bluuebunny/crossref_metadata_2025 huggingface dataset:
Gestational Diabetes Mellitus in Relation to Maternal Dietary Heme Iron and Nonheme Iron Intake
Authors: Qiu Chunfang , Zhang Cuilin , Gelaye Bizu , Enquobahrie Daniel A. , Frederick Ihunnaya O. , Williams Michelle A.
Published: June 2011

OBJECTIVE

Higher heme iron intake is associated with increased type 2 diabetes risk. However, no previous study has evaluated gestational diabetes mellitus (GDM) risk in relation to heme iron intake during pregnancy. We investigated associations of maternal preconceptional and early pregnancy heme and nonheme iron intake with subsequent GDM risk.

RESEARCH DESIGN AND METHODS

We conducted a prospective cohort study of 3,158 pregnant women. A food frequency questionnaire was used to assess maternal diet. Multivariable generalized linear regression models were used to derive estimates of relative risks (RRs) and 95% CIs.

RESULTS

Approximately 5.0% of the cohort developed GDM (n = 158). Heme iron intake was positively and significantly associated with GDM risk (Ptrend = 0.04). After adjusting for confounders, women reporting the highest heme iron intake levels (≥1.52 vs. <0.48 mg per day) experienced a 3.31-fold–increased GDM risk (95% CI 1.02–10.72). In fully adjusted models, we noted that a 1-mg per day increase in heme iron was associated with a 51% increased GDM risk (RR 1.51 [95% CI 0.99–2.36]). Nonheme iron was inversely, though not statistically significantly, associated with GDM risk, and the corresponding RRs were 1.00, 0.83, 0.62, and 0.61 across quartiles of nonheme iron intake (Ptrend = 0.08).

CONCLUSIONS

High levels of dietary heme iron intake during the preconceptional and early pregnancy period may be associated with increased GDM risk. Associations of GDM risk with dietary nonheme iron intake are less clear. Confirmation of these findings by future studies is warranted.
Regeneration of Pinus wallichiana AB Jackson in a trans-Himalayan dry valley of north-central Nepal
Authors: Ghimire Balkrishna , Mainali Kumar P , Lekhak Hari Datta , Chaudhary Ram Prasad , Ghimeray Amal Kumar
Published: June 2011

We studied the elevational pattern of forest composition and regeneration of the subalpine conifer tree species Pinus wallichiana in Manang, a trans-Himalayan dry valley in north-central Nepal. Thirty-five quadrats (10 m × 10 m) were laid between 3300 and 4000 masl on both north- and south-facing slopes. We measured diameter at breast height (DBH) of each mature individual of all tree species (DBH ≥10 cm), and recorded the number of seedlings (DBH <10 cm, height <30 cm) and saplings (DBH <10 cm, height >30 cm). We also measured soil moisture and soil pH, estimated canopy cover, and recorded slope and altitude in each quadrat. For all species together and for several species individually, tree density, seedling density, sapling density and tree basal area were found to decrease with elevation on both north and south aspects. This trend is largely explained by the progressively harsher environment at higher elevations. The north-facing slopes in our study area have denser forests than the south-facing slopes, the density of all size classes (seedling, sapling and mature plants) and basal area being greater on the northern aspects. These aspect-wide differences are attributable to the stark difference in soil moisture between northern and southern aspects, which is in turn due to the difference in insolation. Irrespective of elevation and aspect, all the forests studied are regenerating, as indicated by inverse J-shaped density-diameter curves. The elevational pattern of seedling and sapling abundance is explained only by elevation. Whereas other variables (e.g., canopy) are considered to have an important influence on seed germination and seedling establishment, they turn out not to be significant predictors of density of seedlings and saplings. This failure to identify a relationship is probably due to our use of non-parametric test (tree regression analysis) that we used to establish the relationship between density and its potential explanatory variables or due to our selection of 1 standard error rule yielding sub-optimal models for regression trees. Key words: density-diameter curve; regeneration; seedling; sapling; altitude; canopy; Manang Valley DOI: http://dx.doi.org/10.3126/hjs.v6i8.1798 Himalayan Journal of Sciences Vol.6 Issue 8 2010 pp.19-26
Microbial biomass and activity in high elevation (>5100 meters) soils from the Annapurna and Sagarmatha regions of the Nepalese Himalayas
Authors: King Andrew J , Karki Debendra , Nagy Laszlo , Racoviteanu Adina , Schmidt Steve K
Published: June 2011

High elevation subnival-zone soils are increasing in spatial extent in the Himalayas due to glacial retreat and grazing pressures. These seemingly barren soils actually harbor significant microbial diversity but have remained mostly unstudied in all of the major mountain ranges of the Earth. Here we describe a preliminary survey of subnival-zone soils and one vegetated high-elevation soil in the Annapurna and Sagarmatha regions of the Nepalese Himalayas. We examined microbial biomass and activity as well as key microclimatic and edaphic variables that may control microbial activity in these soils. Microbial biomass carbon levels were the lowest ever reported for any soil to date, whereas microbial nitrogen and soil enzyme activities were similar to levels measured in previous studies of subnival-zone soils of Peru and Colorado. Our initial studies also indicate that soil water availability is the primary limiting factor for life in these high-elevation soils. Key words: Microbial; soil; biogeochemistry; subnival; extracellular enzymes; microbial biomass DOI: http://dx.doi.org/10.3126/hjs.v6i8.2303 Himalayan Journal of Sciences Vol.6 Issue 8 2010 pp.11-18
Optimization of RAPD-PCR conditions for the study of genetic diversity in Nepal’s Swertia chirayita (Roxb. Ex Fleming) H. Karst
Authors: Shrestha Sangita , Sijapati Jaishree , Rana Neesha , Malla Diwa , Regmi Prabha , Raskoti Bhakta
Published: June 2011

