bluuebunny/crossref_metadata_2025 huggingface dataset:
Prevalence of various types of allergens in ocular allergic conditions of patients from Pokhara, Nepal
Authors: Shrestha Sachet Prabhat , Pokhrel Amod K , Malla Pushpa , Godar Srijana Thapa
Published: July 2014

Introduction: Ocular allergic conditions are mostly recurrent and the drugs prescribed, especially corticosteroids, have serious side effects. Therefore, when maximal tolerated topical and systemic medications are unable to control allergic conjunctivitis, a skin prick test for allergens should be conducted and patients should be taught to avoid these allergens. Objective: To find out the prevalence of common allergens inciting ocular allergic diseases in Nepal. Subjects and methods: A total of 13,376 skin prick tests were performed on 76 patients suffering from different chronic recurrent ocular allergic conjunctivitis with 176 common allergens (pollens, fungi, insects, dusts, danders, fabrics/ feathers, food, parthenium leaves, tobacco and mite). Buffer saline was used as a negative control while histamine acid phosphate was used as a positive control. Grading of the skin prick test reaction was done by comparison to the histamine positive control. Only markedly positive reactions were considered positive. Relevant data were entered into the excel spreadsheet and analyzed with the Stata-12 commercial package. The association between allergic conditions and socio-demographic, environmental and other co-variates were tested by the chi-square test. Results: The common offenders found in the study were mite (42.11 %) followed by fabrics/ feathers (20.39 %), dusts (18.18 %), pollen (17.05 %), non-juicy food (15.02 %), dander (13.60 %), juicy food (11.64 %) and fungus (9.87 %), and tobacco (6.58 %), parthenium leaves (5.26 %) and insects (3.17 %) were less common offenders. Conclusions: All ocular allergy patients should undergo skin prick tests to find out the allergens causing their allergy and then receive specific immunological treatment (SIT). DOI: http://dx.doi.org/10.3126/nepjoph.v6i1.10759 Nepal J Ophthalmol 2014; 6 (2): 6-23
Prevalence, risk factors and awareness of diabetic retinopathy among admitted diabetic patients at a tertiary level hospital in Kathmandu
Authors: Thapa Raba , Joshi Deepak Man , Rizyal Aparna , Maharjan Nhukesh , Joshi Rajesh Dhoj
Published: July 2014

Introduction: Diabetic retinopathy (DR) is one of the commonest causes of visual impairment and blindness in Nepal. Objectives: The study aims to explore the prevalence, risk factors and awareness of DR among admitted diabetic patients. Materials and methods: A non-interventional case series study was conducted among the inpatient diabetic cases referred for ophthalmic consultation. The patients’ detailed demographics, awareness on DR, concurrent systemic problems, and glycemic control status were recorded. DR was graded using the Early Treatment Diabetic Retinopathy Study Criteria. Main outcome measures: The prevalence, risk factors and awareness of diabetic retinopathy among the study participants was analyzed. Results: A total of 277 diabetic patients were enrolled in the study. The mean age was 62.25 ± 13.26 years. Only one-third (34.6 %) of the cases were admitted for sugar control and newly diagnosed cases comprised of 19.49 %. Nearly half of the cases (46.6 %) were not aware of diabetic retinopathy and dilated fundus evaluation was done for the first time in 44.4 %. DR was found in 38.26 % of the cases and was diagnosed in 13 % of the new cases. Almost four-fifths (78 %) of the diabetics had had the disease for a duration of 16 to 20 years. Clinically significant macular edema was found in 5.78 % and proliferative DR in 2.52 %. DR was significantly associated with the duration of diabetes (P value = 0.001) and concurrent hypertension (P value = 0.004). Conclusion: The prevalence of DR was 38 % among the admitted diabetic cases and the DR was significantly associated with the duration of diabetes and systemic hypertension. Almost half of the cases had been unaware of DR before referral. This emphasizes the importance of the collaboration of the physician and the ophthalmologist for an early DR detection.   DOI: http://dx.doi.org/10.3126/nepjoph.v6i1.10760   Nepal J Ophthalmol 2014; 6 (2): 24-30
Prevalence of and associated risk factors for pterygium in the high altitude communities of Upper Mustang, Nepal
Authors: Maharjan IM , Shreshth E , Gurung B , Karmacharya S
Published: July 2014

