework is presented, using a performance‐based‐system approach, which a discharger could use to verify proper use of an alternate or modified method. An example, using two chemical oxygen demand methods (a currently approved method and an alternate method that does not generate hazardous waste) demonstrates that the protocol is simple to use, yet scientifically defensible and effective and that this approach should be readily understandable to both regulators and the regulated community. Our results also suggest that the reference method approach, without associated measurement quality objectives, may yield a false sense of competency with an alternate method.
Cloth Media Filtration and Membrane Microfiltration: Serial Operation
Authors: Tooker Nicholas Brewster , Darby Jeannie L.
Published: January 2007

A combined system comprised of a cloth media filter and a membrane microfilter operated in series was used to treat secondary effluent. The study objective was to investigate the effect of premembrane filtration on the maximum sustainable membrane flux, transmembrane pressure, and effluent quality. The maximum sustainable time‐averaged flux under predefined operating conditions (i.e., 15‐minute process cycle, 24‐hour chemical cleaning cycle, and 30‐day intensive cleaning cycle) was 127 L/m 2·h. Typical flux rates for secondary effluent ranged from 40 to 55 L/m 2·h. Effluent water quality from the combined system was high and independent of membrane flux and influent quality. Average membrane effluent water quality values were 0.04 NTU for turbidity and 1.4 mg/L for 5‐day biochemical oxygen demand. Neither total nor fecal coliforms were detected. Based on the results presented herein, prefiltration would provide an annualized cost savings of approximately 12% over microfiltration alone for a 3.8 × 10 3 m 3/d treatment facility.
Statistical Evaluation of the Influence of Flow Conditions and Sampling Techniques on Water Quality Data
Authors: Daas Mutaz , Srivastava Rajiv , Conklin Walter
Published: January 2007

The purpose of this study is to statistically evaluate the influence of various sampling methodologies and flow conditions on the quality and comparability of total phosphorus concentration data collected over the course of 27 months at the South Florida Water Management District (SFWMD) S‐65E structure. The data was obtained from the following sampling methodologies: U.S. Geological Survey (USGS) (Reston, Virginia) equal width increment spatially composite grab samples, USGS replicate samples, SFWMD grab samples, and SFWMD autosampler samples. Both significant and insignificant differences were reported from these comparisons. Parametric and nonparametric standard statistical tests for significance were carried out to evaluate the differences between the data. To avoid invalid conclusions of insignificant differences, we conducted tests for equivalence of the means and variances. The results from the data analysis revealed that both flow conditions and sampling methodology affected the water quality data.
Effects of Development on Runoff and Pollutant Export
Authors: Line D.E. , White N.M.
Published: January 2007

Runoff from two similar drainage areas in the Piedmont physiographic region of North Carolina was monitored simultaneously for 5.6 years. One of the drainage areas was developed as part of a large residential subdivision, while the other remained in woods and agricultural fields. Runoff volume was 68% greater for the developed compared with the undeveloped area, and baseflow as a percentage of overall discharge was approximately 0% compared with 25% for the undeveloped area. Overall annual export of sediment was 95% greater for the developed area, while export of nitrogen and phosphorus forms was 66 to 88% greater for the developed area. These results document the significant increases in runoff, sediment, and nutrient export associated with residential development.
Influence of a Three‐Phase Separator Configuration on the Performance of an Upflow Anaerobic Sludge Bed Reactor Treating Wastewater from a Fruit‐Canning Factory
Authors: Wongnoi Rachbordin , Songkasiri Warinthorn , Phalakornkule Chantaraporn
Published: January 2007