Of the 30 species (including five varieties) of the genus Swertia in Nepal, nine have been reported to possess medicinal properties. Among these, S. chirayita is the most valuable species, with high demand in domestic and international markets. Nepal’s S. chirayita and related species are being recklessly exploited for commercial purposes. Two problems that have emerged with this lucrative market are (a) adulteration and fraudulent labeling of S. chirayita, and (b) depletion of S. chirayita and allied species from their natural habitats. To address the problem of adulteration and conservation, we studied molecular genetic diversity in S. chirayita populations and developed a molecular diagnostic tool for the purposes of authentication. We studied intra-specific genetic diversity in S. chirayita using Polymerase Chain Reaction (PCR)-based Random Amplified Polymorphic DNA (RAPD) technique. As a preliminary step, we identified optimal RAPD-PCR reaction and cycling conditions by varying PCR reaction parameters such as concentration of template DNA, MgCl2, dNTPs, primer, Taq DNA polymerase and RAPD-PCR programs. The optimized PCR reaction and cycling conditions were then used in subsequent RAPD profiling experiments for the study of genetic diversity within S. chirayita populations from various geographical locations. Genetic diversity characterization of S. chirayita populations at the molecular level would furnish information with significant applications in the conservation and sustainable utilization of S. chirayita and its allied species in Nepal. Key words: Polymerase Chain Reaction, Random Amplified Polymorphic DNA, DNA fingerprinting, genetic diversity DOI: http://dx.doi.org/10.3126/hjs.v6i8.2699 Himalayan Journal of Sciences Vol.6 Issue 8 2010 pp.35-40
Climate change and disease risk in the Himalayas
Authors: Sarkar Sahotra
Published: June 2011

A new challenge is unfolding in the Himalayas: a significant increase in the burden of infectious disease, driven by climate change. Vectors are moving beyond their historic ranges to higher elevations; water quality is deteriorating, and the available supply is diminishing. Preventive and ameliorative measures to address these problems require robust quantitative estimates of the size and spatial distribution of disease risk. Once enough data are available, disease risk can be mapped with predictive models so that appropriate policies can be formulated and implemented. Unfortunately, there has been virtually no quantitative epidemiological attention to this region.DOI: http://dx.doi.org/10.3126/hjs.v6i8.4921 Himalayan Journal of Sciences Vol.6 Issue 8 2010 pp.7-8
The European Sovereign Debt Crisis: Is Germany to Blame?
Authors: Young Brigitte , Semmler Willi
Published: June 2011

Only a decade ago, slow growth and high unemployment plagued Germany, but the "sick man of Europe" has now moved to outperform the Eurozone average growth since the second quarter of 2010. This confirms Germany's recovery and its status as the growth engine of the continent. This surely is a success story. While Germany (also Austria and the Netherlands) is prospering, the peripheral countries in the Eurozone are confronted with a severe sovereign debt crisis. Starting in Greece, it soon spread to countries such as Ireland, Portugal, and Spain. In the course of the debate, Germany was blamed for the imbalances in Europe. In short, German export performance and the sustained pressure for moderate wage increases have provided German exporters with the competitive advantage to dominate trade and capital flows within the Eurozone. Thus, Germany is seen as the main beneficiary of the EURO. This argument, however, is vehemently disputed within Germany. Many economists and political leaders reject this argument and point to the flagrant lack of fiscal discipline in many of the peripheral countries. Some prominent economists, such as Hans-Werner Sinn, even disputes that Germany was the main beneficiary of the Eurozone. The paper analyzes the two sides of the controversy, and asks whether we are witnessing a more inwardlooking and Euroskeptic Germany. These issues will be analyzed by first focusing on the role of Germany in resolving the sovereign debt crisis in Greece, and the European Union negotiations for a permanent rescue mechanism. We conclude by discussing some possible explanations for Germany's more assertive and more Euroskeptic position during these negotiations.
The Relationship of Nitrogen and C/N Ratio with Secondary Metabolites Levels and Antioxidant Activities in Three Varieties of Malaysian Kacip Fatimah (Labisia pumila Blume)
Authors: Ibrahim Mohd Hafiz , Jaafar Hawa Z.E.
Published: June 2011

