bluuebunny/crossref_metadata_2025 huggingface dataset:
Remote Raman Spectroscopy for Planetary Exploration: A Review
Authors: Angel S. Michael , Gomer Nathaniel R. , Sharma Shiv K. , McKay Chris
Published: January 2012

In this review, we discuss the current state of standoff Raman spectroscopy as it applies to remote planetary applications, including standoff instrumentation, the technique's ability to identify biologically and geologically important analytes, and the feasibility to make standoff Raman measurements under various planetary conditions. This is not intended to be an exhaustive review of standoff Raman and many excellent papers are not mentioned. Rather it is intended to give the reader a quick review of the types of standoff Raman systems that are being developed and that might be suitable for astrospectroscopy, a look at specific analytes that are of interest for planetary applications, planetary measurement opportunities and challenges that need to be solved, and a brief discussion of the feasibility of making surface and plume planetary Raman measurements from an orbiting spacecraft.
Radon capture with silver exchanged zeolites
Authors: Hedström Hanna , Foreman Mark , Ekberg Christian , Ramebäck Henrik
Published: January 2012

To enable laboratory work with larger amounts of 226Ra and its decay products, e.g., 222Rn and its daughters, these need to be captured in order to avoid unnecessary alpha contamination of the laboratory work space and ventilation systems.

In this study, radon gas was pumped through a column filled with the silver exchanged zeolite called “silver exchanged molecular sieves 13X” (Ag84Na2[(AlO2)86(SiO2)106]·xH2O). After exposure to radon, the radioactivity of the zeolite was measured repeatedly using high resolution gamma spectrometry. It was shown that radon was captured and retained in the silver exchanged zeolite. The zeolites´ ability to retain radon was decreased by formation of metallic silver, caused by ionizing radiation. However, the zeolite was regenerated by heating and its radon capture ability was restored. The daughters of radon are not in gas phase and will hence stay on the column.
A Longitudinal Study on Raynaud's Phenomenon in Workers Using an Impact Wrench
Authors: Aiba Yoko , Yamamoto Kenya , Ohshiba Satoshi , Ikeda Kazuhiro , Morioka Ikuharu , Miyashita Kazuhisa , Shimizu Hidesuke
Published: January 2012

A Longitudinal Study on Raynaud's Phenomenon in Workers Using an Impact Wrench: Yoko AIBA, et al. Occupational Health Research and Development Center, Japan Industrial Safety and Health Association—

Objectives

The purpose of this study was to clarify the occurrence of Raynaud's phenomenon among workers using an impact wrench for a long time.

Methods

The subjects were 704 workers regularly using an impact wrench and taking special medical examinations for vibration syndrome from 1981 to 2008. Raynaud's phenomenon was observed in 39 subjects during the observation period.

Results

The mean operating years at the occurrence of Raynaud's phenomenon was 25.5 ± 8.3 (standard deviation) yr. The mean total operating time (geometric average) at the occurrence of Raynaud's phenomenon was 11,689 h. By the person‐year method, the incidence rate of Raynaud's phenomenon was 6.27 persons per 1,000 person‐years. The estimated risk of developing Raynaud's phenomenon did not increase until 12 years after starting to operate an impact wrench but increased exponentially after that. The vibration level of an impact wrench (from 4.9 m/s2to 22.6 m/s2) exceeded the occupational exposure limit value (4.9 m/s2). Various countermeasures, such as introducing automatically apparatus and keeping the working environment warm to protect from cold exposure, were taken at the factory.

Conclusions

These findings showed that the rate of occurrence of Raynaud's phenomenon was not high, although the vibration level of the impact wrench was high. This may result from various countermeasures to prevent the occurrence of Raynaud's phenomenon. A long period of exposure to vibration had the potential to lead to the occurrence of Raynaud's phenomenon even under various countermeasures.
Neonatal Drug Withdrawal
Authors: Hudak Mark L. , Tan Rosemarie C. ,   THE COMMITTEE ON DRUGS,   THE COMMITTEE ON FETUS AND NEWBORN, Frattarelli Daniel A. C. , Galinkin Jeffrey L. , Green Thomas P. , Neville Kathleen A. , Paul Ian M. , Van Den Anker John N. , Papile Lu-Ann , Baley Jill E. , Bhutani Vinod K. , Carlo Waldemar A. , Cummings James , Kumar Praveen , Polin Richard A. , Wang Kasper S. , Watterberg Kristi L.
Published: January 2012

Maternal use of certain drugs during pregnancy can result in transient neonatal signs consistent with withdrawal or acute toxicity or cause sustained signs consistent with a lasting drug effect. In addition, hospitalized infants who are treated with opioids or benzodiazepines to provide analgesia or sedation may be at risk for manifesting signs of withdrawal. This statement updates information about the clinical presentation of infants exposed to intrauterine drugs and the therapeutic options for treatment of withdrawal and is expanded to include evidence-based approaches to the management of the hospitalized infant who requires weaning from analgesics or sedatives.
School-Based Health Centers and Pediatric Practice
Authors:   COUNCIL ON SCHOOL HEALTH
Published: January 2012

This Policy Statement was revised. See https://doi.org/10.1542/peds.2021-053758.

