bluuebunny/crossref_metadata_2025 huggingface dataset:
Pharmacokinetics of dexmedetomidine during administration of vatinoxan in male neutered cats anesthetized with isoflurane
Authors: Pypendop Bruno H. , Ahokoivu Hanna , Honkavaara Juhana
Published: July 2019

Dexmedetomidine is an alpha‐2 adrenoceptor agonist, and vatinoxan is an alpha‐2 antagonist believed to poorly cross the blood–brain barrier in cats. Dexmedetomidine–vatinoxan combinations are of interest in anesthetized cats because the anesthetic sparing effect of dexmedetomidine may be preserved while vatinoxan attenuates the adverse cardiovascular effects of dexmedetomidine. The aim of this study was to characterize the pharmacokinetics of dexmedetomidine in cats during administration of isoflurane and vatinoxan. Six healthy adult male castrated cats were anesthetized with isoflurane in oxygen. Vatinoxan was administered using a target‐controlled infusion system intended to maintain a plasma concentration of 4 µg/ml. Dexmedetomidine, 35 µg/kg was administered intravenously over 5 min. Plasma dexmedetomidine and vatinoxan concentrations were measured at selected time points ranging from prior to 8 hr after dexmedetomidine administration using liquid chromatography/tandem mass spectrometry. Compartment models were fitted to the time‐concentration data using nonlinear mixed‐effect modeling. A three‐compartment model best fitted the data. Typical value (% interindividual variability) for the three‐compartment volumes (ml/kg), the metabolic clearance and the two intercompartment distribution clearances (ml min−1kg−1) were 168 (259), 318 (35), 1,425 (18), 12.4 (31), 39.1 (18), and 29.6 (17), respectively. Mean ± standard deviation plasma vatinoxan concentration was 2.6 ± 0.6 µg/ml.
Rice black‐streaked dwarf virus‐encoded P5‐1 regulates the ubiquitination activity of SCF E3 ligases and inhibits jasmonate signaling to benefit its infection in rice
Authors: He Long , Chen Xuan , Yang Jin , Zhang Tianye , Li Juan , Zhang Songbai , Zhong Kaili , Zhang Hengmu , Chen Jianping , Yang Jian
Published: July 2019

SCF (Skp1/Cullin1/F‐box) complexes are key regulators of many cellular processes. Viruses encode specific factors to interfere with or hijack these complexes and ensure their infection in plants. The molecular mechanisms controlling this interference/hijack are currently largely unknown.

Here, we present evidence of a novel strategy used by Rice black‐streaked dwarf virus (RBSDV) to regulate ubiquitination in rice (Oryza sativa) by interfering in the activity of OsCSN5A. We also show that RBSDV P5‐1 specifically affects CSN‐mediated deRUBylation of OsCUL1, compromising the integrity of the SCFCOI1 complex.

We demonstrate that the expressions of jasmonate (JA) biosynthesis‐associated genes are not inhibited, whereas the expressions of JA‐responsive genes are down‐regulated in transgenic P5‐1 plants. More importantly, application of JA to P5‐1 transgenic plants did not reduce their susceptibility to RBSDV infection.

Our results suggest that P5‐1 inhibits the ubiquitination activity of SCF E3 ligases through an interaction with OsCSN5A, and hinders the RUBylation/deRUBylation of CUL1, leading to an inhibition of the JA response pathway and an enhancement of RBSDV infection in rice.
The challenge for global health systems in preventing and managing obesity
Authors: Wolfenden Luke , Ezzati Majid , Larijani Bagher , Dietz William
Published: July 2019

Few health crises have been as predictable as the unfolding obesity pandemic. Clinical and public health services remain the front line of efforts to reduce the burden of obesity. While a range of clinical practice guidelines exist, the need for clinical interventions exceeds the capacity of health systems to provide care for those affected with obesity, and routine clinical practices fall far short of guidelines recommendations even in high‐income countries. In this manuscript, we discuss current recommendations regarding obesity interventions and key challenges facing global health systems in managing the health needs of people with obesity. Improving the provision of obesity‐related health care is a considerable challenge and will require changing existing perceptions of obesity as a matter of personal failure to its recognition as a disease, innovative approaches to health system reform, clinician capacity building and implementation support, a focus on prevention, and wise resource allocation. Leadership from governments, the medical profession, and patient and community groups to address the issues raised in this manuscript is urgently needed to address the growing health concern.
BIA‐Obesity (Business Impact Assessment—Obesity and population‐level nutrition): A tool and process to assess food company policies and commitments related to obesity prevention and population nutrition at the national level
Authors: Sacks Gary , Vanderlee Lana , Robinson Ella , Vandevijvere Stefanie , Cameron Adrian J. , Ni Mhurchu Cliona , Lee Amanda , Ng See Hoe , Karupaiah Tilakavati , Vergeer Laura , L'Abbé Mary , Swinburn Boyd
Published: July 2019

