bluuebunny/crossref_metadata_2025 huggingface dataset:
Genetic Algorithm–Based Column Generation Approach to Passenger Rail Crew Scheduling
Authors: Liu Mindy , Haghani Ali , Toobaie Shahabeddin
Published: September 2010

The goal of the present study was to develop and apply a genetic algorithm–based column generation heuristic to solve a passenger rail crew scheduling problem in North America. The crew scheduling problem minimized the total cost of payment to crew members on the basis of the number of hours on board, the number of hours held away from a crew base, the number of nights of lodging, and the number of onboard and away meals. Payment regulations also dictated an overtime payment and a guaranteed salary per week. Additional problem constraints included restrictions on the maximum number of continuous working hours, the maximum number of days worked per week, and the minimum number of hours of rest. The proposed heuristic produced solutions with improvements of total cost ranging from 3.0% to 27.9%.
Deploying Business Logic for Railway Infrastructure Charging
Authors: Macário Rosário , Teixeira Paulo , Rothengatter Werner
Published: September 2010

The policy of the European Commission indicates that charges for rail infrastructure should be related to the costs actually incurred, define incentives for more efficient use of the infrastructure, avoid discriminating against users, and allow public authorities to verify compliance with these objectives. European Commission Directives 2001/12/EC and 2001/14/EC define a general framework for the establishment of charges for the rail infrastructure; however, enormous difficulties have arisen in calculating marginal costs and allocating the full costs of the infrastructure to cost drivers. Over the years and as the need for infrastructure managers (IMs) to adopt a more commercially oriented attitude developed, it became vitally important for every IM to understand the link between accounting and charging, requiring the adoption of a business logic that ensures that the cost drivers are well identified and controllable and that investments are made by taking into account future needs. In fact, to face future needs, the cost accounting framework for railway infrastructure should deliver important background information for establishing charges. The framework should also allow comparison of the costs and revenues for each market segment in determining the services on which business activities should be focused and the levels of public funding required to fulfill public service obligation agreements as part of multiyear contracts with predefined levels of service. Finally, cost accounting frameworks for the railway infrastructure should also deliver accurate information for the regulator to ensure equity and fairness in railway market access. The main task for the regulator will be to check that the resulting differentiation of track prices is free of discrimination.
New Approach to Appraisal of Rail Freight Projects in South Korea
Authors: Kang Kyungwoo , Strauss-Wieder Anne , Eom Jin Ki
Published: September 2010

This paper contributes to the estimation of the value of rail freight transit time savings, reliability, and service frequency for producers and transport operators by using stated preference data for short-haul rail freight shipments in South Korea. To appraise investments in freight projects in South Korea, the mixed logit model was used to determine the value of rail freight transit time savings, resulting in an estimated savings of about $2.31/h per shipment. The value of rail freight reliability (the percentage of on-time arrivals and departures) is $2.78/h of delay and $0.54/day for scheduled freight service delay. The results for freight time value for different economic agents are surprising: shippers perceived the value of transit time, transit time reliability, and service frequency to be far higher than producers did. Shippers valued rail freight transit time savings at about $2.35/metric ton h, whereas this same value for producers was $1.21/metric ton h. When the time benefit based on these values was added to the preliminary feasibility evaluation for 20 freight railroad infrastructure projects in South Korea, the number of projects for which benefits outweighed costs increased from four to 11.
Effects of Communications-Based Train Control and Electronically Controlled Pneumatic Brakes on Railroad Capacity
Authors: Dingler Mark H. , Lai Yung-Cheng (Rex) , Barkan Christopher P. L.
Published: September 2010

Railroads are increasingly using new technologies to improve capacity and operating efficiency. To plan their investments and prepare for the implementation of these technologies, railroads must understand their net effect on operations. This requires understanding both the particular aspects of these technologies that affect capacity and the characteristics of the systems into which they are being introduced. Two important technologies in this regard are communications-based train control (CBTC) and electronically controlled pneumatic (ECP) brakes. Each element of CBTC and ECP brakes with the potential to affect capacity was identified, and its effect under various implementation scenarios was evaluated. The potential impact of each element was assessed and compared with the various baseline conditions and conventional technologies to understand the incremental effect. An extensive review of the literature on the subject was conducted in support of these evaluations. CBTC implementation with enforcement braking will generally result in a loss of capacity, but as these systems become more fully integrated, the potential for capacity enhancement improves. ECP brakes will provide benefits under most operational scenarios because of the shorter braking distances and thus the potential for the closer spacing of trains. The two technologies have a potential interactive effect: CBTC may make it possible to more effectively take advantage of one of the principal benefits of ECP brakes: shorter stopping distances. The results for either technology will be route and network specific, so individual railroads will need to conduct analyses to understand the net effect on the capacity of their systems.
Force Characteristics of Longitudinally Coupled Slab Track Turnout on Bridges under Temperature Action
Authors: Ren JuanJuan , Xiang Rui , Liu Xueyi
Published: September 2010