Kacip Fatimah (Labisia pumila Blume), one of the most famous and widely used herbs, especially in Southeast Asia, is found to have interesting bioactive compounds and displays health promoting properties. In this study, the antioxidant activities of the methanol extracts of leaves, stems and roots of three varieties of L. pumila (var. alata, pumila and lanceolata) were evaluated in an effort to compare and validate the medicinal potential of this indigenous Malaysian herb species. The antioxidant activity determined by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, as well as the total amount of phenolics and flavonoids were the highest in the leaves, followed by the stems and roots in all the varieties. A similar trend was displayed by the ferric reducing antioxidant potential (FRAP) activity, suggesting that the L. pumila varieties possess high foliar antioxidant properties. At low FRAP activity concentrations, the values of the leaves’ inhibition activity in the three varieties were significantly higher than those of the stems and roots, with var. alata exhibiting higher antioxidant activities and total contents of phenolics and flavonoids compared to the varieties pumila and lanceolata. The high production of secondary metabolites and antioxidant activities in var. alata were firmly related to low nitrogen content and high C/N ratio in plant parts. The study also demonstrated a positive correlation between secondary metabolite content and antioxidant activities, and revealed that the consumption of L. pumila could exert several beneficial effects by virtue of its antioxidant activity.
Glomerular Dysfunction and Associated Risk Factors over 4–5 Years following Antiretroviral Therapy Initiation in Africa
Authors:   the DART Trial Team, Stöhr Wolfgang , Reid Andrew , Walker A Sarah , Ssali Francis , Munderi Paula , Mambule Ivan , Kityo Cissy , Grosskurth Heiner , Gilks Charles F , Gibb Diana M , Hakim James
Published: June 2011

Background

The aim of this study was to investigate long-term renal function in HIV-infected adults initiating antiretroviral therapy (ART) with a CD4+ T-cell count <200 cells/mm3 in Africa.

Methods

This was an observational analysis within the DART trial randomizing 3,316 adults to routine laboratory and clinical monitoring (LCM) or clinically driven monitoring (CDM). Serum creatinine was measured pre-ART (all ≤360 μmol/l), at weeks 4 and 12, then every 12 weeks for 4-5 years; estimated glomerular filtration rate (eGFR) was determined using the Cockcroft-Gault formula. We analysed eGFR changes, and cumulative incidences of eGFR<30 ml/min/1.73 m2 and chronic kidney disease (CKD; <60 ml/min/1.73 m2 or 25% decrease if <60 ml/min/1.73 m2 pre-ART; confirmed >3 months).

Results

At ART initiation, median CD4+ T-cell count was 86 cells/mm3; 1,492 (45%) participants had mild (60–<90 ml/min/1.73 m2), 237 (7%) moderate (30–<60 ml/min/1.73 m2) and 7 (0.2%) severe (15–<30 ml/min/1.73 m2) decreases in eGFR. First-line ART was zidovudine/lamivudine plus tenofovir (74%), abacavir (9%) or nevirapine (17%). By 4 years, cumulative incidence of eGFR<30 ml/min/1.73 m2 was 2.8% ( n=90) and CKD was 5.0% ( n=162). Adjusted eGFR increases to 4 years were 1, 9 and 6 ml/min/1.73 m2 with tenofovir, abacavir and nevirapine, respectively ( P<0.001), and 4 and 2 ml/min/1.73 m2 for LCM and CDM, respectively ( P=0.005; 2 and 3 ml/min/1.73 m2 to 5 years; P=0.81).

Conclusions

On all regimens and monitoring strategies, severe eGFR impairment was infrequent; differences in eGFR changes were small, suggesting that first-line ART, including tenofovir, can be given safely without routine renal function monitoring.
La pulsion esthétique
Authors: Chouvel Jean-Marc
Published: June 2011

Résumé La notion de pulsion élaborée par la psychanalyse ne donne guère de place à la jouissance esthétique, sauf à en faire un substitut ou une « sublimation » de la pulsion sexuelle. Cette manière de concevoir la réalité du phénomène artistique fait trop peu de cas d’une motivation essentielle du vivant, qui tourne autour de la notion de beauté. La musique est plus particulièrement cet art qui nous parle sans que nous en connaissions la langue. Il s’agira de sonder, à travers l’histoire de la pensée – et à travers le miroir du temps – ce qui fait de l’esthétique le moment le plus intense de la manifestation d’un inconscient qui est autant dans notre corps et dans nos sens que dans notre tête, et qui est autant dans le monde qu’en nous-même.
Temps, interprétation et urgence subjective
Authors: Lucchelli Juan Pablo
Published: June 2011

Résumé Nul n’ignore que la psychanalyse, ainsi que la psychothérapie analytique, procèdent dans les cures par l’interprétation. Ce procédé adopte différents visages selon les cas et selon les types de traitement. Même dans les suivis brefs, l’interprétation opère, bien avant parfois qu’un transfert s’établisse. Nous développons ce sujet et présentons un exemple clinique de « trouble anxieux » traité dans un moment d’urgence subjective. Nous voulons démontrer le rapport étroit existant entre interprétation, temps et apaisement symptomatique.
Pour une approche renouvelée de l'opposition politique
Authors: Brack Nathalie , Weinblum Sharon
Published: June 2011

