bluuebunny/crossref_metadata_2025 huggingface dataset:
Cryptococcus neoformans induces IL-8 secretion and CXCL1 expression by human bronchial epithelial cells
Authors: Guillot Loïc , Carroll Scott F , Badawy Mohamed , Qureshi Salman T
Published: January 2008

Background

Cryptococcus neoformans(C. neoformans) is a globally distributed fungal pathogen with the potential to cause serious disease, particularly among immune compromised hosts. Exposure to this organism is believed to occur by inhalation and may result in pneumonia and/or disseminated infection of the brain as well as other organs. Little is known about the role of airway epithelial cells in cryptococcal recognition or their ability to induce an inflammatory response.

Methods

Immortalized BEAS-2B bronchial epithelial cells and primary normal human bronchial epithelium (NHBE) were stimulatedin vitrowith encapsulated or acapsularC. neoformanscultivated at room temperature or 37°C. Activation of bronchial epithelial cells was characterized by analysis of inflammatory cytokine and chemokine expression, transcription factor activation, fungal-host cell association, and host cell damage.

Results

ViableC. neoformansis a strong activator of BEAS-2B cells, resulting in the production of the neutrophil chemokine Interleukin (IL)-8 in a time- and dose-dependent manner. IL-8 production was observed only in response to acapsularC. neoformansthat was grown at 37°C.C. neoformanswas also able to induce the expression of the chemokine CXCL1 and the transcription factor CAAT/enhancer-binding protein beta (CEBP/β) in BEAS-2B cells. NHBE was highly responsive to stimulation withC. neoformans; in addition to transcriptional up regulation of CXCL1, these primary cells exhibited the greatest IL-8 secretion and cell damage in response to stimulation with an acapsular strain ofC. neoformans.

Conclusion

This study demonstrates that human bronchial epithelial cells mediate an acute inflammatory response toC. neoformansand are susceptible to damage by this fungal pathogen. The presence of capsular polysaccharide andin vitrofungal culture conditions modulate the host inflammatory response toC. neoformans. Human bronchial epithelial cells are likely to contribute to the initial stages of pulmonary host defensein vivo.
Evolution of the C4 phosphoenolpyruvate carboxylase promoter of the C4 species Flaveria trinervia: the role of the proximal promoter region
Authors: Engelmann Sascha , Zogel Corinna , Koczor Maria , Schlue Ute , Streubel Monika , Westhoff Peter
Published: January 2008

Background

The key enzymes of photosynthetic carbon assimilation in C4 plants have evolved independently several times from C3 isoforms that were present in the C3 ancestral species. The C4 isoform of phosphoenolpyruvate carboxylase (PEPC), the primary CO2-fixing enzyme of the C4 cycle, is specifically expressed at high levels in mesophyll cells of the leaves of C4 species. We are interested in understanding the molecular changes that are responsible for the evolution of this C4-characteristic PEPC expression pattern, and we are using the genus Flaveria (Asteraceae) as a model system. It is known that cis-regulatory sequences for mesophyll-specific expression of the ppcA1 gene of F. trinervia (C4) are located within a distal promoter region (DR).

Results

In this study we focus on the proximal region (PR) of the ppcA1 promoter of F. trinervia and present an analysis of its function in establishing a C4-specific expression pattern. We demonstrate that the PR harbours cis-regulatory determinants which account for high levels of PEPC expression in the leaf. Our results further suggest that an intron in the 5' untranslated leader region of the PR is not essential for the control of ppcA1 gene expression.

Conclusion

The allocation of cis-regulatory elements for enhanced expression levels to the proximal region of the ppcA1 promoter provides further insight into the regulation of PEPC expression in C4 leaves.
Analysis of Parkinson disease patients from Portugal for mutations in SNCA, PRKN, PINK1 and LRRK2
Authors: Bras Jose , Guerreiro Rita , Ribeiro Maria , Morgadinho Ana , Januario Cristina , Dias Margarida , Calado Ana , Semedo Cristina , Oliveira Catarina , Hardy John , Singleton Andrew
Published: January 2008

Background

Mutations in the genes PRKN and LRRK2 are the most frequent known genetic lesions among Parkinson's disease patients. We have previously reported that in the Portuguese population the LRRK2 c.6055G > A; p.G2019S mutation has one of the highest frequencies in Europe.

Methods

Here, we follow up on those results, screening not only LRRK2, but also PRKN, SNCA and PINK1 in a cohort of early-onset and late-onset familial Portuguese Parkinson disease patients. This series comprises 66 patients selected from a consecutive series of 132 patients. This selection was made in order to include only early onset patients (age at onset below 50 years) or late-onset patients with a positive family history (at least one affected relative). All genes were sequenced bi-directionally, and, additionally, SNCA, PRKN and PINK1 were subjected to gene dosage analysis.

Results

We found mutations both in LRRK2 and PRKN, while the remaining genes yielded no mutations. Seven of the studied patients showed pathogenic mutations, in homozygosity or compound heterozygosity for PRKN, and heterozygosity for LRRK2.