With a longitudinally coupled slab track turnout on LeiDa Bridge on the Wuhan–Guangzhou passenger dedicated line in China as an example, an integral finite element model of a turnout (crossover)–slab track–bridge–pier was developed. This model considered two No. 18 welded turnouts with movable frogs in the form of crossover, longitudinally coupled slab track, bridges, and piers as one system. The computational results included the temperature force and the displacement regularity of the turnouts, slab track, bridges, and piers. Their effect parameters, such as the extensional stiffness of the track slab, the friction coefficient of the sliding layer, and the setting of the anchor point, were also investigated. The key findings are that (a) the additional longitudinal forces and the displacement of rails induced by temperature changes increased with reduced slab extensional stiffness, whereas the corresponding forces of the turnout components decreased significantly; (b) the longitudinal distortions of the track structure were insensitive to the failure of the sliding layer but posed negative impacts on the forces and anchor points of the piers; and (c) it was necessary to arrange anchor points on large-span bridges to prevent rail displacement and reduce the negative effects of forces on the piers.
Nondestructive Identification of Freezing-Induced Cracks in Concrete Sleepers of High-Speed Railways in South Korea
Authors: Joh Sung-Ho , Hwang Seon Keun , Kang Tae-Ho , Park Chul-Soo , Lee Il-Wha
Published: September 2010

The construction of a high-speed railway in South Korea was recently impeded by the unexpected problem of cracks in sleepers. These were presumably induced by the volume expansion of freezing water entrapped in the fastening assemblies during the winter. A total of 306,000 sleepers had to be investigated on an urgent basis for hairline cracks and possible latent cracks. These findings suggested that an appropriate nondestructive testing (NDT) technique for the inspection of concrete sleepers should be designed to meet two requirements: speed and reliability in testing. Research was performed to identify an optimal NDT technique by using sleepers with three different crack conditions: without any cracks, with a surface-opening crack, and with a hairline crack and possible latent cracks. Flexural rigidity rather than material stiffness or depth to multiple reflections was chosen as a key parameter for assessment of the structural integrity of a sleeper. The results allowed the design of a two-stage testing procedure: the flexural rigidity assessment of concrete tracks by antisymmetric Lamb (FRACTAL) waves technique for preliminary scanning and spectral analysis of surface waves (SASW) tests for in-depth investigation. A total of 18,177 sleepers that required testing were examined using FRACTAL tests, and 387 of these sleepers were double-checked using SASW tests. Before the overall examination of sleepers, a series of statistical analyses were performed to establish the criteria for defining the quality of a sleeper. The results of the FRACTAL test agreed with those of the SASW test in identifying sleepers with hairline cracks or possible latent cracks.
The azygos anterior cerebral artery bypass: double reimplantation technique for giant anterior communicating artery aneurysms
Authors: Mirzadeh Zaman , Sanai Nader , Lawton Michael T.
Published: September 2010

The authors introduce the azygos anterior cerebral artery (ACA) bypass as an option for revascularizing distal ACA territories, as part of a strategy to trap giant anterior communicating artery (ACoA) aneurysms. In this procedure, the aneurysm is exposed with an orbitozygomatic-pterional craniotomy and distal ACA vessels are exposed with a bifrontal craniotomy. The uninvolved contralateral A2 segment of the ACA serves as a donor vessel for a short radial artery graft. The contralateral pericallosal artery (PcaA) and the callosomarginal artery (CmaA) are connected to the graft in the interhemispheric fissure using the double reimplantation technique. Three anastomoses create an azygos system supplying the entire ACA territory, enabling the surgeon to trap the aneurysm incompletely. Retrograde flow from the CmaA supplies the ipsilateral recurrent artery of Heubner, and the aneurysm lumen thromboses.

The azygos bypass was successfully performed to treat a 47-year-old woman with a giant, thrombotic ACoA aneurysm supplied by the A1 segment of the left ACA, with left PcaA and CmaA originating from the aneurysm base.

The authors conclude that the azygos ACA bypass is a novel option for revascularizing PcaA and CmaA, as part of the overall treatment of giant ACoA aneurysms.
Atypical pituitary adenomas: incidence, clinical characteristics, and implications
Authors: Zada Gabriel , Woodmansee Whitney W. , Ramkissoon Shakti , Amadio Jordan , Nose Vania , Laws Edward R.
Published: September 2010

Object

The 2004 WHO classification of pituitary adenomas now includes an “atypical” variant, defined as follows: MIB-1 proliferative index greater than 3%, excessive p53 immunoreactivity, and increased mitotic activity. The authors review the incidence of this atypical histopathological subtype and its correlation with tumor subtype, invasion, and surgical features.

Methods

The records of 121 consecutive patients who underwent transsphenoidal surgery for pituitary adenomas during an 18-month period were retrospectively reviewed for evidence of atypical adenomas.

Results

Eighteen adenomas (15%) met the criteria for atypical lesions; 17 (94%) of the 18 were macroadenomas. On imaging, 15 (83%) demonstrated imaging evidence of surrounding invasion, compared with 45% of typical adenomas (p = 0.004). Atypical tumors occurred in 12 female (67%) and 6 male (33%) patients. Patient age ranged from 16 to 70 years (mean 48 years). Nine patients (50%) had hormonally active tumors, and 9 had nonfunctional lesions. Four (22%) of the 18 patients presented to us with recurrent tumors. Immunohistochemical analysis demonstrated the following tumor subtypes: GH-secreting adenoma with plurihormonal staining (5 patients [28%]); null-cell adenoma (5 patients [28%]); silent ACTH tumor (3 patients [17%]), ACTH-staining tumor with Cushing's disease (2 patients [11%]), prolactinoma (2 patients [11%]), and silent FSH-staining tumor (1 patient [6%]). The MIB-1 labeling index ranged from 3% to 20% (mean 7%).