Objective: To determine the prevalenceof and associated risk factors for pterygiumin the high altitude communities of the Upper Mustang region of Nepal, near the Tibet border. Materials and methods: Six villages of the Upper Mustang were selected based on the concentration of population. All subjects were permanent residents aged 16 years and older, and recruited through a household census with mobilization of local monks who had been trained as interviewers, and people were invited to attend the eye clinic for a complete examination. A cross-sectional studywas conducted which included the parameters oflaterality, severity, occupation, age, sex and altitude of residence. Results:The study population comprised 1,319 individuals of which 637 (48.29%) weremale and682 (51.71%) were female.The overall prevalence of pterygium, was 10.08% (133 of 1,319), with 42.86% for males and 57.14% for females. The mean age of the subjects was45.83 years and the mean SD 17.94. The majority of the subjects had a unilateral pterygium. The right eye(n=63) was predominately affected, in 57.80% of the total subjects. Farmers and construction workers, which comprised of 36.09% and 28.57% respectively, had a higher prevalence of pterygium. The most affected age group was the 66 to 75 years group (n=31: 23.31%). The prevalence increased linearly with age. The severe Grade III and Grade IV pterygium were predominant in the age group of 56-65 years, comprising 28.58% of all the cases;the less severe Grade I was also predominant in the same age group,with 23.56%, and Grade II (0-2 mm) was predominant in the age group of 46-55, with 31.03%. Conclusion: Pterygiumisa significant public health problem in the high altitude communities of Nepal. It is more prevalent amongst the farmers than in the other professionals. DOI: http://dx.doi.org/10.3126/nepjoph.v6i1.10774 Nepal J Ophthalmol 2014; 6 (2): 65-70
Post penetrating keratoplasty glaucoma – A review
Authors: Gupta P , Sharma A , Ichhpujani P
Published: July 2014

Glaucoma following penetrating keratoplasty remains a challenge for the treating ophthalmologist. Its frequent occurrence, difficult diagnosis and recalcitrant nature coupled with the propensity to cause irreversible visual loss makes it essential to identify the problem early and manage it effectively.A careful pre-operative assessment along with appropriate intra-operative measures can help to reduce the chances of developing glaucoma in the post-operative period. Wherever indicated, prompt therapy should be initiated to lower intraocular pressure and salvage vision. Effective management of post-operative keratoplasty glaucoma remains an enigma with no single therapy being suited for all cases. One has to weigh the risks and benefits of the anti-glaucoma drugs on the corneal graft. However, it should be kept in mind that although there is a potential option for a graft exchange, vision lost from glaucomatous optic nerve damage cannot be recovered.This review aims at highlighting the magnitude of the problem, assessing the risk factors that predispose to post-penetrating keratoplasty glaucoma along with the methodology for its diagnosis and management. DOI: http://dx.doi.org/10.3126/nepjoph.v6i1.10776 Nepal J Ophthalmol 2014; 6 (2): 80-90
Sub-conjunctival dislocation of posterior chamber intra-ocular lens: five years after manual, small-incision cataract surgery
Authors: Joshi Rajesh Subhash
Published: July 2014

Introduction: Ocular trauma can cause serious complications in eyes operated for cataract. Case: A 70-year- old lady had sustained blunt trauma to the left lower lid which resulted in a sub-conjunctival dislocation of the posterior chamber intraocular lens (PCIOL). The patient had undergone an uneventful manual, small-incision, sutureless cataract surgery with implantation of a PCIOL for senile cataract five years ago in the same eye. She had no ocular or systemic predisposing factors for wound dehiscence. Surgical exploration revealed a scleral rupture 7 mm in length, 2 mm behind the limbus at the 12’O clock position along the surgically-constructed wound. However, the scleral tunnel was not damaged. The PCIOL was removed. Wound closure was done to avoid infection of the intraocular structures. Her best-corrected visual acuity was 20/60 at the three months’ follow-up. Conclusion: Surgeons should be aware of such complications occurring due to trauma. We recommend suturing of the scleral wound to strengthen it in cases of a deep scleral groove or when there is a possibility of a premature entry of the wound into the anterior chamber. DOI: http://dx.doi.org/10.3126/nepjoph.v6i1.10777   Nepal J Ophthalmol 2014; 6 (2): 91-94
Spontaneous rupture of lens capsule with dislocation of nucleus in hypermature cataract
Authors: Malik VK , Jhalani Rishi , Malik KPS , Gupta Abhishek
Published: July 2014

We report a case of spontaneous rupture of the lens capsule in a woman with hypermature cataract, who presented to us with nucleus dislocation in the posterior chamber of her left eye. The capsule had ruptured inferiorly and the nucleus had slided out of it. The anterior chamber was quiet; and no sign of uveitis was noted. She underwent nucleus extraction and IOL implantation in the sulcus. Spontaneous rupture of the anterior lens capsule that leads to dislocation of the nucleus is a rare complication of hypermature cataracts. DOI: http://dx.doi.org/10.3126/nepjoph.v6i1.10778 Nepal J Ophthalmol 2014; 6 (2): 95-97
Intra-ocular lens opacification in the anterior chamber leading to loss of vision in an adolescent
Authors: Chaudhry Mrindu , Mundey Keerti , Baisakhiya Shikha , Sethi Sumita
Published: July 2014

Objective: To report a rare case of intraocular lens (ACIOL) opacification in the anterior chamber in an adolescent and to discuss the possible mechanism of its occurrence and the ways of its prevention. Case: A 16-year-old male underwent cataract surgery for developmental cataract with placement of a foldable posterior chamber IOL in the anterior chamber. There was subsequent opacification of the IOL, which was replaced by a scleral fixated posterior chamber intraocular lens. The post-operative visual acuity improved to 6/18. Conclusion: The posterior chamber IOL implanted in the anterior chamber can get opacified possibly due to postoperative intraocular inflammation. DOI: http://dx.doi.org/10.3126/nepjoph.v6i1.10780   Nepal J Ophthalmol 2014; 6 (2): 102-104
POEMS syndrome as an uncommon cause of papilledema
Authors: Franco Carlos Mario , Balparda Kepa , Díaz Ana María , Jiménez Daniel , Pamplona Ana Paulina
Published: July 2014