School-based health centers (SBHCs) have become an important method of health care delivery for the youth of our nation. Although they only represent 1 aspect of a coordinated school health program approach, SBHCs have provided access to health care services for youth confronted with age, financial, cultural, and geographic barriers. A fundamental principle of SBHCs is to create an environment of service coordination and collaboration that addresses the health needs and well-being of youth with health disparities or poor access to health care services. Some pediatricians have concerns that these centers are in conflict with the primary care provider’s medical home. This policy provides an overview of SBHCs and some of their documented benefits, addresses the issue of potential conflict with the medical home, and provides recommendations that support the integration and coordination of SBHCs and the pediatric medical home practice.
Dispensing Medications at the Hospital Upon Discharge From an Emergency Department
Authors: Yamamoto Loren G. , Manzi Shannon ,   THE COMMITTEE ON PEDIATRIC EMERGENCY MEDICINE, Shaw Kathy N. , Ackerman Alice D. , Chun Thomas H. , Conners Gregory P. , Dudley Nanette C. , Fein Joel A. , Fuchs Susan M. , Moore Brian R. , Selbst Steven M. , Wright Joseph L.
Published: January 2012

This Technical Report was revised. See https://doi.org/10.1542/peds.2023-062144.

Although most health care services can and should be provided by their medical home, children will be referred or require visits to the emergency department (ED) for emergent clinical conditions or injuries. Continuation of medical care after discharge from an ED is dependent on parents or caregivers’ understanding of and compliance with follow-up instructions and on adherence to medication recommendations. ED visits often occur at times when the majority of pharmacies are not open and caregivers are concerned with getting their ill or injured child directly home. Approximately one-third of patients fail to obtain priority medications from a pharmacy after discharge from an ED. The option of judiciously dispensing ED discharge medications from the ED’s outpatient pharmacy within the facility is a major convenience that overcomes this obstacle, improving the likelihood of medication adherence. Emergency care encounters should be routinely followed up with primary care provider medical homes to ensure complete and comprehensive care.
New Electric Tomography Scheme and Algorithms for Fast Recognition of Compound Structures
Authors: Grebennikov Alexandre
Published: January 2012

Necessity of recognition of compound structures appears in different applications. Electrical tomography is one of perspective approach for investigation of material structures. A new special measurement scheme in electric tomography is proposed for the domain as a circle. This scheme opens possibility to construct electric tomography apparatus with faster computer recognition of structure of compounds materials, using General Ray algorithms. Computer simulation of this scheme is realised with MATLAB software and justified by numerical experiments on examples, related with electrical tomography.
Aluminum Alloy Formation and Impacts in Advanced Replacement Metal Gate Process
Authors: Xu K. , Wang Y. , Shen S.H. , Xia X. , Tu W.Ch. , Karuppiah L. , Yang H. , Ge Z. , Lei Y. , Allen M. , Yoshida N. , Chang L.W. , Liu B. , Okazaki M. , Brand A.
Published: January 2012

For the gate last approach of a high K metal gate scheme used in advanced CMOS technology, various materials were tested as wetting layers to allow Aluminum (Al) gap fill at gate widths of10 to 45 nanometers. In this study, Titanium (Ti) and Cobalt (Co) were investigated as a wetting layer for Al gap fill. It was discovered that Al-Ti and Al-Co alloys were formed during high temperature Al deposition. Alloys were characterized using XRD. Alloy’s impacts on line resistivity and subsequent Al Chemical Mechanical Polish (Al CMP) were also investigated. In addition, a model was established to predict the alloy type and alloy mole% with respect to feature size. The predicted Al mole% by this model correlated very well with 1) line resistivity trend and 2) morphologies. The model also predicted that due to Al lower electro-chemical potential than Ti, Co or its alloys, galvanic corrosion could take place depending on the chemical environment in the Al CMP slurry. Different slurry or cleaning chemical may reduce or increase the risk of galvanic corrosion. The knowledge gained with the help of the model provides clear directions on selection criteria for wetting layers, optimization for deposition processes and Al CMP consumable design to meet the challenges.
Phonons and Crystalline Structure of Hg1−xCdxS e Alloys (0 <x≤ 0.5)
Authors: Miranda David A. , López-Rivera S. A. , Power Ch. , Henao J. A. , Macías M. A.
Published: January 2012

Phonons and crystalline structures of Hg1−xCdxSe alloys (0 ≤x≤ 0.5) were studied by Raman spectroscopy and X-ray powder diffraction patterns at 298K. The crystalline alloys were prepared by a special combination of synthesis and the Bridgman method. Experimental data showed a face-centered cubic structure,$F\overline 4 \,3\,m$(No. 216), for all samples, exhibiting a linear dependence for Cd molar fraction,x, for cell parameters,a, and the mass densities,ρ. Phonon frequencies were analyzed using the Romevi-Romevi model for phonons in multicomponent alloys, obtaining a fair agreement with experimental data. Furthermore, an algorithm to implement the Romevi-Romevi model is proposed.
Sol-Gel Preparation, Characterization and Photocatalytic Activity of Nanostructured TiO2 Nanoparticles
Authors: Carrera R. , Castillo S.
Published: January 2012