Conclusion

Mutations are common in Portuguese patients with Parkinson's disease, and these results clearly have implications not only for the genetic diagnosis, but also for the genetic counseling of these patients.
Ovarian carcinomas with genetic and epigenetic BRCA1 loss have distinct molecular abnormalities
Authors: Press Joshua Z , De Luca Alessandro , Boyd Niki , Young Sean , Troussard Armelle , Ridge Yolanda , Kaurah Pardeep , Kalloger Steve E , Blood Katherine A , Smith Margaret , Spellman Paul T , Wang Yuker , Miller Dianne M , Horsman Doug , Faham Malek , Gilks C Blake , Gray Joe , Huntsman David G
Published: January 2008

Background

Subclassification of ovarian carcinomas can be used to guide treatment and determine prognosis. Germline and somatic mutations, loss of heterozygosity (LOH), and epigenetic events such as promoter hypermethylation can lead to decreased expression of BRCA1/2 in ovarian cancers. The mechanism of BRCA1/2 loss is a potential method of subclassifying high grade serous carcinomas.

Methods

A consecutive series of 49 ovarian cancers was assessed for mutations status of BRCA1 and BRCA2, LOH at the BRCA1 and BRCA2 loci, methylation of the BRCA1 promoter, BRCA1, BRCA2, PTEN, and PIK3CA transcript levels, PIK3CA gene copy number, and BRCA1, p21, p53, and WT-1 immunohistochemistry.

Results

Eighteen (37%) of the ovarian carcinomas had germline or somatic BRCA1 mutations, or epigenetic loss of BRCA1. All of these tumours were high-grade serous or undifferentiated type. None of the endometrioid (n = 5), clear cell (n = 4), or low grade serous (n = 2) carcinomas showed loss of BRCA1, whereas 47% of the 38 high-grade serous or undifferentiated carcinomas had loss of BRCA1. It was possible to distinguish high grade serous carcinomas with BRCA1 mutations from those with epigenetic BRCA1 loss: tumours with BRCA1 mutations typically had decreased PTEN mRNA levels while those with epigenetic loss of BRCA1 had copy number gain of PIK3CA. Overexpression of p53 with loss of p21 expression occurred significantly more frequently in high grade serous carcinomas with epigenetic loss of BRCA1, compared to high grade serous tumors without loss of BRCA1.

Conclusion

High grade serous carcinomas can be subclassified into three groups: BRCA1 loss (genetic), BRCA1 loss (epigenetic), and no BRCA1 loss. Tumors in these groups show distinct molecular alterations involving the PI3K/AKT and p53 pathways.
Nutritional therapies for mental disorders
Authors: Lakhan Shaheen E , Vieira Karen F
Published: January 2008

According to the Diagnostic and Statistical Manual of Mental Disorders, 4 out of the 10 leading causes of disability in the US and other developed countries are mental disorders. Major depression, bipolar disorder, schizophrenia, and obsessive compulsive disorder (OCD) are among the most common mental disorders that currently plague numerous countries and have varying incidence rates from 26 percent in America to 4 percent in China. Though some of this difference may be attributable to the manner in which individual healthcare providers diagnose mental disorders, this noticeable distribution can be also explained by studies which show that a lack of certain dietary nutrients contribute to the development of mental disorders. Notably, essential vitamins, minerals, and omega-3 fatty acids are often deficient in the general population in America and other developed countries; and are exceptionally deficient in patients suffering from mental disorders. Studies have shown that daily supplements of vital nutrients often effectively reduce patients' symptoms. Supplements that contain amino acids also reduce symptoms, because they are converted to neurotransmitters that alleviate depression and other mental disorders. Based on emerging scientific evidence, this form of nutritional supplement treatment may be appropriate for controlling major depression, bipolar disorder, schizophrenia and anxiety disorders, eating disorders, attention deficit disorder/attention deficit hyperactivity disorder (ADD/ADHD), addiction, and autism. The aim of this manuscript is to emphasize which dietary supplements can aid the treatment of the four most common mental disorders currently affecting America and other developed countries: major depression, bipolar disorder, schizophrenia, and obsessive compulsive disorder (OCD).

Most antidepressants and other prescription drugs cause severe side effects, which usually discourage patients from taking their medications. Such noncompliant patients who have mental disorders are at a higher risk for committing suicide or being institutionalized. One way for psychiatrists to overcome this noncompliance is to educate themselves about alternative or complementary nutritional treatments. Although in the cases of certain nutrients, further research needs to be done to determine the best recommended doses of most nutritional supplements, psychiatrists can recommend doses of dietary supplements based on previous and current efficacious studies and then adjust the doses based on the results obtained.
Proteome profiling of embryo chick retina
Authors: Mizukami Mina , Kanamoto Takashi , Souchelnytskyi Nazariy , Kiuchi Yoshiaki
Published: January 2008

Background

Little is known regarding the molecular pathways that underlie the process of retinal development. The purpose of this study was to identify proteins which may be involved in development of retina. We used a proteomics-based approach to identify proteins that are up- or down-regulated during the development of the embryo chick retina.

Results

Two-dimensional gel electrophoresis was performed with the retina of embryo chicken, which was obtained from embryos of day 7 (ED7) and of day 11 (ED11). The protein spots showing significant differences were selected for identification by MALDI mass spectrometry. Thirteen proteins were differentially expressed; seven proteins were up-regulated in embryo retina of chicken at ED 11 and six proteins were down-regulated. Significant proteins were also evaluated in embryo day 15 (ED15). Some of identified proteins were known to regulate cell proliferation, cell death, transport, metabolism, organization and extracellular matrix, and others also included novel proteins.