Background: Polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes (POEMS) syndrome is an uncommon condition related to a paraneoplastic syndrome secondary to an underlying plasma cell disorder. Among the myriad of manifestations of the disease, ocular signs and symptoms are relatively prevalent, affecting about half of all patients with the disease. Objective: To report the ocular manifestations of POEMS syndrome. Case: A 47-year-old lady diagnosed to have POEMS syndrome presented with painless progressive visual diminution. Her color vision was impaired. There was bilateral papilloedema. Conclusion: POEMS syndrome should be considered among the differential diagnoses of all patients with a bilateral papilledema in which no other cause can be readily elucidated. DOI: http://dx.doi.org/10.3126/nepjoph.v6i1.10781 Nepal J Ophthalmol 2014; 6 (2): 105-108
An overlap of Coats and Eales diseases or a Coats variant?
Authors: Kucukevcilioglu Murat , Sobaci Gungor , Durukan Ali Hakan , Erdurman Fazil Cuneyt , Ceylan Osman Melih
Published: July 2014

Objective: To report an association between Coats and Eales diseases, an uncommon presentation. Case: A 21-year-old male presented with gradual visual impairment of two years duration in his left eye. The slit-lamp examination of the affected eye revealed +2 vitreous cells. The other findings were peri-papillary fluid accumulation and extensive macular lipid exudate deposition. Small white vessels were coursing over the macula. The major veins were dilated and tortuous and massive sheathing of both arteries and veins was forming a common sheath. In the mid-periphery and periphery of the retina, discrete hard exudates, tiny superficial retinal hemorrhages and massive vascular sheathing were present. In the inferotemporal region, two intra-retinal macrocysts were located distal to the retinal vasculature. Fluorescein angiography (FA) of the left eye highlighted numerous aneurysmal dilatations throughout the posterior pole. Fluorescein angiography also showed para-foveal telangiectasia and tiny telangiectatic vessels on the optic disk that led to late staining of the macula and optic disk. Hyperfluorescent patches of deep choroiditis were present in the early phases. There was segmental but no diffuse staining of the retinal veins which showed massive sheathing on fundoscopy. In the periphery, segmental venous staining and choroidal leakage to a lesser extent were observed. In the infero-temporal quadrant, a clear-cut zone of non-perfusion and vascular abnormalities (micro-macro aneurysms, veno-venous shunts, venous beading) at the junction between the perfused and non-perfused zones were present. The findings were reminiscent of both Coats and Eales diseases. Conclusion: Though known as two distinct entities, both retinal pathologies may present in a single form. DOI: http://dx.doi.org/10.3126/nepjoph.v6i1.10782  Nepal J Ophthalmol 2014; 6 (2): 109-112
Ocular malignant melanoma – a report of two cases
Authors: Reddy SC , Darnal HK
Published: July 2014

Introduction: Melanoma is a rare malignant tumour in the eye. Objective: To report two cases of malignant melanoma in the eye, one in the conjunctiva and the other in the choroid. Cases: The first case was in a 49-year-old lady who presented with a swelling on the inner side of left upper eyelid. The vision was 6/6. On everting the eyelid, multiple, pigmented, nodular swellings were noted on the tarsal conjunctiva. Excision biopsy confirmed the diagnosis of malignant melanoma of the conjunctiva. A pigmented nodular swelling occurred on the lower bulbar conjunctiva in the same eye one-and-a-half years after the first presentation. There were no secondary nodules in the body. Excision biopsy confirmed malignant melanoma of the conjunctiva. The second case was in a 72-year-old lady who presented with pain and bleeding in the right eye. There was no perception of light. The cornea was hazy and the details behind it could not be seen. There was micro perforation of the cornea with oozing of blood and secondary glaucoma. B-scan ultrasonography of the right eye revealed an intraocular tumour. The histopathology of the enucleated eyeball confirmed the diagnosis of malignant melanoma of the choroid. Conclusion: In the case of conjunctival melanoma, the occurrence of tumour at multiple sites and absence of recurrence at the original site suggests the possibility of de novo origin of the tumour. Secondary glaucoma and bleeding may be the presenting features of melanoma in the choroid. DOI: http://dx.doi.org/10.3126/nepjoph.v6i1.10783  Nepal J Ophthalmol 2014; 6 (2): 113-118
Ocular myocysticercosis
Authors: Joob Beuy , Wiwanitkit Viroj
Published: July 2014

DOI: http://dx.doi.org/10.3126/nepjoph.v6i1.10788 Nepal J Ophthalmol 2014; 6 (2): 127
A Comedian on Tragedy: Colley Cibber’s Apology and The Rival Queans
Authors: Davis Vivian L.
Published: July 2014