Addressing obesity and improving the diets of populations requires a comprehensive societal response. The need for broad‐based action has led to a focus on accountability of the key factors that influence food environments, including the food and beverage industry. This paper describes the Business Impact Assessment—Obesity and population‐level nutrition (BIA‐Obesity) tool and process for benchmarking food and beverage company policies and practices related to obesity and population‐level nutrition at the national level. The methods for BIA‐Obesity draw largely from relevant components of the Access to Nutrition Index (ATNI), with specific assessment criteria developed for food and nonalcoholic beverage manufacturers, supermarkets, and chain restaurants, based on international recommendations and evidence of best practices related to each sector. The process for implementing the BIA‐Obesity tool involves independent civil society organisations selecting the most prominent food and beverage companies in each country, engaging with the companies to understand their policies and practices, and assessing each company's policies and practices across six domains. The domains include: “corporate strategy,” “product formulation,” “nutrition labelling,” “product and brand promotion,” “product accessibility,” and “relationships with other organisations.” Assessment of company policies is based on their level of transparency, comprehensiveness, and specificity, with reference to best practice.
Central Sensitization Inventory Mediates the Relationship Between Inflammatory Bowel Disease Activity and Worse Musculoskeletal Pain Experiences
Authors: Falling Carrie L. , Stebbings Simon , Baxter David G. , Gearry Richard B. , Mani Ramakrishnan
Published: July 2019

Background

Musculoskeletal conditions are well documented in inflammatory bowel disease (IBD). However, whether IBD activity influences musculoskeletal pain experiences is uncertain. Central sensitization has been proposed in patients with IBD who are suffering from persistent pain. Identification of central sensitization symptomology using the Central Sensitization Inventory (CSI) has been reported in many pain‐related disorders. Aims of this study were to explore predictive relationships between IBD activity and musculoskeletal pain experiences (severity/interference), and the mediating effects of the CSI.

Methods

A cross‐sectional online survey was performed exploring self‐reported musculoskeletal pain in adults with IBD. Survey questionnaires included IBD activity indices, numeric rating scales, PROMIS Pain Interference, and the CSI. Linear regression was used to examine the relationship between active IBD and pain experiences. Simple and serial mediation analyses were used to explore mediation models: independent variable (IBD activity), dependent variables (severity/interference), and mediators (CSI/severity).

Results

208 adults with IBD, 18 to 88 years of age, reported musculoskeletal pain. Regression analysis identified IBD activity as a significant predictor of worse pain severity (R2 = 0.039, P < 0.005) and interference (R2 = 0.067, P < 0.001). Simple mediation showed a significant indirect effect from CSI scores between IBD activity and pain severity. Serial mediation analysis showed a significant indirect effect from CSI scores and pain severity, between IBD activity and pain interference.

Conclusion

Active IBD demonstrated a positive association with worse musculoskeletal pain experiences. The CSI demonstrated significant mediation between active IBD and pain severity. Additionally, the CSI and pain severity demonstrated significant mediation between active IBD and pain interference. This suggests that symptoms of central sensitization significantly influence musculoskeletal pain experiences in IBD.
How is the term haemangioma used in the literature? An evaluation against the revised ISSVA classification
Authors: Steele Lloyd , Zbeidy Sarah , Thomson Jason , Flohr Carsten
Published: July 2019

Background/objectives

The International Society for the Study of Vascular Anomalies (ISSVA) classification separates vascular anomalies into vascular malformations and vascular tumors. However, misdiagnoses and misperceptions still persist around the use of the term “hemangioma.” We assessed whether the term “haemangioma” (British spelling) was used as part of ISSVA terminology in the literature.

Methods

We searched PubMed for all English‐language publications containing the British spelling “haemangioma” in the title or abstract from January 1, 2015 to December 31, 2016. Each paper was judged by two independent reviewers, with conflicts resolved by senior review.

Results

By the standard of the 2014 ISSVA classification, 126/195 (64.6%) publications used incorrect terminology for vascular anomalies. This was reduced to 118/195 (60.5%) when using the 2018 ISSVA classification. The most commonly misused terms were cavernous haemangioma (27.1%), haemangioma without further specification (26.3%), and hepatic/liver haemangioma (12.7%). Age was a significant predictor of accuracy of terminology (P = 0.01), with a higher accuracy in children. Correct usage also varied by the site of the vascular anomaly, being highest for lesions of the skin (76.5%) followed by muscle (58.3%), soft tissue (23.5%), bone (21.4%), viscera (7.7%), and eye (0.0%) (P = 0.02).