To establish a promising method for the purification of air containing volatile organic compounds, TiO2 nanoparticles with interesting physicochemical properties were prepared by the sol-gel method to perform the photocatalytic decomposition of acetaldehyde. The obtained samples were characterized by the x-ray diffraction -Rietveld refinement, transmission electron microscopy (TEM) and the Brunauer, Emmet and Teller (BET) model. According to the results, the sample that presented the highest activity (96.4%) in the photocatalytic oxidation of acetaldehyde was the one annealed at 200 °C. This material showed the presence of a mixture of the anatase (higher proportion) and brookite phases, nanometric crystal size (7.03 nm) and high surface area (189 m2g-1). The physicochemical properties present in the TiO2-P-200°C nanoparticles suggest that they may establish a photoassisted reaction process for air purification, in which volatile organic compounds are photocatalitically decomposed.
Evaluation of Sulfidation Resistance of Atomized Fe40Al Based Intermetallics
Authors: Espinosa-Medina M. A. , Carbajal de la Torre G. , Martínez-Villafañe A. , González-Rodríguez J.G.
Published: January 2012

The isothermal oxidation-sulfidation of Fe-40Al based intermetallics alloys in N2/SO2 gas mixture at 625, 700 and 775°C were evaluated. Fe40Al, Fe40Al+0.1B, Fe40Al+0.1B+10Al2O3 alloys were produced by atomization and deposition. Isothermal gas exposition was reached during 48 hours. FeAl based alloys showed good sulfidation resistance, presenting both small weight gain and weight change fluctuations. At 625°C, the Fe40Al+0.1B alloy had the biggest weight gain; on the other hand the Fe40Al alloy exhibited the biggest sulfidation resistance. At 700 and 775°C, the Fe40Al+0.1B alloy presented the smallest weight gain, however Fe40Al alloy presented higher weight gain, that is to say, the smallest sulfidation resistance at those temperatures. The variation in the weight gain curves were discussed in terms of formation and detachment of sulfides, and by local attack on the alloy surface as the temperature increasing. The results are supplemented with characterization by SEM and analysis of X-rays dispersion.
Transmission of Dirac Electrons Through Graphene Multilayers with Gaussian Profile
Authors: Aguilar-Hernández J. A. , Madrigal-Melchor J. , Martínez-Orozco J. C. , Rodríguez-Vargas I.
Published: January 2012

In this work, we use the T-matrix method to study the tunneling of Dirac electrons through graphene multilayers. A graphene sheet is deposited on top of slabs of SiO2-SiC substrates, of which we applied a Gaussian distribution in the size width of the SiC substrate. We calculate the transmittance as a function of energy for different incident angles and different number of layers of the Gaussian distribution. We obtain different stop-band regions. These regions are wider when the width of the barrier is increased. Furthermore, it is possible to tune the width and the position of stop-band with the angle of incidence, the σ value of the Gaussian distribution, and the difference between the maximum-minimum sizes of the barrier.
Application of the International Classification of Functioning, Disability, and Health–Children and Youth Version (ICF-CY) to Cleft Lip and Palate
Authors: Neumann Sandra , Romonath Roswitha
Published: January 2012

Objective

In recent health policy discussions, the World Health Organization has urged member states to implement the International Classification of Functioning, Disability, and Health: Children and Youth Version in their clinical practice and research. The purpose of this study was to identify codes from the International Classification of Functioning, Disability, and Health: Children and Youth Version relevant for use among children with cleft lip and/or palate, thereby highlighting the potential value of these codes for interprofessional cleft palate-craniofacial teams.

Design

The scope of recent published research in the area of cleft lip and/or palate was reviewed and compared with meaningful terms identified from the International Classification of Functioning, Disability, and Health: Children and Youth Version. In a five-step procedure, a consensus-based list of terms was developed that was linked separately to International Classification of Functioning, Disability, and Health: Children and Youth Version categories and codes. This provided a first draft of a core set for use in the cleft lip and/or palate field.

Conclusions

Adopting International Classification of Functioning, Disability, and Health: Children and Youth Version domains in cleft lip and/or palate may aid experts in identifying appropriate starting points for assessment, counseling, and therapy. When used as a clinical tool, it encourages health care professionals to go beyond treatment and outcome perspectives that are focused solely on the child and to include the children's environment and their familial/societal context. In order to establish improved, evidence-based interdisciplinary treatments for children with cleft lip and/or palate, more studies are needed that seek to identify all the influencing conditions of activities, children's participation, and barriers/facilitators in their environments.
Trajectories of change in sagebrush steppe vegetation communities in relation to multiple wildfires
Authors: Davies G. M. , Bakker J. D. , Dettweiler-Robinson E. , Dunwiddie P. W. , Hall S. A. , Downs J. , Evans J.
Published: January 2012