While eighteenth-century actor and theatre manager Colley Cibber is most frequently discussed within the context of sentimental comedy, this article addresses the comedian’s writing for and about the tragic stage. The neoclassical establishment consistently argued for the propriety of tragedy; however, actor and manager Cibber in his 1740 autobiography makes a case for the ludic qualities of successful tragic performance which, he insists, produces pleasure not tied to moral improvement. Moreover, Cibber embraces, rather than bemoans, the destabilization of social hierarchies that attends confessed generic hybridity. In an analysis of the comic burlesque The Rival Queans, a parody of Nathaniel Lee’s earlier tragedy The Rival Queens, I show how Cibber’s tragic stage was less concerned with categories of masculinity and femininity than in the sheer fluidity of gender. Experimenting with gender and genre in light of the period’s changing notions of sexual difference, the comedian revalues mixed genres and gender confusion as a site of illicit pleasure, providing an affective yet ephemeral other against which tragedy’s formidable narratives about gender and nation took shape.
« Humour » et « Wit »: Faire l’histoire de deux mots dans l’Angleterre moderne (XVIIe–XVIIIe siècles)
Authors: Lavie François
Published: July 2014

RÉSUMÉ

Comment accéder aux différents sens d’un mot à l’époque moderne? Les dictionnaires demeurent la principale source en sémantique historique, mais leur intérêt décroît à mesure que l’on remonte dans le temps. La précision des définitions est fortement dépendante des progrès de la discipline et du sérieux des lexicographes. De plus, les dictionnaires permettent de dater l’enregistrement ou le dépôt d’une acception nouvelle, mais en aucun cas son apparition. Si l’on veut retracer l’évolution des mots « humour » et « wit » aux XVIIe et XVIIIe siècles, il faut compléter les sources lexicographiques par d’autres sources, celles où s’opère le processus de création de sens. Le mot « humour » a connu deux changements sémantiques fondamentaux: le premier à la fin du XVIe siècle, et le second entre la fin du XVIIe et le milieu du XVIIIe siècle. À l’issue de ce processus, le mot a acquis sa signification moderne sous la plume de Corbyn Morris (1710–79). Mon intention est triple: dater l’enregistrement des sens successifs des mots « humour » et « wit » grâce aux dictionnaires, localiser la source de ces évolutions sémantiques, et, enfin, étudier les rapports entre « humour » et « wit ».
Amphiphilic Choline Carboxylates as Demulsifiers of Water-in-Crude Oil Emulsions
Authors: Aburto Jorge , Márquez Daniel M. , Navarro Juan C. , Martínez-Palou Rafael
Published: July 2014

Water/oil emulsions are formed in oil wells due to the presence of natural surfactants. As water/oil phase separation is necessary before oil refining, demulsifiers are used to break water/oil emulsions. In this work, environmentally friendly ionic surface-active choline carboxylates were synthesized from anionic exchange involving choline chloride under microwave dielectric heating. Microwave irradiation was also employed as a fast method for following the kinetics of the demulsification process with the synthesized demulsifiers. Choline palmitate showed the best performance as demulsifier.
Synthesis and Antitumor and Surface Activity of Novel Tetrachloro Metallate Complexes of Sulfaquinoxaline with Co(II), Cu(II), or Sn(II) Chlorides
Authors: Saleh Nashwa , Khowdiary Manal , Badawi Abdel Fattah
Published: July 2014

New sulfonamide tetrachloro metallate complexes that might possess strong carbonic anhydrase (CA) inhibitory properties were synthesized by the reaction of 4-amino-N-(quinoxalin-2-yl) benzene sulfonamide (sulfaquinoxaline) hydrochloride with different metal chlorides, i.e. CoCl2, CuCl2 or SnCl2. The produced metal complexes of the sulfonamide derivative, containing divalent cations, were characterized by standard procedures. These metal complexes might possess topical antiglaucoma properties which might make them more effective as pharmacological agents. The synthesized complexes exhibited significant cytotoxic activity against colon HCT-116 human cell line. Surface properties of these surfactants were investigated. The surface properties studies included critical micelle concentration (CMC), maximum surface excess (Γmax), minimum surface area (Amin). Free energy of micellization (ΔG°mic) and adsorption (ΔG°ads) were calculated.
Adapting an Online Transit Journey Planner into a Low-Cost Travel Survey Tool
Authors: Schmitt Lorelei , Harris Sally , Currie Graham
Published: July 2014

Urban transport authorities worldwide face difficult trade-offs in collecting information on public transit users. The costs of data collection can be high, and the technical challenges in understanding complex travel patterns require substantive survey resources. However, rapid technology advances have yielded improved traveler information tools. The improved tools enable the encoding of complex travel requests in transit journey planners, which are now a common feature of transit passenger information websites (TPIWSs). This paper describes the experience of developing an online survey tool in the journey planner section of a TPIWS as a new mechanism to undertake research in an effective and inexpensive way. The approach integrates information collated from the journey planner outputs and explores passengers’ experiences of journeys made on the basis of online surveys. Journey planner outputs were first recorded along with the answers to two simple poll questions. Respondents were then invited to undertake a follow-up survey after they had completed the trips for which they had used the journey planner. A total of 3,537 polls were submitted, and 658 follow-up surveys were completed. The samples users were in general younger and had characteristics different from those of the general transit market. However, overall the tool proved to be a powerful, easy-to-use, and inexpensive means of collecting information about complex travel behaviors. The lessons learned are described, and approaches are suggested for how on-screen polling could be improved, including computing approaches to manage web pop-up blockers, which are thought to have reduced sample sizes and possibly affected the demographic composition achieved. Implications for industry practice and opportunities for future research in this area are identified.
Trip Purpose Identification from GPS Tracks
Authors: Montini Lara , Rieser-Schüssler Nadine , Horni Andreas , Axhausen Kay W.
Published: July 2014