Conclusions

The term “haemangioma” is frequently used incorrectly by the standards of the 2014 and 2018 ISSVA classifications. Correct terminology is important as the natural history and treatment options vary depending on the type of vascular anomaly.
The Challenge of Social Media Incorporation: A Case Study of HACAN Clearskies
Authors: Rowe Andrew D. , Pitfield David E.
Published: July 2019

Social media can pose challenges to campaign group strategy, especially for existing campaign groups who incorporate social media into their campaigns. This article uses social network analysis to explore how social media is used by the anti‐airport expansion group, HACAN Clearskies (HACAN Clearskies is an acronym for the Heathrow Association for the Control of Aircraft Noise). Social media data were obtained using NodeXL and Twitonomy. As a result of questions raised in these findings, interviews with the social media coordinator of HACAN Clearskies were conducted. The results show the utilization of social media as an information dissemination platform and how a social media reluctant membership base prevents them from organizing mass protest through social media. The implications of these results are also discussed in relation to future social media practice.

Related Articles

Cormack, Lindsey. 2019. “Leveraging Peer‐to‐Peer Connections to Increase Voter Participation in Local Elections.”Politics & Policy47 (2): 248‐266.https://doi.org/10.1111/polp.12297

Pompl, Solange, and Sergiu Gherghina. 2019. “Messages and Familiar Faces: Crowdfunding in the 2017 U.K. Electoral Campaign.”Politics & Policy47.https://doi.org/10.1111/polp.12301
Alpha‐band desynchronization reflects memory‐specific processes during visual change detection
Authors: Erickson Molly A. , Smith Dillon , Albrecht Matthew A. , Silverstein Steven
Published: July 2019

Recent work investigating physiological mechanisms of working memory (WM) has revealed that modulation of alpha and beta frequency bands within the EEG plays a key role in WM storage. However, the nature of that role is unclear. In the present study, we examined event‐related desynchronization of alpha and beta (α/β‐ERD) elicited by visual tasks with and without a memory component to measure the impact of a WM demand on this electrophysiological marker. We recorded EEG from 60 healthy participants while they completed three variants on a typical change detection task: one in which participants passively viewed the sample array, passive (WM−); one in which participants viewed and attended the sample array in search of a target color but did not memorize the colors, active (WM−); and one in which participants encoded, attended to, and memorized the sample array, active (WM+). Replicating previous findings, we found that active (WM+) elicited robust α/β‐ERD in frontal and posterior electrode clusters and that α‐ERD was significantly associated with WM capacity. By contrast, α/β‐ERD was significantly smaller in the passive (WM−) and active (WM−) tasks, which did not consistently differ from one another. Furthermore, no such relationship was observed between WM capacity and desynchronization in the passive (WM−) or active (WM−) tasks. Taken together, these results suggest that α‐ERD during memory formation reflects a memory‐specific process such as consolidation or maintenance, rather than serving a generalized role in perceptual gating or engagement of attention.
Ensemble Prediction of Time-to-Event Outcomes with Competing Risks: A Case-Study of Surgical Complications in Crohn's Disease
Authors: Sachs Michael C. , Discacciati Andrea , Everhov Åsa H. , Olén Ola , Gabriel Erin E.
Published: July 2019

We develop a novel algorithm to predict the occurrence of major abdominal surgery within 5 years following Crohn's disease diagnosis by using a panel of 29 baseline covariates from the Swedish population registers. We model pseudo-observations based on the Aalen–Johansen estimator of the cause-specific cumulative incidence with an ensemble of modern machine learning approaches. Pseudo-observation preprocessing easily extends all existing or new machine learning procedures for continuous data to right-censored event history data. We propose pseudo-observation-based estimators for the area under the time varying receiver operating characteristic curve, for optimizing the ensemble, and the predictiveness curve, for evaluating and summarizing predictive performance.
EFFECT OF CROSS‐BORDER HEALTH CARE ON QUALITY AND PROGRESSIVITY OF FINANCING
Authors: Aiura Hiroshi
Published: July 2019

In this study, we examine the effect of cross‐border health care in terms of public health insurance. We consider its effect on healthcare quality and progressivity of financing. We use a two‐country Hotelling model in which consumers are divided into two groups: high and low innate‐talent consumers. Aiming to maximize social welfare, governments impose a progressive income tax on consumers to provide healthcare services. Assuming that a payment scheme for healthcare services is based on diagnosis‐related group pricing, which has been adapted in many countries, we obtain the following results. The promotion of cross‐border health care does not influence healthcare quality or the progressivity of financing in patient‐importing countries, but does reduce healthcare quality and influence the progressivity of financing in patient‐exporting countries.
Public Health Surveillance of Youth Suicide Attempts: Challenges and Opportunities
Authors: Singleton Michael D. , Frey Laura M. , Webb Ashley , Cerel Julie
Published: July 2019

Background

Surveillance of youth suicide attempts presents many challenges. To assess common data sources that capture information about youth suicidal behavior, we compared counts of high school students who reported (a) a suicide attempt and (b) an injurious suicide attempt, requiring medical treatment in the previous twelve months, with counts of suicide deaths and intentional self‐injuries obtained from administrative data sources.

Method

Youth Risk Behavior Surveillance System (YRBSS), high school enrollments, and vital statistics were used to estimate the ratio of suicide attempts to suicide deaths among Kentucky high school students. YRBSS and enrollment data were used to estimate the number of Kentucky high school students who received medical treatment following a suicide attempt, which was compared with hospital and emergency department (ED) discharges for intentional self‐injury from administrative claim records.