Repeated perturbations, both biotic and abiotic, can lead to fundamental changes in the nature of ecosystems, including changes in state. Sagebrush steppe communities provide important habitat for wildlife and grazing for livestock. Fire is an integral part of these systems, but there is concern that increased ignition frequencies and invasive species are fundamentally altering them. Despite these issues, the majority of studies of fire effects in systems dominated by Artemisia tridentata wyomingensis have focused on the effects of single burns. The Arid Lands Ecology Reserve (ALE), in south‐central Washington (USA), was one of the largest contiguous areas of sagebrush steppe habitat in the state until large wildfires burned the majority of it in 2000 and 2007. We analyzed data from permanent vegetation transects established in 1996 and resampled in 2002 and 2009. Our objective was to describe how the fires, and subsequent postfire restoration efforts, affected communities' successional pathways. Plant communities differed in response to repeated fire and restoration; these differences could largely be ascribed to the functional traits of the dominant species. Low‐elevation communities, previously dominated by obligate seeders, moved furthest from their initial composition and were dominated by weedy, early‐successional species in 2009. Higher‐elevation sites with resprouting shrubs, native bunchgrasses, and few invasive species were generally more resilient to the effects of repeated disturbances. Shrub cover has been almost entirely removed from ALE, although there was some recovery where communities were dominated by resprouters. Bromus tectorum dominance was reduced by herbicide application in areas where it was previously abundant, but it increased significantly in untreated areas. Several resprouting species, notably Phlox longifolia and Poa secunda, expanded remarkably following competitive release from shrub canopies and/or abundant B. tectorum. Our results suggest that community dynamics can be understood through a state and transition model with two axes (shrub/grass and native/invasive abundance), although such models also need to account for differences in plant functional traits and disturbance regimes. We use our results to develop a conceptual model that will be validated with further research.
Soil metabolic pulses: water, substrate, and biological regulation
Authors: Jenerette G. Darrel , Chatterjee Amitava
Published: January 2012

Pulses of metabolic activity are a common ecological response to intermittently available resources, and in soils these pulses often occur in response to wetting. To better understand variation in soil pulses, we conducted a distributed field experiment at seven sites along a 2200‐m elevation transect in southern California, USA. Treatments included both water and water + substrate additions and two measurements of soil respiration within one hour. These experiments were repeated 11 times throughout 2009–2010. Additions of substrate led to consistently higher pulse fluxes, exceeding 10 μmol CO2·m−2·s−1, than additions of water alone. These results support a sequential limitation by two resources where an initial limiting resource acts as a switch and, after activation, processes are regulated by a second resource. In contrast to general expectations of increasing pulses with higher soil organic matter (SOM), pulses exhibited strong scale dependencies. Pulses during the summer period and SOM were correlated positively within sites and negatively between sites. This cross‐scale divergence implies that, at low elevations, the proportion of SOM available for pulse metabolism was a much larger fraction than at higher elevations. With expected climate changes leading to more frequent drying–wetting cycles, regulation of metabolic pulses will increasingly influence long‐term biogeochemical dynamics.
THE ISOLATION OF MOTIVATIONAL, MOTORIC, AND SCHEDULE EFFECTS ON OPERANT PERFORMANCE: A MODELING APPROACH
Authors: Brackney Ryan J. , Cheung Timothy H. C. , Neisewander Janet L. , Sanabria Federico
Published: January 2012

Dissociating motoric and motivational effects of pharmacological manipulations on operant behavior is a substantial challenge. To address this problem, we applied a response‐bout analysis to data from rats trained to lever press for sucrose on variable‐interval (VI) schedules of reinforcement. Motoric, motivational, and schedule factors (effort requirement, deprivation level, and schedule requirements, respectively) were manipulated. Bout analysis found that interresponse times (IRTs) were described by a mixture of two exponential distributions, one characterizing IRTs within response bouts, another characterizing intervals between bouts. Increasing effort requirement lengthened the shortest IRT (the refractory period between responses). Adding a ratio requirement increased the length and density of response bouts. Both manipulations also decreased the bout‐initiation rate. In contrast, food deprivation only increased the bout‐initiation rate. Changes in the distribution of IRTs over time showed that responses during extinction were also emitted in bouts, and that the decrease in response rate was primarily due to progressively longer intervals between bouts. Taken together, these results suggest that changes in the refractory period indicate motoric effects, whereas selective alterations in bout initiation rate indicate incentive‐motivational effects. These findings support the use of response‐bout analyses to identify the influence of pharmacological manipulations on processes underlying operant performance.
Anaerobic biodegradation of gasoline oxygenates in soils
Authors: Yeh Carol K. , Novak John T.
Published: January 2012

ABSTRACT:  This study evaluated the biodegradation of methyl tertiary butyl ether (MTBE), ethyl tertiary butyl ether (ETBE), and tertiary butyl alcohol (TBA)—three chemicals used as gasoline additives. The biodegradation under sulfate reducing, methanogenic and denitrifying conditions was measured in static soil and water microcosms using soils of different origin and varying characteristics. The results indicate that TBA was the easiest compound to biodegrade, whereas MTBE was the most recalcitrant. It is thought that cleavage of the ether bond in MTBE and ETBE is the first and rate‐limiting step in the degradation of these organics. TBA degradation was enhanced by nutrient addition in the nutrient poor soils but hindered by the presence of other easily‐degraded organic compounds. Degradation of MTBE and ETBE occurred only in the soil with the lowest organic matter content and with a pH around 5.5. No degradation of MTBE and ETBE was observed in the organic‐rich soils, and in the organically poor soil the addition of easily degradable organic compounds inhibited MTBE and ETBE degradation.
Removal of zinc and manganese from contaminated water with cyanobacteria mats
Authors: Bender J. , Gould J. P. , Vatcharapijarn Y. , Young J. S. , Phillips P.
Published: January 2012