Travel surveys are increasingly taking advantage of GPS data, which offer precise route and time observations and a potentially reduced response burden. In these surveys, travel diaries are usually constructed automatically where research on the employed procedures has been focused on mode identification. The goal of the research reported here was to improve trip purpose identification. The analysis used random forests, a machine-learning approach that had been successfully applied to mode identification. The analysis was based on GPS tracks and accelerometer data collected by 156 participants who took part in a 1-week travel survey in Switzerland that was completed in 2012. The results show that random forests provide robust trip purpose classification. For ensemble runs, the share of correct predictions was between 80% and 85%. Different setups of the classifier were possible and sometimes required by the application context. The training set and its input variables (feature set) of the classifier were defined in various ways. Four relevant setups were tested for this study.
Impact of Traffic Images on Route Choice and the Value of Time Estimates in Stated Preference Surveys
Authors: Harline Carl E. , Burris Mark W.
Published: July 2014

A difficult aspect of the use of stated preference (SP) experiments to predict travel behavior is the proper presentation of attributes and characteristics of hypothetical trips to respondents. With an increase in the number of transportation choices, the task of concisely and accurately communicating trip attributes in the SP setting becomes increasingly more important. Recent attempts to introduce innovative strategies into the SP setting have yielded techniques to summarize trip attributes more efficiently for respondents. One technique is to use images of traffic conditions as a supplemental means to summarize average trip speed, travel time reliability, and degree of congestion. However, little research has been performed to test the effects of the use of traffic images on models of route choice built from this kind of SP data. In this research, an SP setting was developed to measure the influence of images of traffic conditions on SP responses. Pictures of traffic conditions that correlated to average trip speed were either shown to or withheld from a survey population from Austin, Texas, depending on random assignment. A panel-effects, mixed, multinomial logit model was built to estimate the respondent's route choice behavior. Overall, the model parameters discovered no evidence to support the assertion that traffic image presentation had a statistically significant effect on route choice with respect to the value of travel time savings or the value of travel time reliability.
Evaluation of Two Methods for Identifying Trip Purpose in GPS-Based Household Travel Surveys
Authors: Oliveira Marcelo G. Simas , Vovsha Peter , Wolf Jean , Mitchell Michael
Published: July 2014

Data needs for developing travel demand models have increased at the same time that household travel survey (HTS) participation rates have generally fallen over recent decades. GPS-assisted HTS methods are recognized today as the most promising direction in further enhancement of individual travel data collection. The principal advantage of the GPS-assisted survey technology is that a full stream of locations visited by the person is identified with a high level of spatial and temporal resolution, but automatic identification of trip purpose remains an issue that is difficult to solve. This paper evaluates the performance of two methods, choice modeling and decision tree analysis, that can be used to build models capable of identifying trip purpose. The developed methods assume that basic household- and person-level data, typically collected in an HTS, are available, as are supporting spatial data sets. The methods presented are then evaluated for a case study that employed data from the 2011 Atlanta Regional Commission HTS. The developed models produced encouraging results with overall accuracy greater than 70% across all purposes and around 90% for mandatory activities (i.e., work and school). The performance of the developed models was evaluated in terms of error rates by purpose category and the impact of ancillary spatial data. The paper concludes with a summary of the findings and recommendations for practitioners.
Better Pen-and-Paper Surveys for Transportation Research in Developing Countries
Authors: Campbell Andrew A. , Cherry Christopher , Ryerson Megan , Jones Luke
Published: July 2014

In developing countries, the rapid pace of socioeconomic and technological change necessitates the use of quick-response survey methods. Transportation researchers often work with limited budgets in environments with relatively low rates of computer and Internet access. Such conditions can preclude the use of the computer-assisted survey methods that are preferred for conducting research in industrialized countries. This paper describes novel methods for low-cost and high-quality data collection in a data-poor environment. The context is a stated preference (SP) experiment to estimate adoption of bikeshare and electric bikeshare in Beijing, but the methods are transferable. Two main methodological contributions are described. The first is a unique survey design that allows SP pivoting to occur within a single pen-and-paper interview (PAPI). For small- to medium-sized surveys, this design is often more cost-effective than traditional pivoting methods that require either a multistage PAPI survey or computer-assisted interviews. The second contribution is the demonstration of the use of affordable GPS technologies and publicly available data for the purpose of survey protocol enforcement and quality control. The paper describes survey design features that are of particular value for nonmotorized or semimotorized transportation research.
Use of Subway Smart Card Transactions for the Discovery and Partial Correction of Travel Survey Bias
Authors: Spurr Tim , Chapleau Robert , Piché Daniel
Published: July 2014