Conclusion

We identified thirteen proteins which differentially expressed in embryonal retina of chicken at day 7, as compared to the retina of embryo of day 11. They were various regulatory proteins for cellular signaling.
Protocol: Streamline cloning of genes into binary vectors in Agrobacterium via the Gateway® TOPO vector system
Authors: Xu Ruqiang , Qingshun Li Quinn
Published: January 2008

Background

In plant functional genomic studies, gene cloning into binary vectors for plant transformation is a routine procedure. Traditionally, gene cloning has relied on restriction enzyme digestion and ligation. In recent years, however, Gateway® cloning technology (Invitrogen Co.) has developed a fast and reliable alternative cloning methodology which uses a phage recombination strategy. While many Gateway- compatible vectors are available, we frequently encounter problems in which antibiotic resistance genes for bacterial selection are the same between recombinant vectors. Under these conditions, it is difficult, if not sometimes impossible, to use antibiotic resistance in selecting the desired transformants. We have, therefore, developed a practical procedure to solve this problem.

Results

An integrated protocol for cloning genes of interest from PCR to Agrobacterium transformants via the Gateway® System was developed. The protocol takes advantage of unique characteristics of the replication origins of plasmids used and eliminates the necessity for restriction enzyme digestion in plasmid selections.

Conclusion

The protocol presented here is a streamlined procedure for fast and reliable cloning of genes of interest from PCR to Agrobacterium via the Gateway® System. This protocol overcomes a key problem in which two recombinant vectors carry the same antibiotic selection marker. In addition, the protocol could be adapted for high-throughput applications.
Gene expression variation in African and European populations of Drosophila melanogaster
Authors: Hutter Stephan , Saminadin-Peter Sarah S , Stephan Wolfgang , Parsch John
Published: January 2008

Background

Differences in levels of gene expression among individuals are an important source of phenotypic variation within populations. Recent microarray studies have revealed that expression variation is abundant in many species, including Drosophila melanogaster. However, previous expression surveys in this species generally focused on a small number of laboratory strains established from derived populations. Thus, these studies were not ideal for population genetic analyses.

Results

We surveyed gene expression variation in adult males of 16 D. melanogaster strains from two natural populations, including an ancestral African population and a derived European population. Levels of expression polymorphism were nearly equal in the two populations, but a higher number of differences was detected when comparing strains between populations. Expression variation was greatest for genes associated with few molecular functions or biological processes, as well as those expressed predominantly in males. Our analysis also identified genes that differed in expression level between the European and African populations, which may be candidates for adaptive regulatory evolution. Genes involved in flight musculature and fatty acid metabolism were over-represented in the list of candidates.

Conclusion

Overall, stabilizing selection appears to be the major force governing gene expression variation within populations. However, positive selection may be responsible for much of the between-population expression divergence. The nature of the genes identified to differ in expression between populations may reveal which traits were important for local adaptation to the European and African environments.
Ostiolitholapaxy
Authors: Farkas Antal , Lőrincz László , Berczi Csaba , Varga Attila , Tóth Csaba
Published: January 2008

A szerzők nefroszkóp és ablakos kőfogó segítségével új, minimálisan invazív eljárást dolgoztak ki a juxtavesicalis uréterszakaszban elakadt kövek eltávolítására. Módszerüket ostiolitholapaxiának nevezték el. A dolgozatban ismertetik a beavatkozás részleteit és elért eredményeiket. – 1995. 1. 1. és 2006. 12. 31. között 48 ostiolitholapaxiát végeztek. 41 esetben sikeres kőeltávolítás történt, 7 esetben pedig ureteroscopiára került sor. A szerzők a 41 sikeres esetüket dolgozzák fel, részletesen ismertetve a műtéti technikát. A röntgenpozitív kövek átlagos nagysága 5,2 (3–12) mm volt. A férfi és nőbetegek aránya: 23/18. 19 beteget helyi, 22 beteget gerinc közeli érzéstelenítésben operáltak. A helyi érzéstelenítésben operált betegek közül 13 nő (68,4%), 6 (31,6%) pedig férfi beteg volt. A műtét átlagos időtartama 8,5 (3,5–35) perc, az átlagos utánkövetési idő pedig 95,3 (2–143) hónap volt. – A beavatkozás 85,41%-ban volt sikeres. Intraoperatív szövődmény nem fordult elő. Az utánkövetés során passzázszavart okozó uréterszűkület, illetve vesicoureteralis reflux kialakulását nem tapasztalták. – Tekintve a módszer egyszerűségét, hatékonyságát, valamint azt, hogy lokális anesztéziában is elvégezhető, és nem igényel bonyolult műszerezettséget, a módszer valamennyi kisebb méretű, röntgenpozitív, szájadékközeli, panaszokat és/vagy passzázsakadályt okozó kő esetében alkalmazható.
Geochemical and Geostatistical Investigations of Chromium Pollution in Groundwater
Authors: Siddique A. , Zaigham N. A. , Mallick K. A. , Mumtaz M. , Saied S.
Published: January 2008

Geochemical and geostatistical study of the chromium concentration in groundwater occurring at variable depths of 12 to 33.5 m (40 to 110 ft) in the Karachi urban area of Pakistan have been made. Samples were collected at variable distances, with a maximum of 1 km interval, on the bases of population, industries, types, and density. The chromium concentration has also been worked out to deduce the threshold value of the area under study and the estimation of probability impact modeling, in terms of concentration variation, by using the disjunctive kriging technique. The outcome of the present work appears to be a good tool to decipher pollution variation in the groundwater of highly urbanized areas, with respect to the population and industries. The patterns of distribution of chromium concentration in groundwater and pollution hotspots in particular localities appear to be more related to the types of industries than to the effect of population types.
Oxidation of Industrial Dyeing Wastewater by Supercritical Water Oxidation in Transpiring‐Wall Reactor
Authors: Gong Wei‐Jin , Li Fang , Xi Dan‐Li
Published: January 2008