Conclusions

Atypical tumors were identified in 15% of resected pituitary adenomas, and they tended to be aggressive, invasive macroadenomas. More longitudinal follow-up is required to determine whether surgical outcomes, potential for recurrence, or metastasis of atypical adenomas vary significantly from their typical counterparts.
Chronic subdural hematoma in the elderly: not a benign disease
Authors: Miranda Lucas Bernardes , Braxton Ernest , Hobbs Joseph , Quigley Matthew R.
Published: September 2010

Object

Chronic subdural hematoma (CSDH) is perceived to be a “benign,” easily treated condition in the elderly, but reported follow-up periods are brief, usually limited to acute hospitalization.

Methods

The authors conducted a retrospective review of data obtained in a prospectively identified consecutive series of adult patients admitted to their institution between September 2000 and February 2008 and in whom there was a CT diagnosis of CSDH. Survival data were compared to life-table data.

Results

Of the 209 cases analyzed, 63% were men and the mean age was 80.6 years (range 65–96 years). Primary surgical interventions performed were bur holes in 21 patients, twist-drill closed-system drainage in 44, and craniotomies in 72. An additional 72 patients were simply observed. Reoperations were recorded in 5 patients—4 who had previously undergone twist-drill drainage and 1 who had previously undergone a bur hole procedure (p = 0.41, chi-square analysis). Thirty-five patients (16.7%) died in hospital, 130 were discharged to rehabilitation or a skilled care facility, and 44 returned home. The follow-up period extended to a maximum of 8.3 years (median 1.45 years). Six-month and 1-year mortality rates were 26.3% and 32%, respectively.

In the multivariate analysis (step-wise logistic regression), the sole factor that predicted in-hospital death was neurological status on admission (OR 2.1, p = 0.02, for each step). Following discharge, the median survival in the remaining cohort was 4.4 years. In the Cox proportional hazards model, only age (hazard ratio [HR] 1.06/year, p = 0.02) and discharge to home (HR 0.24, p = 0.01) were related to survival, whereas the type of intervention, whether surgery was performed, size of subdural hematoma, amount of shift, bilateral subdural hematomas, and anticoagulant agent use did not affect the long- or short-term mortality rate.

Comparison of postdischarge survival and anticipated actuarial survival demonstrated a markedly increased mortality rate in the CSDH group (median survival 4.4 vs 6 years, respectively; HR 1.94, p = 0.0002, log-rank test). This excess mortality rate was also observed at 6 months postdischarge with evidence of normalization only at 1 year.

Conclusions

In this first report of the long-term outcome of elderly patients with CSDH the authors observed persistent excess mortality up to 1 year beyond diagnosis. This belies the notion that CSDH is a benign disease and indicates it is a marker of other underlying chronic diseases similar to hip fracture.
Hubert von Luschka (1820–1875): his life, discoveries, and contributions to our understanding of the nervous system
Authors: Tubbs R. Shane , Vahedi Payman , Loukas Marios , Shoja Mohammadali M. , Cohen-Gadol Aaron A.
Published: September 2010

One of the most prolific anatomical writers of the 19th century, Hubert von Luschka made significant contributions to our knowledge of neuroanatomy. His publications and textbooks were standards for their day. However, very little is written of his life in either the English or the German literature. His name lives on eponymously in more than 20 anatomical structures, including those most relevant to the neurosurgeon, the foramina of Luschka and uncovertebral joints. In this article, the authors discuss the life and contributions of this prominent German surgeon and anatomist.
Reduced Residual Renal Function is Associated with Endothelial Dysfunction in Patients Receiving Peritoneal Dialysis
Authors: Han Seung Hyeok , Lee Sang Choel , Kang Ea Wha , Park Jung Kyung , Yoon Hyang Sook , Yoo Tae-Hyun , Choi Kyu Hun , Han Dae-Suk , Kang Shin-Wook
Published: September 2010

♦Background

Endothelial dysfunction, which contributes to atherosclerosis and arteriosclerosis, commonly accompanies end-stage renal disease (ESRD). However, little is known about the role of residual renal function (RRF) in endothelial protection in ESRD patients. This study aimed to investigate the relationship between endothelial function and RRF in patients undergoing peritoneal dialysis (PD).

♦Methods

This was a cross-sectional study involving 72 prevalent PD patients. Demographic and clinical data were recorded and residual glomerular filtration rate (GFR), Kt/V urea, and serum concentrations of inflammatory markers were measured. Endothelial function was assessed by brachial artery endothelium-dependent vasodilation [flow-mediated dilation (FMD)] to reactive hyperemia following 5 minutes of forearm ischemia.

♦Results

In patients with FMD% above the median value (FMD > 2.41%), residual GFR was significantly higher compared to that in patients with FMD% below the median [1.50 (0 - 9.64) vs 0.48 (0 - 3.89) mL/min/1.73 m 2, P = 0.026]. Correlation analyses revealed that residual GFR (p = 0.381, P = 0.001) and total Kt/V urea (γ= 0.408, P < 0.001) were positively correlated with FMD%, whereas PD duration (γ = -0.351, P = 0.003), high-sensitivity C-reactive protein (p = -0.345, P = 0.003), pulse pressure (γ = -0.341, P = 0.003), and age (γ = -0.403, P < 0.001) were inversely correlated with FMD%. In contrast, there was no correlation between peritoneal Kt/V urea and FMD%. In multivariate linear regression analysis adjusted for these factors, residual GFR was found to be an independent determinant of FMD% (β = 0.317, P = 0.017).