Although the theoretical sources of bias in travel surveys have been documented, data that describe an entire population of travelers rarely permit the reliable detection and measurement of bias. The existence of large databases of smart card transactions in public transit systems presents an opportunity to do so. In this paper, a typical average weekday of travel demand data from the Montreal, Canada, household travel survey is confronted with a single, specific day of smart card transactions. The object of comparison is the Montreal subway system, which is involved in 10% of all daily trips within the metropolitan area. The results of the initial analysis indicate that although the survey accurately reproduces daily subway ridership, it overestimates subway boardings by 24% during peak periods. This overestimation can be corrected by adjusting the weights of home-based trips to match entry volumes at subway stations during the morning peak period. The results of the reweighting procedure suggested that francophone households that use transit had a greater propensity to respond to the survey compared with other households. Furthermore, even after reweighting, the travel survey underestimated off-peak demand by roughly 21%. The underestimation was likely attributable to underreporting of non–home-based trips by respondent households and nonresponse of specific population groups.
Establishing the Links between Online Activity and Car Use
Authors: Le Vine Scott , Latinopoulos Charilaos , Polak John
Published: July 2014

The links between online activity and physical mobility are of wide and growing interest to researchers, practitioners, and policy makers. This paper presents the results of an analysis of microdata from the Scottish household survey. The survey provides a unique, large-scale, nationally representative data set that includes both a travel diary instrument and a pseudodiary of participation in online activity. Multivariate regression models were estimated to relate people's online-activity pro-files with their car driving mileage. The models included demographic and spatial characteristics to control for potential confounding effects. The analysis found that, net of other effects, compared with nonuse of the Internet, Internet usage was associated with a higher level of car use. The marginal effect of time spent online was, however, found to be negatively linked with car use. In other words, spending large amounts of time online is, all else equal, associated with less car driving mileage. The paper concludes with a discussion of further research needs to advance this line of inquiry.
Analysis of Imposed Bridge Load Stresses for Development of a European Bridge Formula
Authors: Moshiri Maryam , Montufar Jeannette
Published: July 2014

This paper evaluates the characteristics of international bridge formulas developed and implemented by different countries and analyzes the imposed bridge load effects resulting from trucks complying with international bridge formula–allowable loads and truck size and weight regulations in Europe. This evaluation was done to identify issues that may need to be considered in the development of a European bridge formula for the regulation of truck size and weight limits associated with international travel between European Union member states. Differences in national weight limits in European Union countries and the increasing demand for larger and heavier vehicles bring about the need to ensure the structural integrity and service life of bridges. Bridge formulas provide a method for regulating truck weights while ensuring the sustainability of infrastructure by allowing vehicle configurations that have an acceptable load effect on structures. This method allows for long-term truck size and weight evolutions for productivity gains while preserving the existing stock of bridges. The level of efficiency of a bridge formula varies depending on the design criteria used in the development of the formula, the compatibility of the jurisdiction's infrastructure and truck fleet characteristics, and the method of implementation as part of the regulation and by operators in the trucking industry. This research can help guide the development of a European bridge formula and contributes new knowledge for countries that currently apply a bridge formula to regulate truck weights.
Anchor Bolt Steel Strength in Annular Stand-Off Base Plate Connections
Authors: McBride Kenton E. , Cook Ronald A. , Prevatt David O. , Potter William
Published: July 2014

Anchor bolts in annular stand-off base plates connecting cantilever sign and signal structures to concrete foundations may experience high shear from base plate torsion and direct shear forces. A three-phase experimental study evaluated the steel shear strength of anchor bolts in grouted and ungrouted annular stand-off base plate connections to concrete. Phase 1 included flush-mounted and ungrouted stand-off base plates with ⅝- and 1-in.-diameter bolts loaded in direct shear. Phase 2 employed a novel torsion test approach on 10 circular groups of six ⅝-in.-diameter bolts installed in flush-mounted, ungrouted stand-off, and grouted stand-off base plates, along with three ungrouted groups of three 1-in.-diameter bolts. Phase 3 comprised one ungrouted and three grouted full-scale annular base plate tests of six 1.25-in.-diameter bolts under predominantly torsion loading. Results from this study suggest that AASHTO's provisions allowing bolt bending stresses to be ignored for anchor bolts with an exposed length of less than one bolt diameter overestimate ultimate strength. The beam model suggested by AASHTO accounting for anchor bolt bending fits experimental data well and is recommended for all ungrouted annular stand-off base plates. The American Concrete Institute's 0.8 reduction factor for steel shear strength of anchor bolts in grouted connections was found to be conservative and is also recommended.
Thermal Analysis of Highway Overhead Support Structures
Authors: Chang Byungik , Phares Brent M. , Zou Hao , Couch Todd
Published: July 2014