Industrial dyeing wastewater was oxidized in supercritical water in a transpiring‐wall reactor, using hydrogen peroxide as an oxidant. Experiments were performed at 595 to 704 K and 18 to 30 MPa, with an oxidant dosage ratio ranging from 0.6 to 2.0. A chemical oxygen demand (COD) removal of more than 98.4% was achieved at 704 K and 28 MPa, with a retention time less than 35 seconds, which increased with the temperature, pressure, and oxidant. A modified first‐order rate expression was regressed from experimental data, taking into account the influence of induction time. The resulting pre‐exponential factor, A, and activation energy, Ea, were 1.07 seconds −1 and 12.12 kJ · mol −1, respectively, while the reaction order for feed wastewater (based on COD) and oxidant were assumed to be 1 and 0, respectively. Gas chromatography/mass spectrometry analysis for effluents indicated that carbon dioxide, carbon monoxide, and nitrogen were the main reaction products, and phenol; benzenecarboxylic acid; 1, 2‐benzenedicarboxylic acid; and isoquinoline were detected as intermediates.
Adsorption of Zinc Contained in the Poultry Feedstuff onto Clinoptilolite
Authors: Šucman E. , Páč J. , Brzosková K. , Vávrová M. , Kettisch P.
Published: January 2008

The aim of this work was to find whether an adsorbent used as an additive in the feed mixtures could influence the concentration of free available zinc. The feed supplement ZeoFeed, which often constitutes a part of animal feed mixtures, mainly for poultry, was used as adsorbent in the amount of 10 g kg-1 of the feed mixture. A substantial part of ZeoFeed is clinoptilolite, a natural form of zeolite. Two sample preparation methods were used for the determination of zinc. The microwave-assisted wet digestion method was used to achieve a complete decomposition of the feed mixture in order to determine the total zinc concentration. The extraction method represented a simplified model of the processes in the digestive fluid tract. The extraction was done under laboratory temperature for 30, 60 and 120 min. Concentrations of zinc both in digests and extracts were determined by the method of the differential pulse anodic stripping voltammetry. The total zinc concentration (mean ± 95% confidence interval) in the feed mixture without addition of clinoptilolite was found to be 145 ± 32.0 mg kg-1 and in the feed mixture with added clinoptilolite 146 ± 11.5 mg kg-1. The concentrations of free available zinc were approximately ten times lesser than the total amount. The analysis of extracts showed that no statistically significant differences between concentrations of zinc in extracts without clinoptilolite and with clinoptilolite addition have been found. The extraction time did not affect the extracted amount of zinc significantly. In addition to zinc, also other three trace elements, namely the essential trace element copper and the toxic trace elements cadmium and lead, were measured. However, these data have only preliminary value and need further verification.
Fatty Acid Composition in Intramuscular Lipids of Experimental Scaly Crossbreds in 3-Year-Old Common Carp (Cyprinus carpio L.)
Authors: Buchtová H. , Svobodová Z. , Křížek M. , Vácha F. , Kocour M. , Velíšek J.
Published: January 2008

The aim of the study was to determine the differences in the composition of fatty acids (in % of total fatty acids investigated), their total contents and ratios (n-6/n-3) in intramuscular lipids (IML) of three experimental scaly groups of carp (pure line PS: Přerov scaly carp, hybrid PS × M72: Přerov scaly carp × Northern mirror carp, hybrid PS × ROP: Přerov scaly carp × Ropsha scaly carp) in comparison with the mirror carp control group (hybrid M2 × M72: Hungarian mirror carp × Northern mirror carp). Compared with the controls (M2 × M72), fat content in meat of experimental groups of carp (PS, PS × M72, PS × ROP) was practically the same (p > 0.05). The highest fat content (89.8 ± 1.94 g kg-1) was found in meat of PS × ROP hybrids. Composition of fatty acids in IML was not influenced to any large degree by a hybrid type or by gender. The only exception was the IML of PS × ROP hybrids which, compared with controls (M2 × M72) and PS × M72 hybrids, contained significantly (p < 0.05) more polyunsaturated fatty acids (PUFAsum). Higher content of oleic acid (PS × ROP: 54.94 ± 0.70%) in carp fat was manifested by higher monounsaturated fatty acids (MUFAsum) values (PS × ROP: 64.20 ± 0.57%). IML of PS × ROP hybrids contained 6.99 ± 0.20% of linoleic acid and 0.53 ± 0.02% of arachidonic acid. Contents of α-linoleic acid (PS × ROP: 0.86 ± 0.09%), eicosapentaenoic acid (EPA) (PS × ROP: 0.69 ± 0.09%) and docosahexaenoic acid (DHA) (PS × ROP: 0.35 ± 0.02%) were low and influenced the PUFA n-6/n-3 ratio (PS × ROP: 3.25 ± 0.18). From this point of view, the IML of carp groups in this experiment constituted a relatively minor source of PUFAn-3 (PS × ROP: 2.39 ± 0.09%).
Modeling Freeway Diverging Behavior on Deceleration Lanes
Authors: El-Basha Ramy H. Soliman , Hassan Yasser , Sayed Tarek A.
Published: January 2008