♦ Conclusion

This study shows that RRF is independently associated with endothelial dysfunction in ESRD patients on PD, suggesting that RRF may contribute to endothelial protection in these patients.
RENTAL PRICE CONVERGENCE IN A DEVELOPING ECONOMY: NEW EVIDENCE FROM NONLINEAR PANEL UNIT ROOT TEST
Authors: Bilgin Mehmet Huseyin , Lau Chi Keung Marco , Demir Ender , Astrauskienė Nijolė
Published: September 2010

We examine the hypothesis of nonlinear rental price convergence using relative rental price index of three major cities of Turkey namely, Istanbul, Izmir, and Ankara span from the period from January 1994 to February 2010. Our results indicate that all cities exhibit rental price convergence towards its national mean level for the period of January 1994 to December 2004. In contrast, none of the cities show evidence of convergence from January 2005 to February 2010. The evidence clearly shows rental price divergence in Turkish property market. Santruka Darbe tikrinama triju pagrindiniu Turkijos miestu — Stambulo, Izmiro ir Ankaros — netiesines rentos kainu konvergencijos hipoteze nuo 1994 m. sausio men. iki 2010 m. vasario men., taikant santykini rentos kainu indeksa. Tyrimu rezultatai rodo, kad nuo 1994 m. sausio men. iki 2004 m. gruodžio men. visuose miestuose rentos kainos artejo prie vidutinio nacionalinio lygio. Priešingai, tokios konvergencijos irodymu negauta ne vieno miesto atžvilgiu nuo 2005 m. sausio men. iki 2010 m. vasario men. Faktai aiškiai rodo Turkijos nekilnojamojo turto rinkos rentos kainu divergencija.
REAL ESTATE'S KNOWLEDGE AND DEVICE‐BASED DECISION SUPPORT SYSTEM
Authors: Zavadskas Edmundas Kazimieras , Kaklauskas Artūras , Banaitis Audrius
Published: September 2010

The authors of this paper participated in the European Union's Sixth Framework Programme project Intelligent Cities (INTELCITIES, 2005). One of INTELCITIES's goals (on the Lithuanian side) was to develop a Real Estate's Knowledge and Device‐based Decision Support System (KDDSS‐RE). Major KDDSS ‐RE functions include creating and maintaining customer's personalized real estate objectives, preferences, and evaluation criteria; participation of various stakeholders (buyers, sellers, brokers, etc.) in joint determination of criteria (criteria system, values and weights) defining real estate; market signalling, provide device‐based data about indoor microclimates and allergens causing allergy in buildings; searching for real estate alternatives, finding alternatives and making an initial negotiation table, completing a multiple criteria analysis of alternatives, making electronic negotiations based on real calculations, determining the most rational real estate purchase variant, and completing an analysis of loan alternatives offered by certain banks. The authors of the present research have suggested the idea to integrate knowledge‐based, devices‐based and decision support systems. In order to demonstrate the integration decision support, knowledge and devices systems in the real estate sector a Real Estate's Knowledge and Devices‐based Decision Support System have been considered in the paper as an example. Santruka Šio darbo autoriai dalyvavo šeštosios bendrosios programos projekte ‘Intelektualūs miestai” (INTELCITIES). Vienas iš INTELCITIES tikslu (Lietuvoje) – sukurti žiniomis ir prietaisais pagrista nekilnojamojo turto sprendimu paramos sistema (KDDSS‐RE). Pagrindines KDDSS‐RE funkcijos yra šios: sukurti ir pletoti klientui asmeniškai pritaikytus nekilnojamojo turto tikslus, pageidavimus ir vertinimo kriterijus; ivairioms suinteresuotosioms grupems (pirkejams, pardavejams, tarpininkams ir pan.) suteikti galimybe drauge nustatyti nekilnojamaji turta apibūdinančius kriterijus (kriteriju sistema, vertes ir reikšmingumus); rinkos tyrimas, iš prietaisu gautu duomenu apie patalpu mikroklimata ir pastatuose esančius alergenus pateikimas; alternatyviu nekilnojamojo turto variantu paieška, ju radimas ir pradines derybu lenteles sudarymas, alternatyvu daugiakriterine analize, realiais skaičiavimais pagristos elektronines derybos, racionaliausio nekilnojamojo turto varianto pirkimui nustatymas ir tam tikru banku siūlomu alternatyviu paskolu variantu analize. Šio tyrimo autoriai pasiūle ideja integruoti žiniomis ir prietaisais pagristas bei sprendimu paramos sistemas. Siekiant sprendimu paramos, žiniu ir prietaisu sistemu integravima pademonstruoti nekilnojamojo turto sektoriuje, darbe nagrinejama žiniomis ir prietaisais pagrista nekilnojamojo turto sprendimu paramos sistema.
THE FEELINGS OF CONSUMER GUILT: A PHENOMENOLOGICAL EXPLORATION
Authors: Dedeoğlu Ayla Özhan , Kazançoğlu İpek
Published: September 2010