Dynamic message signs are increasingly used on freeways, expressways, and major arterials to manage traffic flow better by providing accurate and timely information to drivers. Overhead truss structures that allow for wide displays across multiple travel lanes are typically used to support those signs. Recently, cracks at welded toes in these structures have been identified in multiple states. The AASHTO standard specification defines the loads to be considered during design as wind load, dead load, live load, and ice load, and fatigue design for wind galloping, vortex shedding, natural wind gust, and truck-induced gust. Notably missing from this list is any consideration for thermal loads. Although the number of thermal cycles is relatively low, the temperature variations are relatively large. Should these large temperature ranges result in large stresses, the potential for fatigue failures to initiate, principally from thermal variations, exists. The objectives of this study were to investigate the influence of thermal- and wind-induced loads on bridge-type overhead truss support structures and to provide a resource aimed at improving current design specifications for thermal design. To provide a solid baseline for this work, field monitoring of several overhead trusses was conducted. The evaluation of the collected data was important for understanding the structural behavior and for the advancement of any future code provisions. In addition, finite element modeling was conducted to further study strain and stress magnitudes, which were compared with the field monitoring data. The fatigue life of the truss structures was also estimated on the basis of AASHTO specifications and the numerical modeling results.
Field Testing of Signal Head Vibration Absorber to Reduce Fatigue in Wind-Excited Traffic Signal Support Structures
Authors: Christenson Richard , Cashany Majid , Hua Jieying , Zuo Delong
Published: July 2014

The signal head vibration absorber (SHVA) is an effective vibration mitigation device proposed to reduce the in-plane wind-induced vibration and corresponding fatigue of traffic signal support structures. An SHVA was successfully tested in the Advanced Hazards Mitigation Laboratory at the University of Connecticut by being subjected to both free and force vibration testing with pluck tests and a linear shaker. A new SHVA design has been developed; it requires no modifications of standard signal heads or mounting hardware and is readily installable in the field for both retrofit and new applications. This paper provides research verification of the ability of an SHVA to reduce wind-induced vibration in traffic signal support structures. Successful field testing of a traffic signal support structure with a mast arm 60 ft (18.29 m) long was conducted at Texas Tech University's National Wind Institute Wind Engineering Research Field Laboratory. The field test results, consistent with prior laboratory testing, showed that the SHVA was able to reduce in-plane motion of the mast arm tip by 90%.
Concrete-Filled Steel Tubes for Accelerated Bridge Construction
Authors: Roeder Charles W. , Lehman Dawn E. , Stephens Max
Published: July 2014

Concrete-filled steel tubes (CFSTs), which are steel tubes with concrete infill, have increased strength, stiffness, and deformability relative to comparably sized reinforced concrete columns. The steel is at its optimal location and thus maximizes strength and stiffness while minimizing weight and material requirements and providing confinement to the concrete infill. In turn, the infill delays local and global buckling of the tube. In addition to their high resistance and stiffness properties, CFSTs are easily and rapidly constructed and eliminate the need for formwork and reinforcement. In bridge design, CFSTs may be used for bridge piers, shafts, caissons, and columns. However, the use of these tubes is limited in part because AASHTO design specifications for CFSTs are dated and in part because few validated, constructible connections exist. The American Institute of Steel Construction (AISC) includes more recent updates to CFST design provisions than does AASHTO. This paper compares current CFST design provisions with experimental results, noting limitations and deficiencies. Proposed provisions to improve the AISC provisions are introduced. These improved provisions are used as the basis of new AASHTO specifications for use of CFSTs in bridge design. Connections, which are a second limitation in CFST design, are also discussed. A foundation connection capable of developing the composite capacity of a CFST was evaluated experimentally and resulted in design expressions. A preliminary study of CFST column–to–cap beam connections using numerical simulation is introduced. This paper presents significant advancement and practical methods for the use of CFSTs in bridge design.
Model for Nominal Bond-Shear Capacity of Pretensioned Concrete Girders
Authors: Ross Brandon E. , Naji Behnam
Published: July 2014

The 2010 AASHTO LRFD Bridge Design Specifications includes requirements for proportioning flexural reinforcement at the end of pretensioned girders to carry longitudinal tie forces acting above the support. To prevent bond failure of the longitudinal tie, AASHTO requires that “any lack of full development [of the tie] shall be accounted for.” This paper proposes a model for calculating nominal bond-shear capacity, which is defined as the attendant shear force at bond capacity of the longitudinal tie. The model gives explicit consideration for tie development length. Variables in the model include bearing and girder geometry, longitudinal and transverse reinforcement details, and inclination angle of cracking. Derivation of the model is presented, and the model is compared with a database of experimental results compiled from the published literature. The proposed model can be used for designing girders that are resistant to bond-shear failure, particularly when partial strand debonding is employed. In some circumstances the model may justify exceedance of the AASHTO limits for partial strand debonding.
Testimonio and secrecy in a traumatic past
Authors: González Olga
Published: July 2014

This article discusses the fate of dangerous memories of war associated with the “internal armed conflict” in Peru. It focuses on the Andean community of Sarhua in Ayacucho and their experiences with political violence as depicted in a collection of paintings, Piraq Causa (Who Is Still to Blame?). A close examination of this visual testimonio reveals that some dangerous memories have been denied representation. I suggest that these become silences and absences that give expression to a “traumatic gap”, which includes memories of fratricidal violence and the community's initial endorsement of the Maoist Shining Path. I argue that Piraq Causa reflects the magnified secrecy around events that the community agreed to deliberately “remember to forget”. In so doing, I also propose that the perceived gaps in the pictorial narrative provoke the unmasking of what is “secretly familiar” in Sarhua. To that extent, Piraq Causa exposes as much as it affirms the secrecy around traumatic memories of war.
Single space transforaminal lumbar interbody fusion in spondylolisthesis: initial experience of 30 cases
Authors: Islam MA , Sakeb N , Sarker SK
Published: July 2014