Typically, deceleration speed-change lanes (SCLs) and exit ramp terminals on freeways are designed to allow vehicles to depart the freeway safely and efficiently. Freeway diverge areas with adequate SCL lengths should enable the exiting drivers to diverge off the freeway through traffic, decelerate to the desired ramp speed, and exit the freeway safely and comfortably. Safety problems can be expected if drivers are forced to reduce speed on the main traffic lanes or to decelerate at a very high rate. In Canada and the United States, the current design guides suggest that operation and safety could be enhanced on freeway SCLs by increasing their length. In this study, driver speed behavior at freeway diverge areas was examined by using data collected on 13 exit ramp terminals on Highway 417 in the city of Ottawa, Canada. The speed, geometric, and traffic data were collected and employed to model 85th percentile speeds and deceleration rates using linear regression analysis. The modeling attempts integrated in this study resulted in eight statistically significant predictive models at the 5% level of significance.
Evaluation of Impacts of Open Road Tolling on Main-Line Toll Plaza
Authors: Klodzinski Jack , Gordin Eric , Al-Deek Haitham M.
Published: January 2008

Implementation of open road tolling (ORT) can provide better performance for a toll collection facility than the use of a conventional toll plaza design. Improvements have been sought to decrease toll transaction times so that drivers experience reduced delays or none at all. Although intelligent transportation systems technology such as automatic vehicle identification in the form of electronic toll collection (ETC) is a concept that has revolutionized toll collection, with the ever-increasing traffic volumes on toll facilities, more innovative methods such as ORT are being deployed. Agencies around the world have implemented ORT, and some have integrated express (high-speed) ETC lanes in their normal plaza design. A main-line toll plaza in Orlando, Florida, was renovated following an ORT design concept. The plaza was expanded to include express ETC lanes separated from the cash payment lanes by a barrier. Data were collected before construction, during construction, and after construction was completed. Analysis showed that average reduced delays for manual cash customers equaled 49.8% and for automatic coin machine customers, 55.3%; and the speed in the express ETC lanes increased by 57%. To evaluate the benefits further, forecast scenario results from a toll plaza microsimulation model, TPSIM, were analyzed with positive conclusions. An analysis of crash data showed a 22% drop in total crashes at the plaza and a 26% drop in the plaza's area of influence. This case study provided conclusive results that implementing ORT compared with using a conventional toll facility is beneficial for improving toll collection.
Freeway Bottleneck Simulation, Implementation, and Evaluation
Authors: Halkias B. , Kopelias P. , Papandreou K. , Politou A. , Prevedouros P. , Skabardonis A.
Published: January 2008

A fully documented case of problem identification, simulation, implementation, and evaluation has been developed for freeway bottleneck congestion mitigation. The benefits of using simulation for assessing improvement scenarios of a congestion-generating merge between two freeways and an on-ramp in the central part of Attica Tollway in Athens, Greece, are presented. The best feasible alternative identified by two simulation programs, Integration and VisSim, was constructed, and before and after field and simulation results are available. Only 16 months passed between the initial data collection for bottleneck analysis and the 2 months of evaluation with the constructed improvement, thereby minimizing large temporal and other exogenous factors. As a result of conservative simulation assumptions, larger than forecast improvements in speed, travel times, and queue reduction were realized. The two simulators, however, provided reasonable and comparable measures of performance, which were instrumental in the decision to construct the proposed improvement.
Probabilistic Data-Driven Approach for Real-Time Screening of Freeway Traffic Data
Authors: Ishak Sherif , Kondagari Shourie , Alecsandru Ciprian
Published: January 2008

Freeway traffic surveillance systems currently collect large amounts of traffic data, sometimes a few gigabytes per day, to support various critical traffic management center functions such as incident detection, travel time and delay estimation, and congestion management. Reliable traffic information, however, requires applying quality control measures to the collected traffic data before archiving, dissemination to the public, or use in relevant applications. This paper presents a probabilistic data-driven methodology for real-time screening of freeway loop detector data. Two complementary approaches were developed to detect abrupt temporal changes in the traffic parameters, as well as possible inconsistencies among each pair of the three traffic parameters. A real-time data screening algorithm was devised to operate in three steps. An illustrative example is presented to explain how the algorithm can be applied to real-time data screening and how observations can be diagnosed for the most likely erroneous parameters.
High-Occupancy Vehicle Lanes and Hybrid Vehicles
Authors: Turnbull Katherine F.
Published: January 2008

This paper describes the use of high-occupancy vehicle (HOV) lanes by inherently low-emission vehicles (ILEVs) and hybrid vehicles. On the basis of the provisions of the Transportation Equity Act for the 21st Century, at least 10 states approved legislation allowing ILEVs to use HOV lanes without meeting the vehicle-occupancy requirements. The Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (SAFETEA-LU) allows states also to exempt qualifying hybrid vehicles from vehicle-occupancy requirements. Since the passage of SAFETEA-LU, FHWA has granted conditional approvals to Arizona, California, and New York for hybrid use of some or all HOV lanes in those states. Contrary to federal legislation, hybrid vehicles have been allowed to access HOV lanes in Virginia since 2000. As described in this paper, few ILEVs are in operation, and thus use of HOV lanes by ILEVs is minimal. On the basis of the experience in Virginia, California, and New York, however, owners of hybrid vehicles are using HOV lanes in those states.
Simulation Analysis of Truck-Restricted and High-Occupancy Vehicle Lanes
Authors: Siuhi Saidi , Mussa Renatus
Published: January 2008