The objective of this study was to investigate the influence of a three‐phase separator configuration on the performance of an upflow anaerobic sludge bed (USAB) treating wastewater from a fruit canning factory. The performances of two 30‐L UASB reactors—one with a modified three‐phase separator giving a spiral flow pattern and the other with a conventional configuration—were investigated in parallel. Wastewater, with a chemical oxygen demand (COD) concentration between 2000 and 7000 mg/L, was obtained from a fruit‐canning factory. Based on the effluent data of the first 100 operation days, the UASB with the three‐phase separator giving spiral flow patterns yielded up to 25% lower biomass washout. It also showed better efficiencies in treating wastewater—up to 60% lower effluent COD, up to 20% higher COD percent removal, and up to 29% higher biogas production. This work presents evidence of an improvement on the conventional physical design of a UASB.
Human Pharmaceuticals, Antioxidants, and Plasticizers in Wastewater Treatment Plant and Water Reclamation Plant Effluents
Authors: Soliman Mary A. , Pedersen Joel A. , Park Heesu , Castaneda‐Jimenez Angelica , Stenstrom Michael K. , Suffet I. H. (Mel)
Published: January 2007

The primary objective of this study was to determine the presence of unregulated organic chemicals in reclaimed water using complementary targeted and broad spectrum approaches. Eleven of 12 targeted human pharmaceuticals, antioxidants, and plasticizers, and 27 tentatively identified non‐target organic chemicals, were present in secondary effluent entering tertiary treatment trains at a wastewater treatment plant and two water reclamation facilities. The removal of these compounds by three different tertiary treatment trains was investigated: coagulant‐assisted granular media filtration (California Title‐22 water, 22 CCR §§60301‐60357; Barclay [2006]), lime clarification/reverse osmosis (lime/RO), and microfiltration‐reverse osmosis (MF/RO). Carbamazepine, clofibric acid, gemfibrozil, ibuprofen, p‐toluenesulfonamide, caffeine, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), and N‐butyl benzenesulfonamide (N‐BBSA) were present at low to high nanogram‐per‐liter levels in Title 22 water. The lime/RO product waters contained lower concentrations of clofibric acid, ibuprofen, caffeine, BHA, and N‐BBSA (<10 to 71 ng/L) than their Title 22 counterparts. The MF/RO treatment reduced concentrations to levels below their detection limits, although BHT was present in MF/RO product water from one facility. The presence of the target analytes in two surface waters used as raw drinking water sources and a recharged groundwater was also examined. Surface waters used as raw drinking water sources contained caffeine, BHA, BHT, and N‐BBSA, while recharged groundwater contained BHT, BHA, and N‐BBSA. Nontarget compounds in recharged groundwater appeared to be attenuated with increased residence time in the aquifer.
Access to and Satisfaction with Care Comparing Patients with and without Serious Mental Illness
Authors: Kilbourne Amy M. , McCarthy John F. , Post Edward P. , Welsh Deborah , Pincus Harold Alan , Bauer Mark S. , Blow Frederic C.
Published: January 2007

Objectives:

We compared perceived access to and satisfaction with health care between patients diagnosed with serious mental illness (SMI: schizophrenia or bipolar disorder) and among those with no SMI diagnosis.

Method:

We conducted a national, cross-sectional study of VA patients in Fiscal Year (FY) 1999 (N=7,187) who completed the VA's Large Health Survey of Veteran Enrollees (LHSV) section on access and satisfaction and either received a diagnosis of schizophrenia or bipolar disorder, or did not and were randomly selected from the general non-SMI VA patient population (non-SMI group). We compared the probability of perceived poor access and dissatisfaction using multivariable logistic regression adjusting for patient covariates.

Results:

Compared to non-SMI patients, patients diagnosed with bipolar disorder were more likely to report difficulty in receiving care they needed (adjusted OR =1.36, p < .05) or seeing a specialist (adjusted OR=1.44, p < .001). Patients diagnosed with schizophrenia were more likely to report dissatisfaction, including thoroughness by their provider (adjusted OR=1.37, p < .001) and the provider's explanation of problems (adjusted OR=1.54, p < .001) compared to non-SMI patients.