Results

We estimated 943 students reporting a suicide attempt for every suicide death, a result that is higher than previous estimates for youth. Self‐reported suicide attempts resulting in medical treatment were 7.5 times higher than self‐injuries reported in claims records.

Conclusion

Future research should address concerns about undocumented cases of intentional self‐injury in administrative claims systems; patient encounters in nonhospital settings for injuries resulting from a suicide attempt; and validity of Youth Risk Behavior Survey questions on suicidal behavior.
Stochastic comparisons of multivariate reversed frailty model
Authors: Bansal Shilpa , Gupta Nitin
Published: July 2019

Multivariate frailty approaches are most commonly used to define distributions of random vectors, which represent lifetimes of individuals or components and stochastically compare them in terms of various multivariate orders. In this paper, we study a multivariate shared reversed frailty model and a general multivariate reversed frailty mixture model, and derive sufficient conditions for some of the stochastic orderings to hold among the random vectors. We also consider a particular case of a general multivariate mixture model in which the baseline distribution function is represented in terms of a copula and study stochastic comparisons (stochastic and lower orthant order) among the two random vectors.
Radiographic characteristics of alveolar microlithiasis and pulmonary ossification following chronic corticosteroid therapy in a dog
Authors: Jorge Kelsey M. , Huguet Elodie E. , Finley Abigail , Dulaney D. Ryan , Cocchiaro Michael , Montiel‐Del Valle Anabell , Berry Clifford R.
Published: July 2019

A 10‐year‐old, neutered female, Australian Shepherd was referred for acute respiratory distress and a history of chronic exogenous steroid administration. On thoracic radiographs, a severe increase in mineral opacity characterized as a generalized unstructured interstitial pulmonary pattern, diffuse calcinosis cutis, and moderate hepatomegaly were noted. Cor pulmonale was identified on echocardiography. The patient developed a pneumothorax following sampling and had a cardiac arrest. Postmortem histopathology of the lungs revealed pulmonary interstitial mineralization and alveolar microlithiasis. This report supports including generalized pulmonary mineralization due to chronic exogenous steroid administration as a differential diagnosis for dogs with these clinical and imaging findings.
Impact of Functional Nanofluid Coolant on Radiator Performance
Authors: Salem Thamer Khalif , Nazzal Ibrahim Thamer , Arik Mehmet , Budakli Mete
Published: July 2019

While a number of liquids are preferred in many heating and cooling applications, their thermal capacity can be a limiting factor in many thermal systems. Therefore, a series of methods such as use of mixtures of two or more fluids, emulsions, phase change materials, and more recently nanoparticle enriched fluids have been proposed. The impact of adding aluminum and copper nanoparticles to water in a closed-loop radiator has been investigated analytically and numerically. Heat transfer performances of different working fluids are studied under the same boundary conditions. The analytical and numerical models including external and internal flow domains of the radiator have been developed, and free convection air cooling has been considered over external surfaces of a radiator. Both plain and nanoparticle added fluid cases are analyzed individually to differentiate the impact over heat transfer. The results indicate that the presence of nanoparticles effectively raised the convective heat transfer coefficient and thus the performance of the radiator system increased by 2.1% and 0.6%, respectively, in comparison to plain water operating condition. Furthermore, the radiator tube length has been shortened by 2.0% and 0.75% for both Al and Cu nanoparticle filled fluid, respectively, to obtain the same thermal performance at a single tube. The total required heat transfer surface area is also reduced by 2.0% and 1.15% for Al and Cu, respectively. Finally, a comparison between analytical and numerical models has been found to be in a good agreement of heat transfer coefficient and Nusselt number.
Experimental Modeling of Railway Car Wheel-Forces During Turning
Authors: Otremba Frank , Romero Navarrete José Antonio
Published: July 2019

The interaction of the carried cargo and the carrying vehicle involves many aspects that can affect the transport safety from different perspectives. On the one side, the lateral inertial forces developed by sloshing cargo can affect the lateral stability of the vehicle, while at long term, such dynamic forces can affect the integrity of the infrastructure’s components, which can lead to transport accidents. In this paper, a tilt-table based testing rig is presented to simulate the dynamic response of the vehicle-cargo system to lateral accelerations associated to turning maneuvers. The conceptual design and final construction/instrumentation of the equipment are described. As a first use of the testing rig, a five-parameter two-degree of freedom simplified mechanical model for the liquid cargo – vehicle interaction is calibrated, yielding a high correlation with the experimental data (0.98). The improvement of the theoretical model is further discussed, as the model underestimates the loading cycles to the infrastructure, in 20%.
Study on Running Safety of Railway Tank Car Based on the Experimental Identification Model
Authors: Jimin Zhang , Qiao Ren
Published: July 2019