Numerous studies have reported the efficacy of high-occupancy vehicle (HOV) lane restriction and truck lane restriction implemented independently, but the simultaneous use of both restrictions on an urban freeway corridor raises numerous operational and safety issues. This research study analyzed the operational and safety experience of an 83-mi corridor of I-95 in South Florida that has both HOV and truck lane restriction. Results of a field-validated VisSim simulation model showed that high-occupancy vehicles and automobiles gained significantly more travel time savings and speeds on the restricted lanes than on the general lanes. Also, vehicle queue lengths around critical merging and diverging areas increased significantly as the percentage of trucks increased. Results indicated that during peak traffic conditions right lanes had higher lane occupancy than left lanes, whereas during off-peak traffic conditions center lanes carried more vehicles per lane than the outermost lanes; these results suggest that congestion on right lanes forces automobiles to use left lanes. Furthermore, results showed that most lane changes occurred during peak traffic flow conditions—about twice that of off peak—and appreciable speed differences existed between restricted and nonrestricted lanes. Simulation results for off-peak traffic conditions did not show any noticeable changes in traffic operating characteristics resulting from lane restriction strategies. On the basis of these results, it can be fairly concluded that on urban freeways significant operational and safety benefits of the combined implementation of HOV and truck lane restrictions accrue during congested traffic conditions rather than during uncongested conditions.
Implementing the Concept of Reliability for Highway Capacity Analysis
Authors: Brilon Werner , Geistefeldt Justin , Zurlinden Hendrik
Published: January 2008

A stochastic concept for highway capacity analysis is presented. The capacity of a highway facility is regarded as a random variable instead of a constant value. Thus, the stochastic approach provides new measures of traffic flow performance based on aspects of traffic reliability. A method for the estimation of capacity distribution functions from empirical data based on statistical methods for lifetime data analysis is introduced. This method is derived for the analysis of freeway capacity. However, the stochastic approach also is shown to be applicable to intersections. Results of the analysis of data samples from freeway sections in Germany indicate that freeway capacity is Weibull-distributed with a considerable variance. A Monte Carlo technique based on the stochastic description of capacity is proposed to quantify freeway traffic performance over a whole year. This technique also provides a quantitative assessment for oversaturated conditions.
Headway Acceptance Characteristics of U-Turning Vehicles at Unsignalized Intersections
Authors: Liu Pan , Wang Xu , Lu Jian , Sokolow Gary
Published: January 2008

During the past two decades, more and more state departments of transportation have installed nontraversable medians and directional median openings on multilane highways. These installations have resulted in an increased number of U-turning vehicles at unsignalized intersections on multilane highways. The headway acceptance characteristics of U-turning vehicles are analyzed at unsignalized intersections on four-lane divided roadways. The critical headway for U-turn movement is estimated by using the maximum likelihood method. A binary logit model is developed to identify the influence of median width on the headway acceptance characteristics of U-turning vehicles. Results of this binary logit model indicate that the median width at a median opening significantly affects the decisions of U-turning drivers about accepting or rejecting a particular headway in the major-street traffic stream. Results of the maximum likelihood estimation indicate that a vehicle making a U-turn at an unsignalized intersection with a wide (=21 ft) median has a smaller critical headway than one making a U-turn at an unsignalized intersection with a narrow (<21 ft) median. The critical headway for U-turn movement at unsignalized intersections is about 6.4 s with wide medians and about 6.9 s with narrow medians. These estimated critical headways supplement the current capacity estimation method for unsignalized intersections and can be directly used in Harders' model to estimate the capacity of U-turn movement at unsignalized intersections.
Preliminary Evaluation of Metro Orange Line Bus Rapid Transit Project
Authors: Callaghan Lisa , Vincent William
Published: January 2008

This paper provides a preliminary assessment of the Metro Orange Line of Los Angeles County, California, one of the first full-feature bus rapid transit (BRT) systems in the United States. The paper also compares the Orange Line with two recent transit investments in Los Angeles: the Gold Line light rail and Metro Rapid, a rapid bus service with limited BRT features. The assessment is based on existing performance, cost, and operational data from the Orange Line's first year of service. The study found that the Orange Line is exceeding ridership projections, reducing travel times, easing congestion, and attracting people out of their cars. It is performing better than the Gold Line, which cost significantly more, yet carries fewer riders. Metro Rapid appears to have some cost-effectiveness advantages but lacks travel time consistency and a premium transit service image. The Orange Line also offers lessons for future BRT planners. The Orange Line has suffered several collisions between buses and private vehicles, primarily because private vehicles were running red lights. Safety changes included reducing bus speeds through intersections, which contributed to higher-than-projected travel times. If safety issues were addressed, this would provide valuable lessons for future at-grade busway projects. Also, as with some other recent projects, the Orange Line has pavement integrity issues. Further research would be useful in this area. Overall, the Orange Line is providing mobility benefits and attracting new riders to an extent usually thought possible only with expensive rail systems. As the Orange Line matures, further performance analysis and evaluation of land development impacts would be valuable.
Applicability of TransMilenio Bus Rapid Transit System of Bogotá, Colombia, to the United States
Authors: Cain Alasdair , Darido Georges , Baltes Michael R. , Rodriguez Pilar , Barrios Johan C.
Published: January 2008