Guilt, a discomforting, yet widespread emotion, has been frequently exploited by advertisers. Despite all of the great deal of research effort, there remains a dearth of research that examines the dimensions of consumer guilt by providing a more complete understanding. The present study represents an attempt to develop a phenomenological account of consumer guilt and broaden the understanding of the dimensions and dynamics of consumer guilt grounded in consumers’ lived experiences by using in‐depth interviews and projective data. Regarding this, a thorough analysis revealed the existence of five dimensions of consumer guilt, namely, hesitation, sadness, reluctance to spend, regret and self‐blame. Consumer guilt is felt due to transgressions, self‐control failures and indulgence in hedonistic desires. The findings show that guilt feelings are found to be cyclic, short‐lived and superficial and mostly arise as a result of good and bad actions but not always of right versus wrong actions. In the consumption society, guilt is attached to new concerns brought about by cultural drift. Santrauka Kalte ir neramumas - labai paplitusi emocine būsena, kuria dažnai nagrineja reklamos specialistai. Nepaisant to, kad apskritai yra atlikta daugybe tyrimu, vis dar trūksta vartotojo kaltes aspektus analizuojančiu tyrimu, kurie padetu geriau suvokti šia problema. Šiame tyrime buvo stengiamasi išpletoti vartotojo kaltes fenomenologija ir praplesti suvokimo ribas apie vartotoju kaltes matmenis ir dinamika, grindžiama vartotojo išgyventa patirtimi, naudojant nuodugnia apklausa ir projektine informacija. Atlikus visapusiška analize, paaiškejo, kad egzistuoja penki vartotojo kaltes matmenys: neryžtingumas, liūdesys, nenoras išlaidauti, apgailestavimas, saves kaltinimas. Vartotojas jaučia kalte del prasižengimo, savikontroles praradimo, piktnaudžiavimo, tenkinant hedonistinius troškimus. Rezultatai parode, kad kaltes jausmas yra cikliškas, trumpalaikis ir paviršutiniškas, dažniausiai kylantis kaip gero ar blogo veiksmo rezultatas. Vartotojiškoje visuomeneje kalte yra siejama su del kultūros poslinkio atsiradusiais naujais rūpesčiais.
TIME‐VARYING VOLATILITY MODELLING OF BALTIC STOCK MARKETS
Authors: Aktan Bora , Korsakienė Renata , Smaliukienė Rasa
Published: September 2010

As time‐varying volatility has found applications in roughly all time series modelling in economics, it largely draws attention in the areas of financial markets. This study also examines the characteristics of conditional volatility in the Baltic Stock Markets (Estonia, Latvia and Lithuania) by using a broad range of GARCH volatility models. Correctly forecasting the volatility leads to better understanding and managing financial market risk. Daily returns from four Baltic stock indexes are used; Estonia (TALSE index), Latvia (RIGSE index), Lithuania (VILSE index) and synthetic BALTIC benchmark index. We test a large family of GARCH models, including; the basic GARCH model, GARCH‐in‐mean model, asymmetric exponential GARCH and GJR GARCH, power GARCH and component GARCH model. We find strong evidence that daily returns from Baltic Stock Markets can be successfully modelled by GARCH‐type models. For all Baltic markets, we conclude that increased risk will not necessarily lead to a rise in the returns. All of the analysed indexes exhibit complex time series characteristics involving asymmetry, long tails and complex autoregression in the returns. Results from this study are firmly recommended to financial officers and international investors. Santrauka Straipsnyje analizuojamas salyginis Baltijos vertybiniu popieriu rinku (Estijos, Latvijos ir Lietuvos) nepastovumas, taikant eile GARCH kintamumo modeliu. Pažymetina, kad tinkamai prognozuojant nepastovuma, galima geriau suvokti ir valdyti finansiniu rinku rizika. Straipsnyje remiamasi keturiu Baltijos šaliu kasdienemis akciju indeksu gražomis; Estijos (TALSE indeksu), Latvijos (RIGSE indeksu), Lietuvos (VILSE indeksu) ir sintetiniu palyginamuoju BALTIC indeksu. Pritaikius eile GARCH kintamumo modeliu, galima teigti, kad didejanti rizika Baltijos šaliu rinkose nebūtinai itakos vertybiniu popieriu gražos augima. Tyrimo metu gauti rezultatai rekomenduojami finansu specialistams ir investuotojams.
Analysis of the human intestinal epithelial cell transcriptional response to Lactobacillus acidophilus, Lactobacillus salivarius, Bifidobacterium lactis and Escherichia coli
Authors: Putaala H. , Barrangou R. , Leyer G. , Ouwehand A. , Hansen E. Bech , Romero D. , Rautonen N.
Published: September 2010

The complex microbial population residing in the human gastrointestinal tract consists of commensal, potential pathogenic and beneficial species, which are probably perceived differently by the host and consequently could be expected to trigger specific transcriptional responses. Here, we provide a comparative analysis of the global in vitro transcriptional response of human intestinal epithelial cells to Lactobacillus acidophilus NCFM™, Lactobacillus salivarius Ls-33, Bifidobacterium animalis subsp. lactis 420, and enterohaemorrhagic Escherichia coli O157:H7 (EHEC). Interestingly, L. salivarius Ls-33 DCE-induced changes were overall more similar to those of B. lactis 420 than to L. acidophilus NCFM™, which is consistent with previously observed in vivo immunomodulation properties. In the gene ontology and pathway analyses both specific and unspecific changes were observed. Common to all was the regulation of apoptosis and adipogenesis, and lipid-metabolism related regulation by the probiotics. Specific changes such as regulation of cell-cell adhesion by B. lactis 420, superoxide metabolism by L. salivarius Ls-33, and regulation of MAPK pathway by L. acidophilus NCFM™ were noted. Furthermore, fundamental differences were observed between the pathogenic and probiotic treatments in the Toll-like receptor pathway, especially for adapter molecules with a lowered level of transcriptional activation of MyD88, TRIF, IRAK1 and TRAF6 by probiotics compared to EHEC. The results in this study provide insights into the relationship between probiotics and human intestinal epithelial cells, notably with regard to strain-specific responses, and highlight the differences between transcriptional responses to pathogenic and probiotic bacteria.
Antibiotic resistance in faecal microbiota of Greek healthy infants
Authors: Mitsou E. , Kirtzalidou E. , Pramateftaki P. , Kyriacou A.
Published: September 2010