In the present work, we will discuss the vibration spectrum impact of water and sand inside a railway container. To do so, a scaled model of a container car was driven on tracks with three accelerometers on its side to record the container response. The experiment was conducted with three different water fill levels and two sand masses. As the data given by the accelerometers was recorded in an ambient vibration environment, the random decremental technique was used to determine the system’s free vibration response. Then the wavelet transform was applied in order to obtain the modal parameters of the structure. The results were then compared to draw conclusions on the effect of water and sand on the tank.
Defect Growth Characterization in Modern Rail Steels
Authors: Jeong David Y. , Woelke Pawel B. , Nied Herman F. , DuPont John N. , Kizildemir Sena , Fletcher Fred B. , Hutchinson John W.
Published: July 2019

The Federal Railroad Administration (FRA) has been sponsoring research on rail integrity for several decades. This research has been chiefly managed and conducted by the Volpe National Transportation Systems Center (Volpe). Particular focus has been given in this research to rail head defects, known as detail fractures, since they are the most commonly encountered defect in continuous welded rail track [1]. Testing and analyses have been performed on railroad rails manufactured without head hardening.

Modern rail, however, are now heat treated during the manufacturing process to harden the rail surface to increase its resistance to wear. As such, the heat treatment and nonuniform cooling induce complex residual stress patterns in the rail that can affect microstructure and fatigue crack growth rate behavior.

This paper will describe research to examine defect growth behavior of modern rail steels. This research is a collaboration among several organizations: Thornton-Tomasetti, Arcelor-Mittal, Lehigh University, Harvard University, National Institute of Standards and Technology (NIST), Fraunhofer Institute, and Volpe. Arcelor Mittal donated rails with different grades of steel: advanced head hardened, head hardened, and standard strength (i.e. non-head-hardened). Lehigh conducted laboratory tests on specimens cut from these rails to perform various tests, which include: hardness measurements, mechanical testing to measure tensile properties, fracture toughness measurements, and fatigue crack growth rate tests. All of these tests were performed in accordance with applicable ASTM International standards. NIST and Fraunhofer performed preliminary neutron diffraction measurements of residual stresses on the different rails.

Moreover, this paper will present results from the laboratory testing program. Implications of these results on detail fracture growth behavior will also be discussed.
Estimation of Rail Vertical Profile Using an H-Infinity Based Optimization With Learning
Authors: Liang Xiao , Zheng Minghui
Published: July 2019

Railway track vertical alignment is an important indicator of serviceability condition and thus plays a critical role for maintenance planning. Estimating the rail profile through the vertical acceleration readings provides an efficient alternative to the current practice of optical methods using special vehicles. This paper proposes an algorithm to estimate the rail vertical profile using the vertical acceleration of the vehicle resulting from the train-track dynamic interaction. The algorithm is designed to approximate the inverse of the transfer function from the rail vertical roughness to the train’s measured acceleration. The approximation problem is formulated into an H-infinity optimal control design problem, which can be further transferred into a problem of convex optimization. The proposed algorithm possesses several advantages including easy design, little tuning effort, and low computational cost. In addition, to take into account the model uncertainty, an optimization-based learning framework is proposed to further enhance the performance of the proposed algorithm. The numerical study has been conducted comprehensively to validate the observer’s properties and effectiveness in reconstructing of the rail vertical roughness.
Evaluation of the Remaining Prestress Force and Center Negative Bending Moment in Crossties Removed From Track After 25 Years of Service
Authors: Scott James D. , Peterman Robert J. , Robertson Aaron A. , Beck B. Terry , Riding Kyle A.
Published: July 2019

Extensive research is currently being conducted by the team to understand the prestressing steel and concrete properties that cause high bonding stresses and lead to longitudinal splitting cracks, and how to mitigate this failure in future designs. One parameter of interest that affects the bonding stress is the amount of prestressing force in a crosstie. To help quantify the amount of prestress force necessary to provide a durable long-term crosstie, a study on existing crossties that have performed well in track for over 25 years was conducted to evaluate the center negative bending moment, and determine the remaining prestress force for each tie.

The remaining prestress force in each tie was determined using a new proposed method in which ties are loaded in direct tension. The new test method was also conducted on new ties instrumented with vibrating wire strain gages to verify the method. The testing results reveal that a majority of the existing ties evaluated have a remaining prestress force in the range of 84–95 kips. These forces are significantly lower than the remaining prestress force after losses of newer tie designs. This can be seen when comparing the tension test results of the existing ties with the results of the new ties.

Ties were loaded upside-down in four-point bending to determine their center negative cracking moments. The test setup and procedure used closely resembles the center negative bending moment test outlined in AREMA 30, with minor variations. For each different tie design in the study, the center negative design moment was calculated following the AREMA 30 procedure, and compared to the experimental cracking moments. Of the seven different existing tie designs investigated, four would meet the requirements of the current AREMA 30 center negative bending test.
Train-Induced Load Effects on the Thermal Track Buckling
Authors: Pucillo Giovanni Pio
Published: July 2019

Thermal track buckling is probably the major problem due to the advent of continuous welded rail track. In fact, when the rails temperature rises over a critical value, the track can buckle, suddenly or progressively, in the lateral plane. Both poor ballast conditions and large lateral alignment defects are the principal causes of such phenomenon.