ABSTRACT:  Cyanobacteria mats, developed for metal tolerance, were allowed to grow in columns packed with glass wool. Resulting columns contained complex, self‐organized ecosystems dominated by cyanobacteria (blue‐green algae). This immobilized cell system was assessed for its potential in removing zinc and manganese (mixed solution) from contaminated water. Twelve applications (days 2 to 13 of the experiment) of 0.3‐L/day volumes containing 14 mg/L of each metal resulted in average removals of 96% zinc and 85% manganese with a 3‐hour retention time. Final zinc and manganese concentrations in the mat (mg/g) were 10.13 and 10.30, respectively. Unique ecosystem conditions suggest that metal removal likely involved heterogenous chemical zones that resulted in the simultaneous deposition of zinc and manganese as stable, nontoxic precipitates.
The effects of freeze‐drying and storage on phenol degradation
Authors: Gaiek Roberta L. , Lange Clifford R. , Weber A. Scott
Published: January 2012

ABSTRACT:  Freeze‐drying and storage were found to affect the performance of a microbial supplement cultured for phenol biodegradation. After freeze‐drying, a lag in phenol degradation was observed which increased with storage. The lag was attributed to reductions in culture viability and lags in enzyme activity, both of which increased with storage. In addition, a switch in the primary pathway for aromatic ring cleavage from catechol 2,3‐oxygenase to catechol 1,2‐oxygenase occurred after freeze‐drying. While freeze‐drying and storage adversely affected viability and resulted in both a switch and lag in enzyme activity, increases in the maximum specific growth constant, µm, also were observed with this treatment. Both the observed lag in phenol degradation and increases in µm were simulated numerically.
Activated carbon adsorption of phenolics in oxic systems: Effect of pH and temperature variations
Authors: Nakhla G. , Abuzaid N. , Farooq S.
Published: January 2012

ABSTRACT:  Studies were undertaken to determine the role of solution pH and temperature in the enhancement of the adsorptive capacity of GAC for phenol and ocresol stemming from oxygen‐induced polymerization. Anoxic and oxic isotherms for the sorbates were conducted at various pHs and temperatures. Adsorption isotherms were conducted at room temperature (21 °C) and pHs of 3,7, and 11. Low pH favors physical adsorption, measured by the anoxic capacity, while pH 11 promoted polymerization. The optimum pH for adsorption of phenolics under oxic conditions was pH 7. Isotherms were also conducted at neutral pH and temperatures of 8°, 21°, and 35°C. Lower temperatures favored physical adsorption and higher temperature achieved significant enhancement in capacity under oxic conditions. However, actual oxic isotherms capacities at 8° and 21 °C, were identical. The sorption capacity could increase by more than two fold by changing solution pH and temperature.
The effect of pore size on transfer capabilities, fouling tendencies, and cleaning of ceramic air diffusers
Authors: Redmon David T. , Melcer Henryk , Ellefson Gerald V. , Ewing Lloyd
Published: January 2012

ABSTRACT:  A study of the effect of fouling on the standard oxygen transfer efficiency (SOTE) of ceramic diffusers of four different pore sizes was conducted at the Monroe, Wis. wastewater treatment plant over a 2‐year period. Four pilot test headers were installed in the plant aeration tanks each containing four diffusers of one pore size. Only minor changes in SOTE, bubble release vacuum (BRV), and dynamic wet pressure (DWP) were observed indicating that the fouling phenomenon at Monroe was not progressive. The adverse effects of fouling with respect to back pressure and SOTE were found to be less than might have been predicted from the literature. The cleaning procedure used in the study, involving a combination of high pressure water spraying with liquid acid treatment, followed by additional spraying, resulted in nearly complete restoration of the diffusers' original characteristics.
Verification of the fate of a volatile organic compound in activated sludge
Authors: Melcer Henryk , Bedford Wayne K.
Published: January 2012

ABSTRACT:  The fate of the volatile organic compound, 1,4‐dichlorobenzene (DCB) was examined in a bench‐scale activated sludge system. A shift in removal mechanism, from stripping to biodegradation, was observed at different stages of acclimation. The response of an unacclimated sludge to DCB perturbations showed a preferential loss of DCB by stripping. Radiolabeled DCB tracer studies with an acclimated sludge demonstrated 10 to 20% mineralization of DCB, 25 to 30% loss by stripping, and the remaining DCB transformed to intermediate metabolites that were found in the mixed liquor and effluent. Biodegradation rates determined for DCB fell into two distinct ranges depending on the degree of sludge acclimation.
Determination of ferric chloride dose to control struvite precipitation in anaerobic sludge digesters
Authors: Mamais Daniel , Pitt Paul A. , Cheng Yao Wen , Loiacono Jon , Jenkins David
Published: January 2012