Increasing use of antibiotics for the treatment of infectious diseases and also for non-therapeutic reasons (agriculture, animal husbandry and aquaculture) has led to the increasing incidence of antibiotic resistance and the ineffectiveness of antimicrobial treatment. Commensal intestinal bacteria are very often exposed to the selective pressure of antimicrobial agents and may constitute a reservoir of antibiotic resistance determinants that can be transferred to pathogens. The present study aimed to investigate the antibiotic susceptibility profile and the presence of selected resistance genes in cocci isolated from the faecal microbiota of 35 healthy, full-term infants at 4, 30 and 90 days after delivery. A total of 148 gram-positive, catalase-negative cocci were isolated and tested for susceptibility to 12 different antibiotics by disk-diffusion technique. Multiplex PCR analysis was performed for the identification of Enterococcus spp. isolates and the simultaneous detection of vancomycin-resistance genes. PCR-based methodology was used also for identification of tetracycline and erythromycin resistance determinants. Identification results indicated E. faecalis as the predominant species (81 strains), followed by E. faecium, E. casseliflavus/E. flavescens and E. gallinarum. High prevalence of resistance to tetracycline (39.9%), erythromycin (35.1%), vancomycin (19.6%) and to nucleic acid synthesis inhibitors was detected. PCR data revealed 24 out of 52 erythromycin-resistant isolates carrying the ermB gene and 32 out of 59 tetracycline-resistant strains carrying tet genes, with tet(L) determinant being the most frequently detected. Only intrinsic vancomycin resistance (vanC1 and vanC2/C3) was reported among tested isolates. In conclusion, erythromycin and tetracycline acquired resistant traits are widespread among faecal cocci isolates from Greek, healthy infants under no apparent antimicrobial selective pressure.
Homeostatic impact of indigenous microbiota and secretory immunity
Authors: Brandtzaeg P.
Published: September 2010

In the process of evolution, the mucosal immune system has generated two layers of anti-inflammatory defence: (1) immune exclusion performed by secretory IgA (and secretory IgM) antibodies to modulate or inhibit surface colonisation of microorganisms and dampen penetration of potentially dangerous antigens; and (2) suppressive mechanisms to avoid local and peripheral hypersensitivity to innocuous antigens, particularly food proteins and components of commensal bacteria. When induced via the gut, the latter phenomenon is called 'oral tolerance', which mainly depends on the development of regulatory T (Treg) cells in mesenteric lymph nodes to which mucosal dendritic cells (DCs) carry exogenous antigens and become conditioned for induction of Treg cells. Mucosally induced tolerance appears to be a rather robust adaptive immune function in view of the fact that large amounts of food proteins pass through the gut, while overt and persistent food allergy is not so common. DCs are 'decision makers' in the immune system when they perform their antigen-presenting function, thus linking innate and adaptive immunity by sensing the exogenous mucosal impact (e.g. conserved microbial molecular patterns). A balanced indigenous microbiota is required to drive the normal development of both mucosa-associated lymphoid tissue, the epithelial barrier with its secretory IgA (and IgM) system, and mucosally induced tolerance mechanisms including the generation of Treg cells. Notably, polymeric Ig receptor (pIgR/SC) knock-out mice that lack secretory IgA and IgM antibodies show reduced epithelial barrier function and increased uptake of antigens from food and commensal bacteria. They therefore have a hyper-reactive immune system and show predisposition for systemic anaphylaxis after sensitisation; but this development is counteracted by enhanced oral tolerance induction as a homeostatic back-up mechanism.
Characterisation of Lactobacillus helveticus strains producing antihypertensive peptides by RAPD and inverse-PCR of IS elements
Authors: Aquilanti L. , Carbini A. , Strappati R. , Santarelli S. , Silvestri G. , Garofalo C. , Clementi F.
Published: September 2010

Lactobacillus helveticus is used for the manufacture of cheeses and milk-based products. Although it is not considered a probiotic microorganism, some strains demonstrated beneficial effects through the production of antihypertensive peptides from the hydrolysis of casein during milk fermentation. Strain-specificity of bioactive peptide production by L. helveticus makes the availability of reliable typing methods essential for both legal and good manufacturing processes. Accordingly, RAPD and inverse-PCR of five insertion sequence elements were comparatively evaluated for the molecular characterisation of four L. helveticus dairy cultures producing antihypertensive peptides and fourteen reference strains. Calculation of discriminatory indices and cluster analysis of the DNA fingerprints confirmed the suitability of both approaches for acceptable strain differentiation. Although RAPD was more discriminating, for a few test strains a neat discrimination was only achieved through multiplex inverse-PCR, thus suggesting the suitability of a combined analytical approach for a finer strain discrimination.
On spurious instabilities on the β-planes with no mean flows
Authors: Paldor N.
Published: September 2010