Spondylolisthesis in adults is characterized by the loss of disc height across the affected segment with sagital translation. The goal of stabilizing the spine is accomplished by fusion. Transforaminal approach for lumbar interbody fusion is a very good approach and reduces the complications associated with traditional posterior approach. It has been reported to be safe and effective in the treatment of spondylolisthesis. It has done to assess the functional outcome of Transforaminal Lumbar Interbody Fusion (TLIF) in spondylolisthesis. This prospective interventional study was performed from July 2008 to June 2011 included 30 patients (male 07, female 23), within a age range of 30-59 years. Nineteen cases were lytic, 08 cases were degenerative, 02 were post-traumatic and 01 dysplastic variety of spondylolisthesis. Follow up ranged from 12 to 24 months and outcome assessed by VAS and ODI regarding pain and disability. Achievement of fusion and complications were documented accordingly. Statistical analysis was done by unpaired t-test and chi-squared test in appropriate instances. We included twenty 0ne (70.00%) patient had Grade-II Spondylolisthesis and L4 over L5 had been the commonest level (53.33%) involved. Pain and disability improved significantly and 22 (73.33%) patients returned to their previous level of activity. One (03.33%) patient developed superficial wound infection and 01 (03.33%) had persistent low back pain. All patients had neurological improvement. We concluded that Transforaminal Lumbar Interbody Fusion is an effective alternative surgical procedure for the treatment of spondylolisthesis. Overall outcome is satisfactory in 93.33% cases.DOI: http://dx.doi.org/10.3329/bmrcb.v39i2.19640 Bangladesh Med Res Counc Bull 2013; 39: 47-51
A comparative study of chemical and immunological method of fecal occult blood test in the diagnosis of occult lower gastrointestinal bleeding
Authors: Yeasmin F , Ali MA , Rahman MA , Sultana T , Rahman MQ , Ahmed ANN
Published: July 2014

Fecal occult blood test is the most widely used screening test for diagnosis of gastrointestinal bleeding disorders specially colorectal carcinoma. Among the various methods of fecal occult blood tests, chemical method is being used commonly, but the method has some drawbacks like low participation rate, high false positive rate, low sensitivity etc. To overcome these short comings, newer immunological method was introduced. This study evaluated the role of immunological method of fecal blood test in the diagnosis of occult lower GIT bleeding. Stool samples from two hundred patients were examined by both chemical and immunological method. The patients who were positive by any or both methods of occult blood test, were advised for colonoscopy. During colonoscopy tissues were taken for histopathology which was the gold standard of this study. Among 110 OBT positive patients pathological lesions were detected in 65 patients by colonoscopy and histopathology. The diseases detected by colonoscopy and histopathology 18 colorectal polyp, 8 colorectal cancer, 24 ulcerative lesions and 5 inflammatory bowel disease etc. Regarding comparative analysis of chemical and immunological method, the higher sensitivity (95.4% vs. 49.2%), specificity (44.4% vs. 37.8%), accuracy (74.5% vs. 44.5%), PPV (71.3% vs. 53.3%) and NPV (87% vs. 34%) of immunological method than chemical method was observed. Thus immunological method of fecal occult blood test was appeared to be a better alternative to conventional chemical method of fecal occult blood test in the diagnosis of occult lower GIT bleeding. DOI: http://dx.doi.org/10.3329/bmrcb.v39i2.19641 Bangladesh Med Res Counc Bull 2013; 39: 52-56
Disseminated intravascular coagulation in acute promyelocytic leukaemia and its impact on the induction failure: a single centre study
Authors: Rahman F , Kabir AL , Khan MR , Aziz A , Baqui MN , Dipta TF , Yunus ABM
Published: July 2014

Life-threatening coagulopathy associated with acute promyelocytic leukemia (APL) has been the defining clinical characteristic and is an important risk factor for fatal haemorrhage and early death. Pathogenesis of coagulopathy in APL is complex and mainly includes disseminated intravascular coagulation (DIC). The study was done to see the status of DIC and its impact on the outcome of APL in our setting. Among the total 60 patients, induction mortality rate was 30% and remission rate was 70%. The main cause of induction mortality was bleeding that accounts for 66.7% of mortality. DIC was present among 32 out of 60 patients (53.33%). Induction mortality has significant relationship to DIC as the induction mortality rate is 47% in patients with DIC and 11% in patient without DIC (P value 0.0009 ). Induction motality rate in low, intermediate and high risk group is 6.7%, 24% and 58% respectively (p value <0.0001). Finally, risk group subclassification revealed presence of DIC in high risk group has the highest early mortality rate DOI: http://dx.doi.org/10.3329/bmrcb.v39i2.19642 Bangladesh Med Res Counc Bull 2013; 39: 57-60