Conclusions:

Patients diagnosed with bipolar disorder reported greater problems with access to health care, while those diagnosed with schizophrenia were less satisfied with the process of care.
Goal Clarity and Financial Planning Activities as Determinants of Retirement Savings Contributions
Authors: Stawski Robert S. , Hershey Douglas A. , Jacobs-Lawson Joy M.
Published: January 2007

Retirement counselors, financial service professionals, and retirement intervention specialists routinely emphasize the importance of developing clear goals for the future; however, few empirical studies have focused on the benefits of retirement goal setting. In the present study, the extent to which goal clarity and financial planning activities predict retirement savings practices was examined among 100 working adults. Path analysis techniques were used to test two competing models, both of which were designed to predict savings contributions. Findings provide support for the model in which retirement goal clarity is a significant predictor of planning practices, and planning, in turn, predicts savings tendencies. Two demographic variables—income and age—were also revealed to be important elements of the model, with income accounting for roughly half of the explained variance in savings contributions. The results of this study have implications for the development of age-based models of planning, as well as implications for retirement counselors and financial planners who advise workers on long-term saving strategies.
Correlates of Quality of Life in Primary Care Patients with Hypertension
Authors: Ayalon Liat , Gross Revital , Tabenkin Hava , Porath Avi , Heymann Anthony , Porter Boaz
Published: January 2007

Background:

Hypertension has been associated with lower levels of quality of life (QoL). However, the specific correlates of lower QoL in this patient population have remained largely unclear.

Methods:

A cross-sectional design of 1,125 primary care patients with hypertension. We evaluated demographics, health status, subjective health and mental health, health behaviors, health beliefs, knowledge of hypertension treatment, satisfaction with medical care, and quality of medical care as potential predictors of QoL and perceived QoL in the hypothetical absence of hypertension.

Results:

Worse financial status, poorer blood pressure control, worse subjective health, mental distress, lack of hypertension diet, and irregular hypertension care were all associated with worse QoL. Worse financial status, poorer blood pressure control, higher body mass index, mental distress, and following a hypertension diet were associated with better QoL in the hypothetical absence of hypertension.

Conclusions:

In addition to taking into consideration well known determinants of QoL, such as financial status, health status, and mental health, physicians need to be aware of the potential tradeoff between following medical recommendations that advocate for a strict diet and the impact these have on patients' QoL. Physicians also need to be aware of the effect of imparting information regarding imbalanced blood pressure on perceived QoL.
Diversion Dam Cave (10-AA-99): A Paleoindian Site near Boise, Idaho
Authors: Rogers Alexander K. , Yohe Robert M.
Published: January 2007

In this article we describe the results of excavation at the Diversion Dam Cave (10-AA-99) near Boise, Idaho, sponsored by the Bureau of Reclamation. Although the site has been heavily impacted over the years by illegal digging and urban encroachment, the data from these excavations confirmed that some deposits are intact. Radiocarbon data suggest a Paleoindian occupation, prior to 9220 ± 100 RCYBP and as far back as approximately 12,000 RCYBP. No artifacts diagnostic of a specific cultural group were recovered, but the hearth features, hand polish on rocks, and river cobbles with pecking damage all point to human occupation. Faunal analysis suggests that small and medium mammals and fish were exploited, while botanical data suggest the use of both local and more distant resources as fuel. Although the cultural deposits were sparse, radiocarbon dates suggest occupation during the Paleoarchaic Period, a time frame with few examples in Idaho.
The Effects of Erosion on Archaeological Sites along the Upper Oahe Reservoir, South Dakota
Authors: Speakman Robert J. , Johnson Craig M.
Published: January 2007

Shoreline erosion of archaeological sites along Lake Oahe, North and South Dakota since the late 1960s has resulted in substantial destruction to many significant and potentially National Register eligible archaeological sites. Using aerial photographs dating to the late-1930s, site maps, and recent aerial photographs, we document the effects of erosion at three major village sites located in the Northern Cannonball region of South Dakota. As a result of a prolonged drought, erosion of archaeological sites has been minimal since the late 1990s. When the current drought cycle ends, erosion will likely resume at pre-drought rates of 3 to 5 meters per year.
Occult PTSD with Panic Attacks in a Patient Post-Tia: Case Report
Authors: Chardavoyne John , Frechette Vincent E.
Published: January 2007