ABSTRACT:  Anaerobic digestion of sludges favors the formation of struvite because ammonia, phosphate, and magnesium are solubilized by the digestion process. Struvite (MgNH4P04 · 6H20(s)) can cause problems through scale formation. This paper provides a rational method for predicting the optimum FeCl3 dose for preventing struvite formation during anaerobic digestion. Based on continuous flow anaerobic digestion experiments, the minimum dose to prevent struvite formation in the San Francisco Southeast Water Pollution Control Plant is 13.5 mM FeCl3/L or 100 kg FeCl3/ton total solids (TS). Approximately 68% of the total magnesium and total phosphorus present in the feed was available for chemical precipitation and the average ratio of soluble P04‐P removed to Fe added was 0.37. Additional iron demand was attributed to FeS(s) and FeC03(s) precipitation. Anaerobic sludge digestion batch studies showed similar soluble P04‐P removal efficiencies by FeCl3 and FeS04 dosing, indicating that Fe(III) is reduced readily to Fe(II) in anaerobic sludge digesters.
Comparative analyses of diffusion coefficients for different extraction processes from thyme
Authors: Petrovic Slobodan , Ivanovic Jasna , Milovanovic Stoja , Zizovic Irena
Published: January 2012

This work was aimed to analyze kinetics and mass transfer phenomena for
different extraction processes from thyme (Thymus vulgaris L.) leaves.
Different extraction processes with ethanol were studied: Soxhlet extraction
and ultrasound-assisted batch extraction on the laboratory scale as well as
pilot plant batch extraction with mixing. The extraction processes with
ethanol were compared to the process of supercritical carbon dioxide
extraction performed at 10 MPa and 40?C. Experimental data were analyzed by
mathematical model derived from the Fick?s second law to determine and
compare diffusion coefficients in the periods of constant and decreasing
extraction rate. In the fast extraction period, values of diffusion
coefficients were one to three orders of magnitude higher compared to those
determined for the period of slow extraction. The highest diffusion
coefficient was reported for the fast extraction period of supercritical
fluid extraction. In the case of extraction processes with ethanol,
ultrasound, stirring and extraction temperature increase enhanced mass
transfer rate in the washing phase. On the other hand, ultrasound contributed
the most to the increase of mass transfer rate in the period of slow
extraction.
Development of a robotic device for upper limb stroke rehabilitation: A user-centered design approach
Authors: Lu Elaine C. , Wang Rosalie , Huq Rajibul , Gardner Don , Karam Paul , Zabjek Karl , Hebert Debbie , Boger Jennifer , Mihailidis Alex
Published: January 2012

Stroke is one of the major causes of permanent adult disability. Stroke frequently affects motor control of the arm, leading to diffculties in doing activities of daily living. This research focuses on developing an upper limb rehabilitation robotic prototype through user-centered design to aid stroke survivors in rehabilitating their arm. To gather requirements from end users, stroke therapy sessions were observed and a survey of stroke therapists was conducted. End user requirements were evaluated to determine technical targets for the mechanical design of the prototype. Evaluation of the prototype was done with stroke therapists in a focus group and a preliminary biomechanical study. As user-centered design would require more iterations of design, testing and evaluation, this project reports a first step in developing an affordable, portable device, which could increase access to stroke rehabilitation for the arm.
Public Preferences on the Use of Visualization in the Public Involvement Process in Transportation Planning
Authors: Cheu Ruey Long , Valdez Marilyn , Kamatham Srivatsava , Aldouri Raed
Published: January 2012

This study examines public preferences on the use of visualization techniques to involve the public in transportation planning. Two projects were selected, and prototype two-dimensional, three-dimensional, and four-dimensional visualization models were developed. The models were presented at public meetings where stated preference surveys were conducted. The same models were also presented in a survey conducted via the Internet. A majority of both the 31 questionnaire respondents and the 136 Internet-based survey respondents ranked the two-dimensional, three-dimensional, and four-dimensional visualization techniques in increasing order of their abilities to convey the proposed project concepts. More than 71% of the respondents thought that transportation planning agencies should devote more time and budget to develop advanced visualization models to encourage public participation. In addition, more than 75% of the respondents indicated that they would be more willing to participate and encourage others to participate in the public involvement process if better visualization tools were used.
Parking Requirements in Some Major Asian Cities
Authors: Barter Paul A.
Published: January 2012