The TransMilenio of Bogotá, Colombia, is the highest-capacity bus rapid transit (BRT) system in the world and one of the best examples of a high-level BRT system. It demonstrates what BRT can achieve if high-capacity design features and operating characteristics are provided. This paper highlights the different capabilities of BRT as demonstrated by the TransMilenio and assesses the extent to which these capabilities are applicable to BRT operations in the United States. A series of observations is made in relation to the topics of passenger capacity, capital cost-effectiveness, achievement of modal shift objectives, urban renewal, business and institutional models, and politics. The paper concludes by discussing the various issues related to the replication of the Bogotá model in the United States. Perhaps the central lesson to be learned from Bogotá is that BRT is capable of playing a role in the achievement of much wider objectives, such as sustainable mobility and urban renewal, when implemented as part of a holistic package of integrated strategies. Committing to the provision of a network of BRT routes gives the city the opportunity to magnify the mobility and urban renewal benefits from corridor level to the citywide level. The relatively low capital costs that have made this possible, within a relatively short time frame, should also be of interest to U.S. cities.
Service Reliability and Optimal Running Time Schedules
Authors: Furth Peter G. , Muller Theo H. J.
Published: January 2008

To improve reliability, transit routes have time points at which early vehicles are held. Holding reduces waiting time and the amount of time passengers have to budget for a trip. However, it also reduces operating speed and thus increases passenger riding time and, potentially, operating cost. A new approach is presented for quantifying the user costs associated with unreliability. User cost has three components: excess waiting time, potential travel time or buffer time (related to budgeted travel time), and mean riding time, of which the first two are reliability impacts. For long headway service, these costs can be determined from 2-percentile departure times, 95-percentile arrival times, and mean arrival and departure times at stops. With a simple route operations model on a hypothetical route, impacts of scheduling with different numbers of time points and with different levels of running time and cycle time supplements are explored, and optimal running time schedules are determined. For a typical case, the optimal time point schedule offers net benefits equivalent to 4.5 min of riding time per passenger compared with operation without time point control. Optimal route running times are roughly mean plus one standard deviation of uncontrolled running time, and optimal cycle time is roughly mean plus two to three standard deviations of uncontrolled route running time. Surprisingly, it was found that in an optimal schedule, inserting slack at time points does not increase cycle time, because slack time inserted en route simply substitutes for slack time needed in layover.
Stop Spacing Analysis Using Geographic Information System Tools with Parcel and Street Network Data
Authors: Furth Peter G. , Mekuria Maaza C. , SanClemente Joseph L.
Published: January 2008

Geographic databases and computing tools present an opportunity for improved analysis of bus stop location or spacing changes. Changes in stop location affect walking, riding, and operating cost; of these, the impact on walking is the most important and complex. Traditional models and design rules for stop spacing do not model the impact on walking precisely, because they assume uniform demand density and unobstructed walking paths. This paper discusses an analysis procedure based on a parcel-level geographic database (supplied by a local government body such as the city tax assessor) and a street network. Walking paths and stop service area boundaries are based on shortest path and Voronoi diagram methods applied to the street network. Data on each parcel's land use and development intensity are used to distribute historic on–off counts and thus estimate the demand arising in each parcel. For alternative stop sets, then, the demand at each stop, walking distance, riding time, and operating cost impacts can be determined. Case studies on transit routes in Boston, Massachusetts, and Albany, New York, demonstrate the method's practicality. Results confirm the benefits of a recent stop rationalization effort in Boston and show how proposed stop elimination and relocation plans can be adjusted to yield a greater net benefit to society.
Association of the cannabinoid receptor gene (CNR1) with ADHD and post‐traumatic stress disorder
Authors: Lu Ake T. , Ogdie Matthew N. , Järvelin Marjo‐Ritta , Moilanen Irma K. , Loo Sandra K. , McCracken James T. , McGough James J. , Yang May H. , Peltonen Leena , Nelson Stanley F. , Cantor Rita M. , Smalley Susan L.
Published: January 2008

Attention deficit hyperactivity disorder (ADHD) is a highly heritable disorder affecting some 5–10% of children and 4–5% of adults. The cannabinoid receptor gene (CNR1) is a positional candidate gene due to its location near an identified ADHD linkage peak on chromosome 6, its role in stress and dopamine regulation, its association with other psychiatric disorders that co‐occur with ADHD, and its function in learning and memory. We tested SNP variants at the CNR1 gene in two independent samples—an unselected adolescent sample from Northern Finland, and a family‐based sample of trios (an ADHD child and their parents). In addition to using the trios for association study, the parents (with and without ADHD) were used as an additional case/control sample of adults for association tests. ADHD and its co‐morbid psychiatric disorders were examined. A significant association was detected for a SNP haplotype (C‐G) with ADHD (P = 0.008). A sex by genotype interaction was observed as well with this haplotype posing a greater risk in males than females. An association of an alternative SNP haplotype in this gene was found for post‐traumatic stress disorder (PTSD) (P = 0.04 for C‐A, and P = 0.01 for C‐G). These observations require replication, however, they suggest that the CNR1 gene may be a risk factor for ADHD and possibly PTSD, and that this gene warrants further investigation for a role in neuropsychiatric disorders. © 2008 Wiley‐Liss, Inc.
Dye behavior of cationically treated silk
Authors: Xiang Wei , Cai Zai‐Sheng
Published: January 2008