Affective disorders are common sequelae of cerebrovascular events. A myriad of evidence demonstrates that clinically significant depression can often follow a stroke. However, less is known about the extent to which anxiety disorders present after these experiences, and in particular, posttraumatic stress disorder (PTSD) with panic attacks. To our knowledge, the association between transient ischemic attacks (TIAs) and PTSD with panic attacks has not been described in the literature. Here we describe a patient with depression and PTSD with panic attacks following a transient ischemic attack. Many non-psychiatric physicians learn about post-stroke depression so they are equipped to screen for it. However, to many physicians, PTSD with panic attacks usually conjures the image of an individual who experienced either trauma or rape. Therefore, it is important to increase the awareness of such complications after TIAs. Increased awareness of these TIA sequelae has important implications for detection by non-psychiatric healthcare providers. Furthermore, prompt recognition and treatment has important implications for patient quality of life.
A Cohort Study to Assess the Impact of Depression on Patients with Kidney Disease
Authors: Zimmermann Paulo Roberto , Camey Suzi Alves , De Jesus Mari Jair
Published: January 2007

Aims:

This study assessed the impact of depression on mortality and quality of life of patients with kidney disease.

Material:

This study was conducted at Hospital São Lucas of Pontificia Universidade Católica of Rio Grande do Sul, Porto Alegre, Brazil, with a cohort of 125 patients seen from 1996 to 2004 (mean follow-up=77.6 months). Patients undergoing renal replacement therapy were asked to fill in the Beck Depression Inventory (BDI). At the completion of follow-up, 72 patients were alive, and 56 answered the BDI and the Medical Outcome Study Short Form General Health Survey (SF-36) to assess quality of life. Main outcome measures were mortality and quality of life.

Results:

Initial analysis showed that mortality was associated with age, treatment modality—continuous ambulatory peritoneal dialysis (CAPD) or hemodialysis (hd)—and depression. When controlling for age, gender, depression, and treatment modality in a multiple regression analysis, transplantation (tx), gender and age was associated with lower mortality. However, levels of depression at the end of follow-up were strongly associated with quality of life.

Conclusions:

Depression was not associated with mortality of patients with kidney disease when controlling for gender, age, and treatment modality. Transplantation was the main factor associated with lower mortality. Depression was, however, a strong predictor of quality of life. Number of depressive symptoms was directly associated with lower quality of life in most of the items of the SF-36.
Institutional and Individual Autonomy: Investigating Predictors of Attitudes toward Institutional Care in China
Authors: Guan Xinping , Zhan Heying Jenny , Liu Guangya
Published: January 2007

This study examines the institutional and attitudinal changes in elder care homes in Tianjin, China. Based on a survey conducted in 2001 with 61 elder home managers and 265 elder residents, this study examines 1) factors that influence elder home managers' views about elder home development and 2) elders' evaluation of elder home quality and their levels of willingness to stay in such homes. Findings show that elder home managers view their autonomy in financing and administration as a very important factor for future development of an elder home industry. Elders' overall evaluation of elder home quality was high. Elders' willingness to stay in elder homes was related to two factors: their living arrangements prior to elder home placement and their assessment of the cost involved for such care. This suggests that the limited level of autonomy in private elder home administration and financing is hindering the development of elder homes. As adult children become increasingly unavailable due to the one-child policy and geographic mobility, institutional care for aging parents is likely to become a major option for familial care in China. The government should grant greater autonomy to private elder homes in order to encourage elder home development.
Determinants of Computer Self-Efficacy—An Examination of Learning Motivations and Learning Environments
Authors: Hsu Wen-Kai K. , Huang Show-Hui S.
Published: January 2007

The purpose of this article is to discuss determinants of computer self-efficacy from the perspective of participant internal learning motivations and external learning environments. The former consisted of three motivations—interest, trend, and employment—while the latter comprised two environments—home and school. Through an intermediate variable—computer use—a causal model was constructed to analyze how the determinants affected participant computer self-efficacy. To validate the model, 235 vocational and technology college and university students were surveyed. The results indicated that computer use and interest motivation had significant direct effects on participant computer self-efficacy, as did school environment and trend motivations, but the latter was negative. The home environment and employment motivations had indirect effects on computer self-efficacy through computer use, as did the interest and trend motivations. Among the correlations of determinants, the home environment was significantly correlated with all of the learning motivations, but school environment was not. Demographic analysis indicated that most of the students were not satisfied with the learning environment of schools. The results could provide useful and practical information for educational administrators, computer instructors, and students.
A 6,000 Year Old Red Abalone Midden from Otter Point, San Miguel Island, California
Authors: Vellanoweth René L. , Reynolds Gnesa , Rick Torben C. , Erlandson Jon M.
Published: January 2007