Parking requirements are a hotly debated element of parking policy. Yet such requirements are common worldwide. Little effort had been made, however, to make international comparisons that could place local policies into wider perspective. This study focused on parking requirement policies in 14 cities in South Asia, East Asia, and Southeast Asia. Cities in these regions have tended to be high in urban density, relatively low in car ownership, and, in some cases, strongly transit-oriented in their urban transport systems. In the West, localities with these characteristics often reject the suburban-style parking policy that requires minimum parking, and adopt alternatives. Nevertheless, all Asian cities in the study did enforce such parking requirements on building developments. This surprising enforcement result raised questions. Are these Asian parking requirement policies really similar to those in the West? Are criticisms of Western policies relevant in Asia? Are there lessons to be drawn from parking requirement practices in this region? Such questions were addressed through comparisons of parking requirement policies in the 14 Asian cities (and with reference to Western practice, especially in North America and Australia). The study drew on information collected for a wider study of parking policy in Asia commissioned by the Asian Development Bank. The results revealed diversity, including some distinctive approaches. The findings should provide insights that are useful in debates on parking policy reform, inside and outside the region.
Location, Regional Accessibility, and Price Effects
Authors: Iacono Michael , Levinson David
Published: January 2012

Regional location factors exert a strong influence on urban property markets, and measures of accessibility are foremost among them. More local influences, such as proximity to urban highway links, also may positively or negatively influence the desirability of a location. This study used a cross section of home sales in Hennepin County, Minnesota, from the years 2001 through 2004, along with a set of disaggregate regional accessibility measures, to estimate the value of access to employment and resident workers. The effects, whether as amenity or disamenity, were estimated for locations near major freeway links that had recently undergone major construction to add capacity (or were scheduled to undergo such construction) at the time of the home sales. The richness of the home sales data set allowed for control of a number of structural attributes, as well as some site characteristics. Additional neighborhood characteristics (such as income levels and local educational quality) were added from supplemental data sources. Empirical results indicated that households highly valued access to employment. Access to other resident workers (i.e., competition for jobs) was considered a disamenity. Proximity to local highway access points associated positively with sale price, whereas proximity to the highway link itself associated negatively with that price. The study concluded with some implications for research and practice of the concept and measurement of the relationship between location and land value.
Exploration of Location Influences on Firm Survival Rates with Parametric Duration Models
Authors: Manzato Gustavo G. , Arentze Theo A. , Timmermans Harry J. P. , Ettema Dick
Published: January 2012

This study explored the influences of location on business firm survival rates with the use of parametric duration models applied to a data set. Of the variables included, those found to be the most significant were accessibility to infrastructure supply, regional effects, demographic and economic aspects, and rent price. Analyses also were depicted by firm type (economic activity sector) along with interactions between them and some location attributes. The study led to a better understanding of firm survival patterns with respect to urban characteristics. The results presented in this paper are part of a demographic approach, which in turn is part of a multiagent system to simulate the coevolution of firm dynamics and changes in activity-travel patterns.
Incremental Integration of Land Use and Activity-Based Travel Modeling
Authors: Wang Liming , Waddell Paul , Outwater Maren L.
Published: January 2012

Recent advances in activity-based travel modeling and integrated land use and transportation modeling have significantly advanced the understanding of and the capacity to model location choices and travel behavior more realistically. These advances, however, come with greater data requirements, and the risk and the substantial cost involved with adoption of these models have slowed their move to operational use. The purpose of this research was twofold. First, the study addressed one aspect of an incremental approach that more carefully balanced the risks and benefits of moving operational models in new directions: replacement of the choice model of home-based work destination in the four-step travel model system with a pair of choice models at the level of the individual worker. The new choice models were implemented as long-term choices in the linked land use model system. Second, the models were used to provide a way to derive matches between workers and their workplace with commonly available data. These matches complemented synthetic populations and provided a key input for activity-based travel models. The models predicted whether a worker would choose to work at home on a long-term basis; if he or she did not, an out-of-home job was chosen. These models linked an individual worker to a specific job at a workplace and therefore directly predicted commuting patterns. The paper presents the model specifications, estimation results, and results of validation of the models against observed commuting data from the Census Transportation Planning Package. The model reproduced observed commuting flows well, and computational performance was fast, even though the model operated at the level of the individual worker and job.
Integration of Activity-Based and Agent-Based Models
Authors: Bekhor Shlomo , Dobler Christoph , Axhausen Kay W.
Published: January 2012

This study explored the possibility of integrating an operational activity-based model and a dynamic traffic assignment framework. The Tel Aviv, Israel, activity-based model and parts of the functionality of the MATSim agent-based framework were used in an attempt to draw on the best features of both approaches: the disaggregate demand representation from the activity-based model and the disaggregate supply representation of the agent-based framework. The study used the person–activity schedule produced by the activity-based model directly and thus eliminated the need to aggregate origin–destination matrices. This paper compares results produced by this combination with those of a static assignment of the Tel Aviv model, which showed a good fit at the aggregate level. The purpose of the paper is to advance the fully disaggregate implementation of activity-based models. The paper represents a step toward this general goal.
Forecasting Location of New Housing in Integrated Models of Land Use
Authors: Dong Hongwei , Gliebe John
Published: January 2012