In a previous paper, a parametric finite element model for thermal track buckling simulation was presented and validated by comparison with analytical results of the literature. In this study, the finite element model has been further validated by comparison with analytical and numerical results obtained by three other authors.

Moreover, to take into account the effect on the buckling temperatures of the vertical loads due to train passes, the tie-ballast lateral resistance has been modified along the track, taking into account the vertical reaction forces distribution induced by axle loads.

A sensitivity analysis has been carried out both for tangent and curved track, considering two values of the alignment defect amplitude, and different values of the parameters that characterize actual railway vehicles.

It is found that the conditions to trigger progressive buckling (△Tmax ≈ △Tmin) are attained with small values of the truck center distance, and in a more accentuated manner in the presence of high values of the lateral alignment defect.

△Tmax and △Tmin increase with axle spacing, and this increase is more pronounced for low values of the truck center spacing. △Tmax and △Tmin also increase with curve radius, but decrease for increasing values of the misalignment defect amplitude.

In explosive buckling conditions (△Tmax ≠ △Tmin), there is a limit value of the truck center distance above which the vertical load has no more effects, and the results of the static thermal buckling are found.
Evaluation of Splitting Crack Propagation in Pre-Stressed Concrete Ties Made With Different Types of Coarse Aggregate
Authors: Shafiei Dastgerdi Aref , Savic Adrijana , Peterman Robert J. , Riding Kyle , Beck B. Terry
Published: July 2019

Pre-stressed concrete railroad ties must meet requirements during service life. Using pre-stressed wires in concrete members enhances load-carrying capacity of concrete ties. It is important to ensure that pre-stressed forcing is introduced well before rail seat where the high impact load is applied. The required length of wire to fully transfer pretension forcing to concrete member is referred as transfer length. In order to shorten the transfer length, wires with improved indentation are used. As the transfer length is shortened, the high amount of stress concentration at the interface of wire-concrete can lead to longitudinal splitting cracks in concrete railroad ties. Splitting crack can occur either right after de-tensioning or during service life. It has been observed that concrete properties and components can highly affect crack formation and propagation. In this research, the effect of coarse aggregate on the splitting cracks of concrete railroad ties was investigated. To assess the impact of coarse aggregate features on splitting crack performance, fracture toughness test was done on three-point bend prisms. The specimens were made of four different coarse aggregate including crushed aggregate and well-rounded aggregate. It was observed that angularity and coarseness of aggregate increases the fracture toughness of concrete by 20%. Then, the same mixes were used in fabrication of pre-stressed prisms with different cover length to evaluate actual performance of splitting cracks after de-tensioning. The wires were tensioned up to 7000 Ib per wire and de-tensioned when concrete strength of 4500 psi is reached. The results of crack area/length of splitting cracks showed that increasing angularity can significantly improve splitting cracks resistance.
Prototyping a Conductive Polymer Steering Pad for Rail Freight Service
Authors: Villarreal Anthony A. , Tarawneh Constantine , Ontiveros Miguel , Aranda James , Jones Robert
Published: July 2019

The AdapterPlus™ steering pad is a polymer component on a railcar that helps to reduce stresses on the axle as a railcar rounds a curve. One railway application requires a minimum of 240 mA to be passed through the steering pad to the rail, which activates air valves that control automated cargo gates. Currently, two copper studs are inserted into the pad to provide a conductive path. However, after continuous cyclic loading caused by normal service operation, the copper studs deform, wear, and eventually lose contact between the two surfaces rendering the pad nonconductive. One proposed solution to this problem is to create a steering pad made entirely from an electrically conductive material. The University Transportation Center for Railway Safety (UTCRS) research team has successfully created a conductive nanocomposite made from vapor grown carbon nanofibers (CNFs) and a modified form of Elastollan 1195A thermoplastic polyurethane (TPU). Previous attempts to create this material were promising but failed to produce an electrically conductive specimen when injection molded. Preliminary results have shown that the new material can be injection molded to create an electrically conductive test specimen.

An injection molded insert was designed, fabricated, and incorporated into the existing steering pad design for further testing. Pressure measurement film had previously been used to find the points of maximum stress inside the pad to optimize the design of the composite insert. Characterization of the resistivity of the composite material was carried out in order to verify functionality in future iterations of this product. The resistance of the composite material is expected to be non-linear with a strong dependence on load and voltage. Conductivity tests were performed using a material testing system with a compressive load ranging from 1500 pounds to 5500 pounds. The voltage at each load was also varied between 10V to 20V and the nonlinear resistance of the material was examined. The results have shown that the CNF/TPU composite is a potential replacement for the current TPU used for the pad and, with minimal modifications, can be implemented in field service operation.
Milwaukee Streetcar Overhead Contact System: A Challenging Design Effort
Authors: White Paul F. , Kola Gerti
Published: July 2019

The new Milwaukee Streetcar system has been in the planning, design and construction phases for over 10 years and on November 2, 2018, operations with a combined overhead contact system and streetcar battery power commenced ushering in a new era of growth for the City of Milwaukee. Many challenges in the design and construction of the overhead contact line and power system were encountered during this time period including budgetary constraints, multiple pole location changes, underground obstacles, low clearance bridges, alignment changes, utility conflicts, and changing vehicle requirements.