For decades, researchers have been interested in archaeological sites on California's Channel Islands that contain large concentrations of red abalone ( Haliotis rufescens) shells. Known as red abalone middens and dated to between about 7500 and 3500 years ago, these sites have been used to understand broad subsistence patterns, provide chrono-stratigraphic control, and investigate past environmental changes in the region. Most detailed studies have focused on red abalone middens from Santa Cruz Island, with comparatively limited data from other islands. Analysis of a red abalone midden sample excavated from a large dune site on San Miguel Island illustrates the diversity of the red abalone site type and associated human behaviors. Rapid changes in the primary midden constituents, from California mussels ( Mytilus californianus) and sea mammals to red abalones, demonstrate the complexities of differentiating between the effects of environmental change, human food choices, and ecological changes associated with human impacts on local environments.
The Accurate Diagnosis of Early-Onset Dementia
Authors: Mendez Mario F.
Published: January 2007

Early-onset dementia (EOD, <65 years at onset) is a relatively common and frequently misdiagnosed condition. One reason for misdiagnosis is that EOD has a more varied differential diagnosis than late-onset dementia (LOD). For example, Alzheimer's disease (AD), the preponderant LOD, makes up only about one-third of EODs; the rest are due to vascular dementias, frontotemporal lobar degenerations, traumatic head injury, alcohol-related dementia, and a great many other conditions. Another reason for misdiagnosis is that early-onset AD may have predominant cognitive deficits other than memory loss and a potential familial inheritance with spastic paraparesis, seizures, or myoclonus. A third reason is that EOD often presents with neuropsychiatric features out-of-proportion to any cognitive deficits. Despite these obstacles, it is important to accurately diagnose EODs, particularly because they differ in management and course. Clinicians can successfully diagnose most EODs with careful cognitive and family histories, mental status and neurological examinations, and neuroimaging.
Quality of Life and Associated Factors among Adults with Epilepsy in Nigeria
Authors: Mosaku Kolawole S. , Fatoye Femi O. , Komolafe Morenikeji , Lawal Musiliu , Ola Bola A.
Published: January 2007

Objective:

Epilepsy is a common condition worldwide and has been observed to affect quality of life (QOL). Though, much has been written on this subject among western populations, little research has been done in developing countries of Africa including Nigeria. The study aims to identify factors associated with quality of life among adult epilepsy patients in this environment.

Method:

Respondents were evaluated using the 10-item Quality of Life in Epilepsy Inventory (QOLIE-10), the 30-item General Health Questionnaire (GHQ-30), the modified Mini Mental State Examination (mMMSE), and the Hospital Anxiety and Depression Scale (HADS). Diagnosis of epilepsy was based on clinical and electroencephalographic findings.

Results:

The mean age of the 51 respondents was 27.7years ( SD = 9.7). Thirteen (25.5%) had an average of 2 seizure episodes in the month preceding the interview, while 37 (72.5%) have had the condition for more than 5 years. Factors that were significantly associated with overall quality of life included being female ( p < 0.05), seizure frequency ( p < 0.01), using more than 1 anti-epileptic drugs (AEDs) ( p < 0.01), GHQ-30 score ( p < 0.01), high anxiety score ( p < 0.001), and high depression score ( p < 0.01). Multiple regression analysis showed that depressive symptoms were the single most important factor explaining low QOL. Other factors were GHQ-30 score, seizure frequency, and being a woman.