Most housing market submodels in extant integrated models of land use have focused on the demand for dwelling units by household, with scant attention paid to the supply side of the market represented by individual home developers. This study tried to fill this gap by developing and comparing three models that forecast the development of single-family homes. The three models were characterized separately on the basis of the specifications for location of the new housing choice: (a) assumed market homogeneity and atomization of development projects (Model 1), (b) deterministic market segmentation and synthesis of projects (Model 2), and (c) probabilistic market segmentation and synthesis of projects by use of a latent class approach (Model 3). Examination of the forecast results showed that all three models could successfully capture the basic spatial pattern of single-family-home developments in the region. Although Models 2 and 3 were more sophisticated and more theoretically appealing, they did not produce better forecast results than Model 1 because of some practical issues, including the lack of developer information for forecast years, the small sample size of large projects, the physics of forecasting a small number of large projects across a large number of location alternatives, the need to sample large numbers of alternatives when nonmultinomial logit models were estimated, and the difficulty of using dummy variables in latent class models. In this particular context, the simpler model specification proved to be both easier to implement and more accurate. Models 2 and 3, however, were expected to perform better when those practical issues are solved, at least partially, in further research.
Historical Validation of Integrated Transport–Land Use Model System
Authors: Miller Eric J. , Farooq Bilal , Chingcuanco Franco , Wang David
Published: January 2012

The Integrated Land Use, Transportation, Environment (ILUTE) model system is an agent-based microsimulation model for the greater Toronto–Hamilton, Ontario, Canada, area. The model system uses disaggregate models of spatial socioeconomic processes to evolve the state of the greater Toronto–Hamilton area from a known base case to a predicted end state in 1-year time steps. ILUTE has reached a state of operational implementation in which historical validation runs are being undertaken. The model runs start with 100% of the population of people, families, households, and dwelling units in the greater Toronto area that was synthesized for the year 1986. Twenty-year historical simulations (1986 to 2006) have been run, with model outputs being compared with Canadian census data and Transportation Tomorrow Survey data for 1991, 1996, 2001, and 2006. This paper presents recent findings from these historical validation tests and emphasizes the system's modeling of the demographic evolution of the population and the region's housing market.
Travel by University Students in Virginia
Authors: Khattak Asad , Wang Xin , Son Sanghoon , Agnello Paul
Published: January 2012

To improve regional travel demand models, transportation engineers and planners want to represent subpopulations appropriately. A key segment of the population is university students, and their behavior is neither well understood nor well represented in travel demand models. Furthermore, universities provide a unique context for behavioral research because they are livable, are friendly to alternative travel modes, have a higher density than other contexts, and offer mixed travel modes. This study collected and analyzed data on the travel behavior of university students. With the use of an Internet-based survey instrument, the study collected data on travel behavior, sociodemographics, and context variables at four major universities in Virginia. This paper provides information about the design and implementation of the survey, the instrument structure, and a descriptive analysis of students’ personal and travel characteristics. The results indicated that the sociodemographics and travel behavior of university students were different from those of the general population. Moreover, differences in travel behavior were found between students living on campus and students living off campus and between students attending urban campuses and those attending suburban campuses. The insights gained from this study serve as a basis for further such surveys and help provide an understanding of travel behavior in and around university campuses.
Empirical Analysis of Effects of Automated Section Speed Enforcement System on Traffic Flow at Freeway Bottlenecks
Authors: Cascetta Ennio , Punzo Vincenzo , Montanino Marcello
Published: January 2012

Because speed has been recognized as the most important contributory factor in fatal road crashes, speed management has been widely implemented in several countries to improve road safety. The automated section speed enforcement system is increasingly being used as an effective way to tackle speeding, especially on motorways and in tunnels. However, the effects on traffic flow patterns of such systems remain controversial. An empirical analysis of traffic flow patterns before and after the introduction of such a system along a freeway section with recurrent congestion is presented. Gathered data consisted of point measurements at detectors and average travel speeds of each vehicle crossing the stretch. The main observed features were (a) a strong homogenization of individual speeds and of mean speeds among the lanes, (b) a reduction in the strength of the bottleneck, (c) the emergence of significant oscillations in time of traffic characteristics, and (d) a sensible reduction of travel times during the congestion pattern caused by the bottleneck moving downstream of the section. Empirical evidence suggests that driver compliance with speed limits is the key factor in analysis of such speed management systems and that their concurrent application with dynamic speed limit strategies should be thoroughly evaluated with a particular focus on this measure.
'This Is Not Our Life, It's Just a Copy of Other People's': Bedu and the Price of 'Development' in South Sinai
Authors: Gilbert Hilary
Published: January 2012

This study demonstrates the unplanned outcomes of development in an indigenous population, and the particular impact of prescribed development on bedouin livelihoods in South Sinai. In the latter half of the twentieth century, Bedu across the Middle East have adapted their livelihood strategies to the more or less authoritarian modernizing policies of nation-states. In South Sinai, in response to the rule of both Israeli and Egyptian regimes, the economy of local Bedu has shifted from pre-development, agropastoral livelihoods that provided subsistence for ten months a year, to an almost complete dependence on insecure paid work. Using data on bedouin livelihoods and household economics spanning more than forty years, I argue that state-led 'development' has brought very mixed blessings to its population. I demonstrate bedouin poverty -currently unacknowledged by the Egyptian state - for the first time, and show the relative inequality of Bedu compared to other Egyptian citizens. The failure of government to record bedouin experience creates a policy blind spot, ensuring their inequality persists.