The line was originally designed for pantograph operation but soon adapted for pole/pantograph current collection and then changed back to pantograph only current collection during the final design. The original design consisted of underground feeder cables to supplement a 4/0 contact wire but eventually not utilized due to budgetary constraints. Instead, a larger 350 kcmil contact wire was used with no paralleling feeder cables. The added weight of a 350 kcmil wire with wind, ice and low temperatures created high forces in the overhead contact system (OCS) leading to challenges in pole and foundation design where compliance to the National Electrical Safety Code (NESC) was required.

The OCS style originally proposed and finally constructed used an inclined pendulum suspension (IPS) system that was constant tensioned with rotating springs deemed by the installing contractor superior to balance weights. The pendulum system was chosen as it is simple, lightweight, less visually obtrusive, and more economical than other suspension systems such as stitch and steady arm that are being used on other streetcar or light rail systems. IPS has provided Milwaukee with an excellent operating overhead contact system.

Buildings along the route that were not historic structures were utilized where possible for span wire attachment but in many locations long bracket arms up to 40 feet long had to be used requiring special designs to keep the size of the pipes standard with the rest of the system. Challenges arose at low bridge underpasses where the contact wire had to be below required code height and special precautions had to be undertaken. Other areas such as the St. Paul Lift Bridge proved challenging as well where special electrically interlocked OCS devices were initially designed to de-energize the overhead wires and is further discussed with the reasoning for their use.

This paper outlines the phases of design, the changes to the design that occurred over time, the challenges encountered to the OCS design, the method of design, and the final disposition of the design for construction. It further outlines the construction of the system and problems encountered with poles, foundations, bracket arms, traction power substations, contact wire, feeder cables, and winter conditions affecting the integrity of these structures and how some of these problems were solved.
Optimizing Railway Track Maintenance Scheduling to Minimize Circulation Impacts
Authors: Bueno Paulo M. S. , Vilela Plínio R. S. , Christofoletti Luciano M. , Vieira Anderson P.
Published: July 2019

1 In this paper we present an optimization based technique to allocate time windows for railroad track maintenance in order to minimize the impact on train circulation. The hypothesis is that it is possible to reduce the impact on train circulation if track maintenance slots are scheduled in naturally occurring gaps on the circulation, instead of just using a decision making process that does not take the train circulation into consideration.

The proposed solution uses simulated annealing as the basis for the algorithm and yields promising results when a random initial placement of track blocks is used. We show the results of our experiments that consider as restrictions the earliest initial time for the track block and the latest termination time for the track blocks (to account for restriction in crew work hours, for example). For this work we do not restrict the number of simultaneous maintenance teams that could be working, future investigations will account for that restriction.
Stochastic Analysis of Transit Wheel Wear and Optimized Forecasting of Wheel Maintenance Requirements
Authors: Palese Joseph W. , Zarembski Allan M. , Ebersole Kyle
Published: July 2019

As transit vehicle wheels accrue mileage, they experience flange and tread wear based on the contact between the railhead and wheel-running surface. When wheels wear excessively, the likelihood of accidents and derailments increases. Thus, regular maintenance is performed on the wheels, until they require replacement. One common maintenance practice is truing; using a specially designed cutting machine to bring a wheel back to an acceptable profile. This process removes metal from the wheel and is often based on wheel flange thickness standards (and sometimes wheel flange angle). Wheel replacement is usually driven by rim thickness, which is continually reduced by wear and metal removed by truing.

This research study used wheel wear data provided by the New York City Transit Authority (NYCTA) to analyze wheel wear trends and forecast wheel maintenance (truing based on flange thickness) and wheel life (replacement based on rim thickness). Using automatic wheel-scanning technology, NYCTA was able to collect wheel profile measurements for nearly 4,000 wheels in its fleet over a six-month period, measured weekly. The resulting wheel measurement data was analyzed using advanced stochastic techniques to determine relationships for the changes in flange thickness over time for each wheel in the fleet.