Résumé En dépit du caractère central de l’opposition en démocratie, peu de recherches théoriques ont été menées sur cette question depuis les années 1970, alors même que le contexte dans lequel l’opposition a été conceptualisée à l’époque a changé de manière fondamentale. Pour cette raison, l’article vise à offrir une nouvelle perspective de l’opposition politique dans les démocraties contemporaines. Après une revue critique de la littérature classique et contemporaine sur le sujet, l’article propose une définition renouvelée de l’opposition qui permettrait de mieux saisir la complexité des dimensions de l’opposition politique. L’article propose également un nouvel agenda de recherche potentiel pour de futures recherches.
Les partis dans l'opposition en Europe centrale et orientale : un déclin inévitable ?
Authors: Cholova Blagovesta
Published: June 2011

Résumé Comment peut-on expliquer le déclin des partis en opposition en Europe centrale ? Afin de répondre à cette question, l’article tente d’abord de déterminer si ce constat est valable pour tous les partis restant en opposition pendant plus d’une législature dans cette région. Après avoir vérifié ce constat, il examine les facteurs qui peuvent expliquer ce phénomène. Il se concentre sur deux dimensions : externe (le facteur contextuel) et interne (le facteur organisationnel) en prenant en compte le développement des systèmes partisans dans cette région et les scissions au sein des partis pendant qu’ils restent en opposition.
S'opposer au sein du Parlement européen : le cas des eurosceptiques
Authors: Brack Nathalie
Published: June 2011

Résumé Cet article étudie les conceptions et pratiques du mandat représentatif des eurosceptiques au Parlement européen en tant qu’opposants anti-système. Il s’agit d’une part de déterminer dans quelle mesure les eurosceptiques durs ( hard ) ont une vision unifiée de leur mandat et des caractéristiques comportementales similaires ou s’il existe une certaine diversité en leur sein. Nous montrerons que ces élus endossent 3 types de rôle : le tribunitien, l’absent et le pragmatique. D’autre part, nous montrerons que la combinaison originale de facteurs institutionnels et individuels permet d’expliquer le choix d’un rôle par ces élus.
Occupational Performance Problems in 85-Year-Old Women and Men in Sweden
Authors: Källdalen Anette , Marcusson Jan , Nägga Katarina , Wressle Ewa
Published: June 2011

An area of concern for occupational therapy is to increase preventive interventions among relatively healthy elderly individuals. The purpose of this study was to explore occupational performance problems among 85-year-old women and men in relation to demographic data, mental health, and health-related quality of life. Participants completed a postal questionnaire including the EuroQoL health-related quality of life measurement. Instruments used during a home visit were the Canadian Occupational Performance Measure, the Mini-Mental State Examination, and the Geriatric Depression scale. The sample comprised 380 individuals. Women experienced poorer health and more occupational performance problems in community management, household management, and quiet leisure than men. Impaired cognitive function, lower self-rated health, and higher risk of depression correlated with a larger number of occupational performance problems. Intervention planning should be based on individual perceptions of meaningful occupations and environmental considerations.
Reliability and Validity of the Valued Activity Inventory for Adults with Cancer
Authors: Lyons Kathleen Doyle , Hegel Mark T. , Hull Jay G. , Li Zhongze , Balan Stefan , Bartels Stephen
Published: June 2011

The authors assessed the psychometric properties of the Valued Activity Inventory for Adults With Cancer (VAI-AC), a self-report instrument that measures activity limitations. Participants included 50 older adults undergoing chemotherapy who completed the VAI-AC and measures of physical and mental function, symptom intensity, and mood 3 days before and the day of chemotherapy. Test—retest reliability was assessed by determining the average number of items for which the importance of an activity was rated consistently and by calculating the intraclass correlation coefficient (ICC) for the first and second VAI-AC scores. Convergent validity was assessed by correlating the VAI-AC scores with the other measures. Participants consistently rated the importance of 90% of the items. The 72-hour test—retest reliability ICC was 0.67. Participants with fewer activity limitations indicated better physical function ( r = 0.58, p < .001), better mental function ( r = 0.55, p < .001), lower symptom intensity ( r = −0.57, p < .001), and fewer depressive symptoms ( r = −0.68, p < .001). The VAI-AC demonstrated evidence of test—retest reliability and convergent validity in this convenience sample of older adults undergoing chemotherapy for cancer.
TNF Receptor 1 Mediates Dendritic Cell Maturation and CD8 T Cell Response through Two Distinct Mechanisms
Authors: Ding Xilai , Yang Wei , Shi Xiaodong , Du Peishuang , Su Lishan , Qin Zhihai , Chen Jianzhu , Deng Hongyu
Published: June 2011

TNF-α and its two receptors (TNFR1 and 2) are known to stimulate dendritic cell (DC) maturation and T cell response. However, the specific receptor and mechanisms involved in vivo are still controversial. In this study, we show that in response to an attenuated mouse hepatitis virus infection, DCs fail to mobilize and up-regulate CD40, CD80, CD86, and MHC class I in TNFR1−/− mice as compared with the wild-type and TNFR2−/− mice. Correspondingly, virus-specific CD8 T cell response was dramatically diminished in TNFR1−/− mice. Adoptive transfer of TNFR1-expressing DCs into TNFR1−/− mice rescues CD8 T cell response. Interestingly, adoptive transfer of TNFR1-expressing naive T cells also restores DC mobilization and maturation and endogenous CD8 T cell response. These results show that TNFR1, not TNFR2, mediates TNF-α stimulation of DC maturation and T cell response to mouse hepatitis virus in vivo. They also suggest two mechanisms by which TNFR1 mediates TNF-α–driven DC maturation, as follows: a direct effect through TNFR1 expressed on immature DCs and an indirect effect through TNFR1 expressed on naive T cells.
Hepatitis C and Kidney Transplantation
Authors: Carbone Marco , Cockwell Paul , Neuberger James
Published: June 2011