Abstract. Recent numerical calculations that suggest the existence of instabilities of the shallow water equations on the β-planes (both mid-latitudes and on the equator) are shown to be associated with spurious instabilities rather than genuine unstable modes. The spurious unstable modes arise in an analysis of the necessary condition for the existence of complex roots to the cubic dispersion relation but it is shown here that these complex roots are not associated with solutions (eigenvalues and eigenfunctions) of the corresponding eigenvalue equation.
The influence of leaf photosynthetic efficiency and stomatal closure on canopy carbon uptake and evapotranspiration – a model study in wheat and sugar beet
Authors: Schickling A. , Graf A. , Pieruschka R. , Plückers C. , Geiß H. , Lai I.-L. , Schween J. H. , Erentok K. , Schmidt M. , Wahner A. , Crewell S. , Rascher U.
Published: September 2010

Abstract. In this study two crop species, winter wheat (Triticum aestivum) and sugar beet (Beta vulgaris), were monitored over the course of five days during the entire season. We investigated the link of the main physiological leaf-level mechanisms, stomatal conductance and efficiency of photosynthetic energy conversion on canopy transpiration and photosynthetic CO2 uptake. The physiological status of 900 leaves of different plants in a natural canopy was characterized on the leaf level using chlorophyll fluorescence. Gas exchange measurements were performed at leaves of 12 individual plants of each species. Eddy covariance flux measurements provided information on CO2, water and energy fluxes on the field scale. The diurnal pattern of stomatal resistance on the leaf level was especially for sugar beet similar to the canopy resistance, which indicates that stomatal resistance may have a large impact on the bulk canopy resistance. The diurnal changes in canopy resistance appeared to have less effect on the evapotranspiration, which was mainly dependent on the amount of incoming radiation. The similar diurnal pattern of water use efficiency on the leaf level and on the canopy level during the day, underline the influence of physiological mechanisms of leaves on the canopy. The greatest difference between water use efficiency on leaf and canopy occurred in the morning, mainly due to an increase of stomatal resistance. Limitation of CO2 uptake occurred in the afternoon when water vapor pressure deficit increased. Maxima of net ecosystem productivity corresponded to the highest values of photosynthetic capacity of single leaves, which occurred before solar noon. Within the course of a few hours, photosynthetic efficiency and stomatal resistance of leaves varied and these variations were the reason for diurnal variations in the carbon fluxes of the whole field. During the seasonal development, the leaf area index was the main factor driving carbon and water exchange, when both crops were still growing. During senescence of winter wheat these structural parameters did not account for changes in canopy fluxes and remaining high green leaf material of sugar beet did not present the reduction in canopy fluxes due to beginning dormancy. We thus hypothesize that the functional status of plants is also important to correctly predict carbon and water fluxes throughout the season. We propose to additionally include the physiological status of plants in carbon flux models in order to improve the quality of the simulation of diurnal patterns of carbon fluxes.
Nordic Seas nutrients data in CARINA
Authors: Olafsson J. , Olsen A.
Published: September 2010

Abstract. Water column data of carbon and carbon relevant hydrographic and hydrochemical parameters from 188 cruises in the Arctic, Atlantic, and Southern Ocean have been assembled and the collection merged into a new database: CARINA (CARbon IN the Atlantic). The data have been subject to rigorous quality control (QC) in order to ensure highest possible quality and consistency. The data for most of the parameters included were examined in order to quantify systematic biases in the reported values, i.e. secondary quality control. Significant biases have been corrected for in the data products, i.e. the three merged files with measured, calculated and interpolated values for each of the three CARINA regions; the Arctic Mediterranean Seas (AMS), the Atlantic (ATL) and the Southern Ocean (SO). With the adjustments, the CARINA database is consistent both internally as well as with GLODAP (Key et al., 2004) and is suitable for accurate assessments of, for example, oceanic carbon inventories and uptake rates, and for model validation. The Arctic Mediterranean Seas is the collective term for the Arctic Ocean and the Nordic Seas, and the quality control was carried out separately in these two areas. This contribution presents an account of the quality control of the nutrients (nitrate, phosphate, and silicate) data from the Nordic Seas in CARINA. Out of the 35 cruises from the Nordic Seas included in CARINA, 33 had nutrients data. The nitrate data from 4 of these appeared to be of so poor quality that they should not be used, for phosphate this number is 7 and for silicate it is 3. We also recommend that the nitrate data from 4 of the cruises should be adjusted, for phosphate and silicate only data from one cruise should be adjusted. The final data appears consistent to 5% based on evaluation of deep data. For nitrate this corresponds to 0.6 μmol kg−1, and for phosphate and silicate it corresponds to 0.04 and 0.6 μmol kg−1, respectively.
An approach to the implementation of European Directive 2007/60/EC on flood risk management in the Czech Republic
Authors: Dráb A. , Říha J.
Published: September 2010

Abstract. Directive 2007/60/EC of the European Parliament and of the Council of 23 October 2007 on the assessment and management of flood risks (the Flood Risk Directive) signifies that flood risk analysis methods are gaining ground in EC Member States and, therefore, also in the Czech Republic (CR). Procedures of flood risk analysis have been developed in the Czech Republic since the catastrophic floods of 1997 in line with European and worldwide trends and have been tested and applied in hundreds of case studies to date. Currently, the Flood Risk Directive Guideline based on past experience with flood risk analysis applications is being processed. The aim of the paper is to present flood risk analysis procedures and specially developed techniques for the assembly of flood hazard, danger and flood risk maps. Methods related to flood risk management plans are briefly mentioned as well. The following particular problems are discussed in more detail: an application and extension of the "danger matrix" approach, the definition of residual danger, the formulation of efficiency criteria and preliminary multi-criteria flood risk assessment. These issues were tested in practical applications at pilot locations in the Czech Republic. Present experience provides evidence that the flood risk analysis methods used in the Czech Republic are in harmony with the requirements of the Flood Risk Directive. The proposed and applied methods are based primarily on existing available data such as flood extent maps, cadastral maps, the Register of Census Districts and Structures and others.
Implementing Telerehabilitation Research For Stroke Rehabilitation With Community Dwelling Veterans: Lessons Learned
Authors: Chumbler Neale R , Quigley Patricia , Sanford Jon , Griffiths Patricia , Rose Dorian , Morey Miriam , Ely E. Wesley , Hoenig Helen
Published: September 2010