Flange thickness wear rate relationships for each wheel were then used to forecast the time it would take for a wheel to reach the flange thickness maintenance threshold as defined by NYCTA standards. Furthermore, a subpopulation of wheels that exhibited very high rates of wear were classified as “bad actors” and identified for further investigation to understand the cause of accelerated wear. This allows for identification and addressing of causal factors that relate to accelerated wear, such as angle of attack and L/V ratio. NYCTA has recently started capturing such data that relates truck performance, which can be related to rate of wear.
How Staged Head-On Collisions Changed Public Perception of Railroads
Authors: Thurston Leanne
Published: July 2019

With any new mode of transportation comes new fears for both the public and those involved in the industry. The advent of the transcontinental railroad was no different. When the transcontinental railroad was complete and trains became more commonplace for travel, the biggest fear became the worst case scenario: a head on collision between two trains. The idea of the head on collision remained the biggest fear of the public because it happened and was based on reality, but was rarely witnessed, which made the idea even more lofty. But with the standardization of time in the 1880’s, there were fewer crashes and collisions of railroads, but people were still afraid. Railroad companies began to brainstorm the best way to change public perception, and began to stage head on collisions open to public viewing for a small fee.

Naturally, the idea took off, and head on collisions between trains became the next source of entertainment. For $2, spectators could watch two locomotives crash into each other at speeds of 58 miles an hour in Crush Texas, or even cheaper in Ohio. But this was more than just entertainment. William Crush, the most famous locomotive smasher had actually worked on the railroad known as the Katy. When asked by the executives of the railroad to boost sales, head on collision was his solution. Despite multiple injuries suffered in the crowd from shrapnel and an exploded boiler, this showcase worked, and ridership of the Katy increased dramatically. Crush’s display was not the first, or last time this took place around the country, but it was the most deadly, which makes it the most memorable and begs the question “what role do these staged collisions play in railroad history?”

Ridership in the decades leading up to these staged collisions was steadily declining, and safety measures were not taken into consideration. But with these staged collisions that turned around. People, not just the public were able to see and study the different collisions and put minds at ease. But it also tells about the United States population at the time. These staged collisions could not have happened in any other era because of the industrial revolution which allowed railroad companies to begin to replace old locomotives and iron tracks with steel.
Bovine serum albumin, aqueous solution, by near-ambient pressure XPS
Authors: Jain Varun , Kjærvik Marit , Bahr Stephan , Dietrich Paul , Meyer Michael , Thißen Andreas , Linford Matthew R.
Published: July 2019

Near-ambient pressure x-ray photoelectron spectroscopy (NAP-XPS) is a less traditional form of XPS that allows samples to be analyzed at relatively high pressures, i.e., at greater than 2500 Pa. With NAP-XPS, XPS can probe moderately volatile liquids, biological samples, porous materials, and/or polymeric materials that outgas significantly. In this submission, we show survey, C 1s, O 1s, and N 1s narrow scans from an aqueous solution of a common protein, bovine serum albumin. The C 1s peak envelope is well fit to four symmetric peaks of equal width that correspond to carbon bonded to carbon and hydrogen (C-1), carbon singly bonded to oxygen (C-2), carbonyl and/or amide carbon (C-3), and carboxyl carbon (C-4). Two possible peak fits are considered for the N 1s and O 1s peak envelopes. The N 1s signal is fit to four peaks that correspond to amine (—NH2), amide (O˭C‒NH2), ammonium (—NH3+), and N2(g) nitrogen, and alternatively to three peaks that correspond to amine, amide, and N2(g) nitrogen. The O 1s peak envelope is similarly fit to three and four components.
The hardwall method of solving the radial Schrödinger equation and unmasking hidden symmetries
Authors: Chin Siu A. , Massey John
Published: July 2019

Solving for the bound state eigenvalues of the Schrödinger equation is a tedious iterative process using the conventional shooting or matching method. In this paper, we bypass a eigenvalue's dependence on the eigenfunction by trying all eigenvalues to a desired accuracy. When the eigenvalue is known, the integration for the eigenfunction is then trivial. By outputting the radial distance at which the wave function crosses zero (the hardwall radius) for a given energy, the hardwall method automatically determines the entire spectrum of eigenvalues of the radial Schrödinger equation without iterative adjustments. Moreover, such a spherically symmetric hardwall can unmask the accidental degeneracy of eigenvalues due to hidden symmetries. We illustrate the method for the Coulomb, harmonic, Coulomb plus harmonic, and the Woods-Saxon potentials.
Alternative statements of the Rayleigh monotonicity law for linear time-invariant resistor networks driven by only voltages or only currents
Authors: Karrila Seppo J. , Karrila Alex
Published: July 2019

Networks of linear time-invariant (LTI) resistors are a classical topic with many applications, used to model a variety of flow phenomena. In this short communication, we provide conceptually simple proofs of the following intuitively appealing bounds, which also imply the classical Rayleigh monotonicity law (RML): (i) For an LTI resistor network, driven by some node voltages, when a set of resistors is removed the total power dissipation is reduced by at least an amount that was consumed in the removed resistors. (ii) The complementary or dual result for such a network, but when current driven, is that shorting some resistors decreases the total power dissipation by at least as much as used to occur in these resistors before shorting. In fact, ideal diodes can be allowed as network branches and the same results hold. The short derivations assume that Dirichlet's and Thomson's minimum principles are known. With the expanding applications of a linear network theory, we hope that these variants of the monotonicity theorem will prove pedagogically useful.