Conclusion:

Controlling seizures and paying attention to the psychological needs of adult epileptics will have a positive effect on the QOL among Nigerian epileptics.
Experimental Evidence on the Effectiveness of Automated Essay Scoring in Teacher Education Cases
Authors: Riedel Eric , Dexter Sara L. , Scharber Cassandra , Doering Aaron
Published: January 2007

Research on computer-based writing evaluation has only recently focused on the potential for providing formative feedback rather than summative assessment. This study tests the impact of an automated essay scorer (AES) that provides formative feedback on essay drafts written as part of a series of online teacher education case studies. Seventy preservice teachers in four teacher education classes were assigned to complete two cases. Each student was randomly assigned to either a condition where the AES was available (experimental condition) or a condition where the AES was unavailable (control condition). Students in the experimental condition who opted to use the AES submitted more highly rated final, human-scored essays (in the second of two case studies) and conducted more relevant searches (in both of the two case studies) than students either in the control condition or in the experimental condition who chose not to use the scorer.
On quasi‐likelihood inference in generalized linear mixed models with two components of dispersion
Authors: Sutradhar Brajendra C. , Rao R. Prabhakar
Published: January 2007

The authors propose a quasi‐likelihood approach analogous to two‐way analysis of variance for the estimation of the parameters of generalized linear mixed models with two components of dispersion. They discuss both the asymptotic and small‐sample behaviour of their estimators, and illustrate their use with salamander mating data.
A fast distance‐based approach for determining the number of components in mixtures
Authors: Sahu Sujit K. , Cheng Russell C. H.
Published: January 2007

The authors propose a procedure for determining the unknown number of components in mixtures by generalizing a Bayesian testing method proposed by Mengersen & Robert (1996). The testing criterion they propose involves a Kullback‐Leibler distance, which may be weighted or not. They give explicit formulas for the weighted distance for a number of mixture distributions and propose a stepwise testing procedure to select the minimum number of components adequate for the data. Their procedure, which is implemented using the BUGS software, exploits a fast collapsing approach which accelerates the search for the minimum number of components by avoiding full refitting at each step. The performance of their method is compared, using both distances, to the Bayes factor approach.
Simple estimation of the mode of a multivariate density
Authors: Abraham Christophe , Biau Gérard , Cadre Benoît
Published: January 2007

The authors consider an estimate of the mode of a multivariate probability density using a kernel estimate drawn from a random sample. The estimate is defined by maximizing the kernel estimate over the set of sample values. The authors show that this estimate is strongly consistent and give an almost sure rate of convergence. This rate depends on the sharpness of the density near the true mode, which is measured by a peak index.
Exactly optimal sampling designs for processes with a product covariance structure
Authors: Mukherjee Bhramar
Published: January 2007

The author considers the problem of finding exactly optimal sampling designs for estimating a second‐order, centered random process on the basis of finitely many observations. The value of the process at an unsampled point is estimated by the best linear unbiased estimator. A weighted integrated mean squared error or the maximum mean squared error is used to measure the performance of the estimator. The author presents a set of necessary and sufficient conditions for a design to be exactly optimal for processes with a product covariance structure. Expansions of these conditions lead to conditions for asymptotic optimality.
Empirical likelihood confidence regions for comparison distributions and roc curves
Authors: Claeskens Gerda , Jing Bing‐Yi , Peng Liang , Zhou Wang
Published: January 2007

Abstract: The authors derive empirical likelihood confidence regions for the comparison distribution of two populations whose distributions are to be tested for equality using random samples. Another application they consider is to ROC curves, which are used to compare measurements of a diagnostic test from two populations. The authors investigate the smoothed empirical likelihood method for estimation in this context, and empirical likelihood based confidence intervals are obtained by means of the Wilks theorem. A bootstrap approach allows for the construction of confidence bands. The method is illustrated with data analysis and a simulation study.
Nonparametric estimation of renewal processes from count data
Authors: Guédon Yann , Cocozza‐Thivent Christiane
Published: January 2007

Abstract: The authors address the problem of estimating an inter‐event distribution on the basis of count data. They derive a nonparametric maximum likelihood estimate of the inter‐event distribution utilizing the EM algorithm both in the case of an ordinary renewal process and in the case of an equilibrium renewal process. In the latter case, the iterative estimation procedure follows the basic scheme proposed by Vardi for estimating an inter‐event distribution on the basis of time‐interval data; it combines the outputs of the E‐step corresponding to the inter‐event distribution and to the length‐biased distribution. The authors also investigate a penalized likelihood approach to provide the proposed estimation procedure with regularization capabilities. They evaluate the practical estimation procedure using simulated count data and apply it to real count data representing the elongation of coffee‐tree leafy axes.
Loss functions for estimation of extrema with an application to disease mapping
Authors: Wright Deanne L. , Stern Hal S. , Cressie Noel
Published: January 2007