Hepatitis C virus (HCV) infection is relatively common among patients with end-stage kidney disease (ESKD) on dialysis and kidney transplant recipients. HCV infection in hemodialysis patients is associated with an increased mortality due to liver cirrhosis and hepatocellular carcinoma. The severity of hepatitis C-related liver disease in kidney transplant candidates may predict patient and graft survival after transplant. Liver biopsy remains the gold standard in the assessment of liver fibrosis in this setting. Kidney transplantation, not haemodialysis, seems to be the best treatment for HCV+ve patients with ESKD. Transplantation of kidneys from HCV+ve donors restricted to HCV+ve recipients is safe and associated with a reduction in the waiting time. Simultaneous kidney/liver transplantation (SKL) should be considered for kidney transplant candidates with HCV-related decompensated cirrhosis. Treatment of HCV is more complex in hemodialysis patients, whereas treatment of HCV recurrence in SLK recipients appears effective and safe.
Fatal Hemothorax Caused by Pseudomesotheliomatous Carcinoma of the Lung
Authors: Snaebjornsson Petur , Vos Cornelis G. , Hartemink Koen J. , Lely Rutger J. , Samii Setareh M. , Grünberg Katrien , Paul Marinus A.
Published: June 2011

We present a case of a poorly differentiated pseudomesotheliomatous carcinoma originating in the lung, which was manifested with the distinctly rare complication of massive true hemothorax and persistent blood loss that proved rapidly fatal in spite of surgery. Pseudomesotheliomatous carcinoma of the lung and neoplasia-associated hemothorax are reviewed and discussed.
Advances in Fine Needle Aspiration Cytology for the Diagnosis of Pulmonary Carcinoma
Authors: Hasanovic Adnan , Rekhtman Natasha , Sigel Carlie S. , Moreira Andre L.
Published: June 2011

New developments in the field of thoracic oncology have challenged the way pathologists approach the diagnosis of pulmonary carcinoma. Nonsmall cell carcinoma is no longer an adequate diagnostic category. Pathologists are required to further classify tumors into adenocarcinoma and squamous cell carcinoma since specific therapies are now recommended depending on the histological tumor type. This change occurred following the discovery of specific molecular alterations that predict response to certain drugs and now molecular testing of tumor cells is often requested to direct therapy. The vast majority of lung cancer is diagnosed in advanced clinical stages, where cytologic or small biopsy material is the only form of tissue diagnosis, thus placing cytology, especially fine needle aspiration biopsy in the front line for management of patients with lung cancer. In this paper we will review the current concepts in the suitability and accuracy of fine needle aspiration biopsy, including diagnosis, classification, prognostic markers, and use of ancillary techniques.
Microseparation and Stripe Wear in Alumina-On-Alumina Hip Implants
Authors: Affatato Saverio , Traina Francesco , Toni Aldo
Published: June 2011

The combination of materials that still has highest wear resistance for total hip replacement is ceramic-on-ceramic. However, brittleness is a major concern for ceramics: in vivo and in vitro studies on ceramic hip prostheses correlate microseparation with hip noise, ceramic wear, or ceramic liner damage. Ceramic microseparation can lead to edge load, ceramic head wear, and squeaking.

The aim of this in vitro study was to investigate whether different angles of inclination influence the wear pattern of alumina-on-alumina hip joints with micro-separation during the swing phase. We also evaluated the wear rate obtained from this in vitro investigation with retrieval specimens obtained at 13 years' mean follow-up.

The study was performed using a 12-station hip joint wear simulator (Shore Western, Monrovia, CA, USA) under bovine calf serum used as lubricant. Wear was evaluated by the gravimetric method and the test length was set at two million cycles.

After two million cycles, a volumetric loss of 0.11 ±0.03 mm3 and 0.12 ±0.06 mm3 was observed, respectively, for 23° and 63° angles of inclination. In particular, the results obtained in this work revealed an increase of about 12-fold compared to previous results without microseparation conditions. No significant differences were observed between the two different inclinations on the wear patterns of the acetabular cups with a level of significance of α = 0.5. The location and general shape of the stripes wear were similar for the retrieved and simulator balls.
Port City Factors and Port Production: Analysis of Chinese Ports
Authors: Cheung Shuk Man Sherman , Yip Tsz Leung
Published: June 2011

The objective of this article is to analyze port production activities and city factors in port cities. Port activities take place in port cities and the analysis provides a good opportunity to integrate the study of ports and cities. The study uses the economic production equation to analyze the production of China's ports over the time period 1995–2007. Numerous studies have examined general port growth and development on the basis of conceptual discussion. It is generally accepted that the Anyport Model and the Port Generation Model are valuable models for analysis of a port developing into a port city. However, empirical studies on port growth and factors that influence the growth rate are rather few. This study seeks to identify the city factors that are critical in determining port growth and attempts to develop an empirical model in the macroeconomic perspective. Seven major China port cities and their interfaces with their associated ports are studied here. This article attempts to analyze the port activities as economic production outputs and the city factors as inputs. The article provides an empirical analysis of port growth and policy insights on the interdependence between ports and port cities.
Air Travel in Small Communities: An Econometric Framework and Results
Authors: Bhadra Dipasis
Published: June 2011