To increase the performance of silk fabrics, especially their dyeability, a cationic modifying agent, 3‐(trimethoxysilyl) propyl dodecyl dimethyl ammonium chloride (HSQA), was prepared in our laboratory. The dye behavior of the cationized silk was examined with five leveling‐type acid dyes. Better color shades and good washing fastness were achieved after silk was cationized by HSQA, and it was possible to dye silk under neutral conditions at 70°C. The equilibrium adsorption isotherm and kinetic properties of the cationized silk dyed with CI Acid Orange 7 were investigated. The adsorption of CI Acid Orange 7 onto the HSQA‐cationized silk was also in good agreement with the Langmuir isotherm, with an enthalpy and an entropy of −20.13 kJ/mol and −30.06 J/mol K respectively. A pseudo‐second‐order kinetic model agreed well with the dynamic behaviors for the adsorption of CI Acid Orange 7 onto the cationized silk under neutral conditions, with the activation energy decreasing from 61.87 to 53.32 kJ/mol. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Mechanical properties of polybenzoxazine syntactic foams
Authors: Santhosh Kumar K. S. , Reghunadhan Nair C. P. , Ninan K. N.
Published: January 2008

Syntactic foams of polybenzoxazine, containing moderately high volume percentage of glass microballoons, were prepared. The specific gravity decreased with increase in microballoon content. The disproportionate decrease in specific gravity was ascribed to entrapment of air voids during compaction. The high content of microballoon increased the possibility for air voids that tended to get accumulated. The effect of microballoon concentration on tensile, compressive, and flexural strengths of the foams was studied. Tensile and compressive properties were optimized at about 68% by volume of microballoon while flexural strength decreased marginally on increasing the microballoon content. Althought the specific tensile and compressive strength showed a maximum followed by a decrease, the specific flexural strength systematically increased with microballoon content. The increased packing density of syntactic foam of a given constituent composition increased the compressive strength. The property variation was corroborated by morphological features, as evidenced in scanning electron micrographs. The syntactic foams showed “multiple resin‐neck formation” and “disc‐shaped microballoon regions.” The crushing of microballoons during molding was inevitable when compaction was effected to achieve a density beyond the theoretical one. Low‐density syntactic foams tend to fail at lower loads because of fracturing of microballoons. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Hybrid Ligands with N‐Heterocyclic Carbene and Chiral Phosphaferrocene Components
Authors: Willms Holger , Frank Walter , Ganter Christian
Published: January 2008

N‐Heterocyclic carbenes (NHCs) possessing one or two 3,4‐dimethylphosphaferrocenyl substituents and either methylene or ethylene alkyl bridges have been prepared. These carbenes turned out to be remarkably stable and were characterized by NMR methods and partly by mass spectrometry. Their molybdenum and ruthenium complexes were examined in order to determine the electronic properties and the coordination behaviour of these chiral PC‐ and PCP‐chelate ligands, which combine a NHC unit as a strong σ‐donor with π‐accepting phosphaferrocene moieties. Crystal structures of one ligand precursor and of three complexes have been determined.
Risk of hypothyroidism in older breast cancer patients treated with radiation
Authors: Smith Grace L. , Smith Benjamin D. , Giordano Sharon H. , Shih Ya Chen T. , Woodward Wendy A. , Strom Eric A. , Perkins George H. , Tereffe Welela , Yu Tse Kuan , Buchholz Thomas A.
Published: January 2008

BACKGROUND.

Hypothyroidism is a potential complication after radiation therapy (RT) when treatment fields include the thyroid. The authors assessed risk of hypothyroidism in breast cancer patients who were receiving RT to a supraclavicular field, which typically includes a portion of thyroid.

METHODS.

The authors identified 38,255 women (aged >65) without history of hypothyroidism from the Surveillance, Epidemiology, and End Results (SEER)‐Medicare cohort diagnosed with stage 0‐III breast cancer from 1992–2002 and 111,944 cancer‐free controls. The authors compared hypothyroidism incidence among irradiated patients with 4 + positive lymph nodes (4 + LN, surrogate for supraclavicular RT) and no positive nodes (0 LN, surrogate for no supraclavicular RT), nonirradiated patients, and controls. Proportional hazards models tested associations of LN, RT, and breast cancer status with hypothyroidism.

RESULTS.

The 5‐year incidence of hypothyroidism was identical (14%) in irradiated patients with 4 + LN, 0 LN, and nonirradiated patients (P = .52). After adjusting for sociodemographic and clinical characteristics, hypothyroidism risk was not increased in irradiated patients with 4 + LN versus 0 LN (hazard ratio(HR) = 1.04; 95% confidence interval (CI), 0.89–1.23). However, all patients, regardless of RT status, were more likely to be diagnosed with hypothyroidism compared with cancer‐free controls (HR = 1.21; 95% CI, 1.17–1.25).

CONCLUSIONS.

Development of hypothyroidism is fairly common in older breast cancer survivors. Although supraclavicular irradiation does not appear to amplify risks, further studies on the role of routine thyroid function monitoring in all breast cancer patients regardless of treatment status may be warranted, given the excess risks compared with the general population. Cancer 2008. ©2008 American Cancer Society.