Telerehabilitation (TR) is the use of telehealth technologies to provide distance support, rehabilitation services and information exchange between people with disabilities and their clinical providers. This article discusses the barriers experienced when implementing a TR multi-site randomized controlled trial for stroke patients in their homes, and the lessons learned from conducting the study. The barriers are divided into two sections: those specific to TR and those pertinent to research overall. The TR specific barriers included the rapidly changing telecommunications and health care environment and inconsistent equipment functionality. The barriers applicable to research overall included the need for telehealth research to meet regulations in diverse departments and the rapidly expanding and changing research regulations. Solutions to the barriers included having various telehealth equipment available to allow for functionality with the currently diverse telecommunications infrastructure, rigorous pilot testing all equipment in different situations, and having biomedical engineering staff on-call and on-site.
Telerehabilitation in Scotland: Current Initiatives and Recommendations for Future Development
Authors: Hill Anne
Published: September 2010

Rehabilitation services are set to become central to modern health care systems as they strive to support an increasingly ageing population to live as independently as possible, while maintaining quality services. Alternative service delivery options such as telerehabilitation may assist in meeting the growing demand for services and many countries are exploring the potential use of telerehabilitation within their health care systems. The Scottish Centre for Telehealth commissioned an independent scoping study and subsequent report into the potential development and realisation of telerehabilitation services across Scotland. The scope of the report was restricted to adult rehabilitation services and aimed to identify opportunities for the use of telerehabilitation and to recommend clear and achievable steps towards implementation of telerehabilitation. This article outlines some of the telerehabilitation initiatives currently underway in Scotland and discusses some of the key recommendations made in the report to the Scottish Centre for Telehealth for the future advancement and application of telerehabilitation across Scotland.
Processing Porous Bulk Metallic Glass Using Prealloyed Powders
Authors: Liu Yong , Zhu Yitian , Li Fei , Yan Wei
Published: September 2010

Zr50Cu40Al10 metallic‐glass powders are prepared via the gas‐atomization method. The powders are spherical in shape, and contain different crystalline phases depending on the particle size. Through mechanical milling, the shape and the structure of the as‐atomized metallic‐glass powders can be modified, and very‐fine and fully amorphous powders are obtained after milling for 120 h. The as‐milled powders show excellent compressibility and densification behavior. By the addition of the Cu powders and using the as‐milled metallic‐glass powders, a porous metallic‐glass compact is fabricated, which has a porosity of about 48% and a pronounced ductility.
Bioreactors in Tissue Engineering
Authors: Dermenoudis Stergios , Missirlis Yannis F.
Published: September 2010

Tissue engineering is a promising interdisciplinary scientific field of regenerative medicine. Aiming at the structural and functional restoration of damaged tissues and organs, it possesses a role of significant socioeconomical impact. In the course towards the ultimate goal of artificially constructed natural organs, our knowledge of the elementary constitutive components of living organisms and the intrinsic mechanisms that drive their interactions is greatly enhanced. Bioreactors are valuable tools providing the technological means to investigate fundamental issues for basic research and to improve tissue‐engineering products for clinical applications. They are devices enabling the in vitro simulation of the in vivo biological, physical and mechanical environment of growing tissues. In this review paper, we discuss the general demands defining the design considerations for modern bioreactor systems. These criteria originate from physiological characteristics of the cells and biochemical and mechanical properties of the extracellular matrix (ECM). In this context, we present an overview of the various bioreactor systems dedicated to the study of specific functional tissues developed by numerous research groups.
A Microbial‐Mineralization‐Inspired Approach for Synthesis of Manganese Oxide Nanostructures with Controlled Oxidation States and Morphologies
Authors: Oba Manabu , Oaki Yuya , Imai Hiroaki
Published: September 2010

Manganese oxide nanostructures are synthesized by a route inspired by microbial mineralization in nature. The combination of organic molecules, which include antioxidizing and chelating agents, facilitates the parallel control of oxidation states and morphologies in an aqueous solution at room temperature. Divalent manganese hydroxide (Mn(OH)2) is selectively obtained as a stable dried powder by using a combination of ascorbic acid as an antioxidizing agent and other organic molecules with the ability to chelate to manganese ions. The topotactic oxidation of the resultant Mn(OH)2leads to the selective formation of trivalent manganese oxyhydroxide (β‐MnOOH) and trivalent/tetravalent sodium manganese oxide (birnessite, Na0.55Mn2O4·1.5H2O). For microbial mineralization in nature, similar synthetic routes via intermediates have been proposed in earlier works. Therefore, these synthetic routes, which include in the present study the parallel control over oxidation states and morphologies of manganese oxides, can be regarded as new biomimetic routes for synthesis of transition metal oxide nanostructures. As a potential application, it is demonstrated that the resultant β‐MnOOH nanostructures perform as a cathode material for lithium ion batteries.