It is often of interest to find the maximum or near maxima among a set of vector‐valued parameters in a statistical model; in the case of disease mapping, for example, these correspond to relative‐risk “hotspots” where public‐health intervention may be needed. The general problem is one of estimating nonlinear functions of the ensemble of relative risks, but biased estimates result if posterior means are simply substituted into these nonlinear functions. The authors obtain better estimates of extrema from a new, weighted ranks squared error loss function. The derivation of these Bayes estimators assumes a hidden‐Markov random‐field model for relative risks, and their behaviour is illustrated with real and simulated data.
Local influence for generalized linear mixed models
Authors: Zhu Hong‐Tu , Lee Sik‐Yum
Published: January 2007

The authors describe a method for assessing model inadequacy in maximum likelihood estimation of a generalized linear mixed model. They treat the latent random effects in the model as missing data and develop the influence analysis on the basis of a Q‐function which is associated with the conditional expectation of the complete‐data log‐likelihood function in the EM algorithm. They propose a procedure to detect influential observations in six model perturbation schemes. They also illustrate their methodology in a hypothetical situation and in two real cases.
Formation of 1D Poly(3,4‐ethylenedioxythiophene) Nanomaterials in Reverse Microemulsions and Their Application to Chemical Sensors
Authors: Yoon H. , Chang M. , Jang J.
Published: February 2007

1D poly(3,4‐ethylenedioxythiophene) (PEDOT) nanomaterials, including ellipsoidal nanoparticles, nanorods, and nanotubes, are fabricated via chemical oxidation polymerization in reverse (water‐in‐oil) microemulsions. The reverse cylindrical micelles are prepared with sodium bis(2‐ethylhexyl) sulfosuccinate (AOT) and aqueous FeCl3 solution in hexane. The morphology of the final products is determined by carefully tuning the degree of oxidation potential at the micelle surface. Notably, the fabrication of gram‐scale amounts of products is possible under optimized synthetic conditions, suggesting that this methodology is appropriate for the large‐scale production of the corresponding nanomaterials. The as‐prepared PEDOT nanomaterials are applied to the precise detection of alcohol vapors. The chemical sensors based on the PEDOT nanomaterials present excellent reversibility and reproducibility in response.
Surface‐Modified High‐k Oxide Gate Dielectrics for Low‐Voltage High‐Performance Pentacene Thin‐Film Transistors
Authors: Kim C. S. , Jo S. J. , Lee S. W. , Kim W. J. , Baik H. K. , Lee S. J.
Published: January 2007

In this study, pentacene thin‐film transistors (TFTs) operating at low voltages with high mobilities and low leakage currents are successfully fabricated by the surface modification of the CeO2–SiO2 gate dielectrics. The surface of the gate dielectric plays a crucial role in determining the performance and electrical reliability of the pentacene TFTs. Nearly hysteresis‐free transistors are obtained by passivating the devices with appropriate polymeric dielectrics. After coating with poly(4‐vinylphenol) (PVP), the reduced roughness of the surface induces the formation of uniform and large pentacene grains; moreover, –OH groups on CeO2–SiO2 are terminated by C6H5, resulting in the formation of a more hydrophobic surface. Enhanced pentacene quality and reduced hysteresis is observed in current–voltage (I–V) measurements of the PVP‐coated pentacene TFTs. Since grain boundaries and –OH groups are believed to act as electron traps, an OH‐free and smooth gate dielectric leads to a low trap density at the interface between the pentacene and the gate dielectric. The realization of electrically stable devices that can be operated at low voltages makes the OTFTs excellent candidates for future flexible displays and electronics applications.
Salicylaldimine Ruthenium Alkylidene Complexes: Metathesis Catalysts Tuned for Protic Solvents
Authors: Binder Joseph B. , Guzei Ilia A. , Raines Ronald T.
Published: February 2007