In this paper, we examine the relationship between origin and destination (O&D) travel and local area characteristics for small communities. By combining data from Bureau of Transportation Statistics/United States Department of Transportation (BTS/DOT) on O&D travel with that of local area economic and demographic activities supplied by the United States Bureau of Economic Analyses (BEA), Department of Commerce, we specify a semi-log linear demand relationship for O&D travel in small communities. The resultant dataset covering the period 1999-2000 has more than 4,700 observations; 2,686 for communities without any small hubs, and 2,087 for communities with small hubs. Using a weighted least squares method, we estimate demand for air travel, defined by O&D pairs, for smaller communities. Our results indicate that average fare affects passenger demand negatively for both types of communities. Our results also confirm that local area income affects travel positively in both cases. However, the levels of travel tend to be affected by population differently; origin population affecting traffic negatively for smaller communities without any hub and positively for communities with small hubs. Presence of smaller hubs affects air travel positively; and market concentration of airlines affects O&D travel negatively. We demonstrate in this paper that factors affecting the economic framework are the ultimate factors driving the demand for air travel in the small communities in the long run. We also discuss approaches using our methodology for deriving bottom-up projections. These projections have distinct characteristics that may make them more useful for analyzing flow features, such as passenger and aircraft flows by local areas, determining and prioritizing infrastructure investment requirements by local areas, and determining revenue potential from these travels.
Probabilistic Linkage Approach to Commercial Motor Vehicle and Carrier Datasets
Authors: Lee Jung-Taek , Thakuriah (Vonu) Piyushimita
Published: June 2011

In this paper, a probabilistic linkage method is explored in the context of linking databases in the Commercial Motor Vehicle and Carrier (CMVC) sector as a potential solution to overcome data quality problems. An application of this method is demonstrated by linking commercial motor vehicle inspection files kept by the Illinois State Police (ISP) and the inspection files available from the Illinois portion of the Motor Carrier Management Information System (MCMIS). Since one of the files to be matched is a subset of the other, the application allows us to validate the methodology. The results show 6,228 correct identifications of true matched record pairs out of 6,335 actual true matches (more than 99%) between the two files. The number of erroneously identified record pairs is 690 (about 11% of the actual true matched pairs.) Sensitivity analysis is conducted of error rates with respect to variations in the optimal thresholds for merging the databases. A simple analysis also shows how much of a clerical examination for unclear record pairs would have to be tolerated for a reduction in dollar expenditure.
Trends in the Use of Large Trucks by Truckload and Less-Than-Truckload Motor Carriers in the 1990s
Authors: Burks Stephen V. , Monaco Kristen , Myers-Kuykindall Josephine
Published: June 2011

Using information from the Economic Census, Motor Carrier Financial and Operating Statistics, and the Vehicle Inventory and Use Survey, trends are examined in specialization and in vehicle use in the truckload (TL) and less-than-truckload (LTL) segments of the for-hire trucking industry. The VIUS data show that capacity, output, and intensity of use vary significantly by segment. TL firms have almost three times as many large trucks as LTL firms and operate more than three times the annual total miles, a consequence of the fact that TL firms use their vehicles more intensely (mean annual miles) than LTL firms. This gap, however, closed slightly during the 1990s. Both types of operations shifted vehicles away from local toward long-haul service in the 1990s, but LTL, which is less specialized in this regard, shifted more sharply.
The Relative Efficiency in the Blending of Strategic Dimensions Utilized in the Generation of Customer Satisfaction in the LTL Motor Carrier Industry
Authors: Scheraga Carl A.
Published: June 2011

This preliminary study utilizes a data envelopment methodology to assess the strategic orientations of LTL motor carriers and their impact on customer satisfaction and firm profitability. Strategic orientations are described in terms of seven dimensions previously identified in the motor carrier literature. The study demonstrates that there are "best practice" configurations of the intensities of these strategic dimensions that most efficiently generate the maximum levels of customer satisfaction and perceived levels of service quality. It is shown how the data envelopment methodology provides motor carriers with a means of benchmarking their strategic orientations as well as identifying the competitors against whom such benchmarking should occur.
Understanding the Shared Operation of Commuter Rail Transit and Freight Railroads
Authors: Liu Rongfang (Rachel) , Yang Fei , Chen Mei
Published: June 2011

Seeking a thorough understanding of shared operation between commuter rail transit and freight railroads, a nationwide survey was conducted of transit and rail freight interaction. This survey contacted and received responses from all 21 commuter rail services in North America. In addition to a general understanding of the shared-use practices, this paper presents the key factors that contribute or impede successful shared-use operations between commuter rail and freight railroads by examining detailed operation arrangements, shared asset management, dispatching priorities, accident histories, and insurance and liability issues. A few critical issues directly related to the success of future shared operations are highlighted for the reference of new-start systems and those who are seeking knowledge in the arena of shared-use operations.
Quantification of the Accuracy of Low Priced GPS Receivers for Crash Location
Authors: Sando Thobias , Mussa Renatus , Sobanjo John , Spainhour Lisa
Published: June 2011