Tuning the electronic and steric environment of olefin metathesis catalysts with specialized ligands can adapt them to broader applications, including metathesis in aqueous solvents. Bidentate salicylaldimine ligands are known to stabilize ruthenium alkylidene complexes, as well as allow ring‐closing metathesis in protic media. Here, we report the synthesis and characterization of exceptionally robust olefin metathesis catalysts bearing both bidentate salicylaldimine and N‐heterocyclic carbene ligands, including a trimethylammonium‐functionalized complex adapted for polar solvents. NMR spectroscopy and X‐ray crystallographic analysis confirm the structures of the complexes. Although the N‐heterocyclic carbene–salicylaldimine ligand combination limits the activity of these catalysts in non‐polar solvents, this pairing enables efficient ring‐closing metathesis of both dienes and enynes in methanol and methanol/water mixtures under air.
Enantioselective Hydrogenation of N‐Acetyldehydroamino Acids over Supported Palladium Catalysts
Authors: Szöllősi György , Szabó Emese , Bartók Mihály
Published: February 2007

The enantioselective hydrogenation of two N‐acetyldehydroamino acids over Cinchona alkaloid‐modified, supported palladium catalysts has been studied. Moderate enantioselectivities, up to 36 %, were obtained in the hydrogenation of 2‐acetamidocinnamic acid over cinchonidine‐modified Pd/TiO2 under low hydrogen pressure. Increase in the pressure or use of benzylamine as additive led to a gradual decrease in the enantiomeric excess and eventually inversion of the sense of the enantioselectivity. On the contrary, the optical purity of the product resulting from the hydrogenation of 2‐acetamidoacrylic acid was significantly increased by addition of benzylamine to the reaction mixture. Enantiomeric excess values up to 58 % and 60 % were obtained over Pd/Al2O3 modified by cinchonidine and cinchonine, respectively. These optical purities are the best obtained in the hydrogenation of dehydroamino acid derivatives over chirally modified heterogeneous metal catalysts.
A Novel Propargylation/Cycloisomerization Tandem Process Catalyzed by a Ruthenium(II)/Trifluoroacetic Acid System: One‐Pot Entry to Fully Substituted Furans from Readily Available Secondary Propargylic Alcohols and 1,3‐Dicarbonyl Compounds
Authors: Cadierno Victorio , Gimeno José , Nebra Noel
Published: February 2007

A simple and highly efficient method for the preparation of tetrasubstituted furans starting from readily accessible propargylic alcohols and commercially available 1,3‐dicarbonyl compounds has been developed. The process, which proceeds in a one‐pot manner, involves the initial propargylation of the 1,3‐dicarbonyl compound promoted by trifluoroacetic acid, and subsequent cycloisomerization of the resulting γ‐ketoalkyne catalyzed by the 16‐electron allyl‐ruthenium(II) complex [Ru(η3‐2‐C3H4Me)(CO)(dppf)][SbF6].
A Basic Water Quality Model for the River Neckar: Part 1 – model development, parameter sensitivity and identifiability, calibration and validation
Authors: Haag Ingo
Published: January 2007

In order to simulate and forecast dissolved oxygen (DO) in the central part of River Neckar, we developed a Basic Water Quality Model (BWQM). The present paper gives a comprehensive description of model development, model structure along with the governing equations, sensitivity and identifiability analyses as well as calibration and validation. The development of BWQM was guided by two major restrictions: it has to account for all relevant processes affecting DO, and it should only be based on readily available data and system knowledge. These restrictions led to a model, calculating nine state variables, including DO, phytoplankton, nutrients, and biochemical oxygen demand. However, due to limited data, the representation of phytoplankton is quite simple. A local sensitivity analysis led to a subset of five parameters, which are much more sensitive than the 22 other parameters. These five parameters are all closely connected with phytoplankton dynamics, highlighting the importance of phytoplankton for the DO budget. On the basis of an a priori identifiability analysis, four out of the five most sensitive parameters were chosen for model calibration. The calibrated model performed well in simulating DO and phytoplankton. Given the data availability and the present state of system knowledge, BWQM comes close to representing the optimal model with respect to predicting DO and phytoplankton.