Global positioning system (GPS) has been identified as a potential tool for capturing crash location data. This study quantifies factors that could affect the accuracy of GPS receivers. The results showed that GPS receiver orientation, site obstructions, and weather have significant effects on the accuracy of GPS receivers. Time of day and number of satellites were not found to significantly affect the accuracy of GPS receivers. HDOP values of 1.2 or less were found to be adequate for crash location purposes. An accuracy improvement of 20.7% was realized by filtering GPS data based on HDOP values.
The Impact of Transportation Costs on Spatial Competition of Grain Buyers: An Iowa Case Study
Authors: Carriquiry Miguel A. , Babcock Bruce A.
Published: June 2011

Hotelling's classic model of spatial competition is adapted to estimate the impacts on grain price of the closure of one of three grain buyers on the Mississippi River in the vicinity of Scott County, Iowa. The customers of the buyer who is closing (River Gulf Grain Company) in Davenport, Iowa, are assumed to deliver their grain to a buyer in either Buffalo, Iowa, to the south or to a buyer in Clinton, Iowa, to the north. Calibration of Hotelling's framework to this situation leads to an estimated decline in grain bids of 1.5¢ per bushel for the buyer located in Clinton and by 2.5¢ per bushel for the buyer located in Buffalo. These estimates are based on an incremental transportation cost of 0.15¢ per mile between the seller's farm and the buyer. This price decline would reduce gross receipts of the farmers who currently deliver to Davenport by approximately $264,000 per year. The effect of lower price bids on gross receipts of all area farmers would be approximately $750,000 per year. Transportation costs would increase by an estimated $75,000 for those farmers who would have to haul their grain farther because of the closure.
Oil Pipeline Markets and Operations
Authors: Hull Bradley
Published: June 2011

Despite considerable literature regarding other modes of transportation, little is written about oil pipelines. This is remarkable given that oil pipelines move 17% of all intercity ton miles, but also understandable because they have a low public profile and, with near total automation, have few employees. This article attempts to bridge the gap by comparing pipeline operations and those of the other modes, showing striking similarities along with a few significant differences. It also portrays pipeline markets and their changing trends. In recent years, oil pipelines have served an industry that is experiencing rapidly shifting geographical markets, proliferation of new products, and outsourcing of transportation by shippers. The pipeline industry has responded to these challenges with increased competitive entry, numerous capital construction projects, and a high reliance on technology. These issues, along with the regulatory constraints and responses are portrayed.
Transportation Economics: Some Developments Over the Past 30 Years
Authors: Button Kenneth
Published: June 2011

This paper looks at the changes that have occurred since the 1970s in the types of economic tools used, the ways they have been used, and the impacts they have had in shaping the way we now understand transportation. Over the past 30 years, society's views on transport have changed and, with this, the issues to which we attach priority have altered. Additionally, there have been important changes in our more generic understanding of economics and this has added to the toolkit of concepts that can be applied to transport matters. The tradition of transportation economics up until the late 1960s was largely one of defining 'optimal' pricing principles in regulated markets, in understanding market domination for mergers and similar policies, and in providing advice to engineers dealing with investment decisions. There is now, however, an appreciation that providing transport services is more complex than was once thought and, therefore, it is better to leave as much as possible to market forces; but this has also happened at a time when our understanding of markets has changed. There has additionally been the emergence of novel political and governance structures, such as the Single European Market, that have resurrected older interests in such things as links between economic development and transport quality. Despite this shift to the market as a primary means of resource allocation, parallel moves have taken place to embrace more fully the external costs of environmental damage. The advent of computers, more sophisticated econometric and programming techniques, and the availability of new data sources, such as GIS, have facilitated more efficient estimation of parameters and added to the quantitative contribution of economics.
Intercept Surveys: Productivity in Collecting Truck Trip Data, A Case Study of Portland, Oregon
Authors: Jessup Eric , Casavant Ken , Lawson Catherine , Kirk Alan
Published: June 2011

This study examines and contrasts the use of intercept surveys at different locations (a highway roadside, a port and a warehouse) to generate details useful to states’ modeling and freight planning needs for truck movements, particularly at the sub-county level. Data collected at roadside locations provides complete trip detail for all inter-regional movements (highway locations) and also trip detail for almost all intra-regional freight movements (warehouse/distribution center locations). Interviews at the warehouse/distribution center and interstate highway weigh station provide the highest commodity type response rates, while the preponderance of container traffic at the port facility yields limited responses on payload information. Different locations yielded differing question response rates.
Optimal Winter Speed Limit
Authors: Thaneseun Suthipun , Kagaya Seiichi , Uchida Ken-etsu , Hagiwara Toru
Published: June 2011

This study aims to determine the optimal winter speed limit through the application of a cost analysis and by analysis of effects of road and traffic conditions. Initially, a cost analysis of travel time costs, vehicle operating costs, pollution costs, and accident cost was applied to determine optimal average speed on the basis of the minimum total cost. Then, the effects of road and traffic conditions were calculated by regression analysis. Finally, the optimal winter speed limits were achieved. In conclusion, we found that our model was reliable and the results were appropriate and sustainable for the long term.
A Model of Corn and Soybean Shipments on the Ohio River
Authors: Babcock Michael W. , Fuller Stehen
Published: June 2011

This paper estimates the demand for corn and soybean shipments on the Ohio River during the 1992-2004 period. Using monthly data, OLS (with Newewy-West standard errors) parameters estimates were obtained for the explanatory variables. Results indicate that Ohio River corn and soybean shipments are significantly and positively affected by one month lagged shipments, corn and soybean stocks in the Ohio River production region, and corn and soybean exports from lower Mississippi River Gulf ports. Some empirical support was found for a significant negative relationship between Ohio River corn and soybean shipments and ocean shipping freight rates from lower Mississippi River Gulf ports to Japan. Indiana corn prices did not significantly affect Ohio River corn and soybean shipments.
International Airports: Economies of Scale and Marginal Costs
Authors: Martin Juan Carlos , Voltes-Dorta Augusto
Published: June 2011

Regarding some regulation fields, such as optimal investments and pricing policies, marginal cost estimations for infrastructure-intensive transport services is always a challenging task. The lack of comparable data among airports is one of the causes which could explain the relative scarcity of this literature in the past. In this paper, the returns to scale and marginal costs are estimated using single-and multi-product translog specifications of a long-run cost function. A pooled database of financial data on 41 airports across Europe, North America, Asia, and Australia for the period 1991-2005 was used. Significant economies of scale and little degree of technological progress are found using Work Load Units (WLU) and Air Traffic Movements (ATM) as output measures. Additionally, individual long-run marginal cost estimates are provided for each output measure, and for every airport under study.
Analysis of Productivity Trends on Indian Railways
Authors: Alivelu G.
Published: June 2011

A large number of technological advancements have taken place on Indian Railways in recent times. Technological changes resulting in fuel and labor efficiency increase productivity and thereby reduce the cost of production on Indian Railways.

To assess the productivity performance on Indian Railways, two outputs and three inputs are considered for the period from 1981-82 to 2002-03. During this period, there was large structural change in capital stocks, especially with respect to rolling stock and equipment. Embodied new technology in terms of diesel and electric engines was added. The study clearly shows that technological progress must have been a very important factor leading to higher productivity.
A Simulation-Based Approximation Algorithm for Dynamic Marginal Cost Pricing
Authors: Karoonsoontawong Ampol , Ukkusuri Satish , Waller S. Travis , Kockelman Kara M.
Published: June 2011

This work offers a simulation-based approximation algorithm for dynamic marginal cost pricing (MCP) congestion pricing that is a direct extension of its static counterpart. The algorithm approximates the time-dependent marginal costs, and is incorporated into the inner approximation dynamic user equilibrium algorithm to evaluate the results of dynamic MCP, which are then compared to static assignment results with MCP from previous study. The status quo and dynamic MCP-on-freeways scenarios are simulated (and then compared) on the Dallas-Fort Worth 35,732-link network. Due to computational requirements for such a large-scale dynamic traffic assignment application, the dynamic MCP scenario is simulated without feedback, and only route choices are permitted to vary. When prices are imposed on freeway users, some minor system benefits are observed, including a delay in the onset of congestion. Dynamic prices vary substantially over the three-hour period of analysis, reflecting changes in freeway congestion. Reasons for any inconsistencies between dynamic and static results are discussed, along with important enhancements to future implementation.
Family conflicts and conflict resolution regarding food choices
Authors: Nørgaard Maria Kümpel , Brunsø Karen
Published: June 2011

Previous studies on family decision‐making show that not only parents but also children participate actively in and achieve influence on the decision process, for instance during food buying. When decision‐making includes several active participants, conflicts may occur, but not much research deals with food‐related conflicts, conflict resolutions or specific influence techniques with a focus on parents and tweens in family decision‐making. This article focuses on parents and tweens' joint decision processes in evaluation and choice of food, specifically conflicts and conflict resolution. Assumptions are explored in an empirical study of Danish families with children. The main results show that during food buying family communication is open for opinion statements and discussions between parents and their tweens. However, not everything is that overt in family communication. One of the most interesting findings and a new insight is tweens' use of the help technique with the aim of easing family life. It is unclear whether parents are aware of this ‘under cover’ influence and just accept tacitly or whether this method of influence is unrealised.

Copyright © 2011 John Wiley & Sons, Ltd.
Encouraging children to eat more healthily: The influence of packaging
Authors: Pires Carla , Agante Luísa
Published: June 2011

The objective of this study was to understand how food packaging can influence children's attitudes and purchase decisions toward healthier choices. The appealing components of junk food packaging were transferred onto healthy food in order to test its effect on children's package evaluation, attention to packaging attitude toward the product, perceived healthiness and purchase intention. A structured questionnaire was completed by a sample of 408 Portuguese children aged between 10 and 14 years. Findings suggest that food packaging can influence children's attitudes and purchase intentions. These results should be considered by food companies that target children and aim at improving their dietary habits. Copyright © 2011 John Wiley & Sons, Ltd.