bluuebunny/crossref_metadata_2025 huggingface dataset:
Allogeneic mesenchymal stem cells prevent allergic airway inflammation by inducing murine regulatory T cells
Authors: Kavanagh H. , Mahon B. P.
Published: November 2010

To cite this article: Kavanagh H, Mahon BP. Allogeneic mesenchymal stem cells prevent allergic airway inflammation by inducing murine regulatory T cells. Allergy 2011; 66: 523–531.

Background:  Adult bone marrow‐derived mesenchymal stem cells (MSC) possess potent immune modulatory effects which support their possible use as a therapy for immune‐mediated disease. MSC induce regulatory T cells (Treg) in vitro although the in vivo relevance of this is not clear.

Objective:  This study addressed the hypothesis that adult bone marrow derived‐MSC would prevent the pathology associated with allergen‐driven airway inflammation, and sought to define the effector mechanism.

Methods:  The influence of allogeneic MSC was examined in a model system where Treg induction is essential to prevent pathology. This was tested using a combination of a model of ovalbumin‐driven inflammation with allogeneic MSC cell therapy.

Results:  Systemic administration of allogeneic MSC protected the airways from allergen‐induced pathology, reducing airway inflammation and allergen‐specific IgE. MSC were not globally suppressive but induced CD4+FoxP3+ T cells and modulated cell‐mediated responses at a local and systemic level, decreasing IL‐4 but increasing IL‐10 in bronchial fluid and from allergen re‐stimulated splenocytes. Moderate dose cyclophosphamide protocols were used to differentially ablate Treg responses; under these conditions the major beneficial effect of MSC therapy was lost, suggesting induction of Treg as the key mechanism of action by MSC in this model. In spite of the elimination of Treg, a significant reduction in airway eosinophilia persisted in those treated with MSC.

Conclusion:  These data demonstrate that MSC induce Tregin vivo and reduce allergen‐driven pathology. Multiple Treg dependent and independent mechanisms of therapeutic action are employed by MSC.
Structural and functional analyses of a saturated acyl ACP thioesterase, type B from immature seed tissue of Jatropha curcas
Authors: Srikanta Dani K. G. , Hatti K. S. , Ravikumar P. , Kush A.
Published: November 2010

The distinguishing structural and functional domains of plant acyl‐acyl carrier protein (ACP) thioesterases and their complex interaction with the ACP‐linked fatty acid substrate complex have remained elusive. E. coli based heterologous expression and characterisation of many plant thioesterases reported so far have not been extended and linked to in silico modelling studies to explain the diversity in plant thioesterase substrate specificities. In this study, a thioesterase cDNA isolated from immature seed tissues of Jatropha curcas was found to be type B and specific to stearoyl acyl ACP when expressed in E. coli K27fadD88, a lipid utilisation mutant. Homology modelling and molecular docking of a selected region of the isolated JcFatB protein predicted that it had high affinity towards both stearate (18:0) and palmitate (16:0). Structural analysis of the sequence confirmed the presence of a transit peptide that is processed in multiple steps. The enzyme is localised in the chloroplasts and has an N‐terminal inner chloroplast transmembrane domain characteristic of type B plant thioesterases. Docking of ligands with JcFatB and its comparison with a modelled Jatropha thioesterase type A provided further evidence for native substrate preferences of Jatropha thioesterases. This study provides essential clues to develop future methods for large‐scale bacterial production of free fatty acids and for design of strategies to modulate the seed oil composition in this important non‐edible, seed oil plant.
Obesity, metabolic syndrome, adipocytes and vascular function: A holistic viewpoint
Authors: Achike Francis I , To Nim‐Hin Peter , Wang Huidi , Kwan Chiu‐Yin
Published: November 2010

1. Obesity is a metabolic disease of pandemic proportions largely arising from positive energy balance, a consequence of sedentary lifestyle, conditioned by environmental and genetic factors. Several central and peripheral neurohumoral factors (the major ones being the anorectic adipokines leptin and adiponecin and the orexigenic gut hormone ghrelin) acting on the anorectic (pro‐opiomelanocortin and cocaine‐ and amphetamine‐regulated transcript) and orexigenic (neuropeptide Y and agouti gene‐related protein) neurons regulate energy balance. These neurons, mainly in the arcuate nucleus of the hypothalamus, project to parts of the brain modulating functions such as wakefulness, autonomic function and learning. A tilt in the anorectic–orexigenic balance, perhaps determined genetically, leads to obesity.

2. Excess fat deposition requires space, created by adipocyte (hypertrophy and hyperplasia) and extracellular matrix (ECM) remodelling. This process is regulated by several factors, including several adipocyte‐derived Matrix metalloproteinases and the adipokine cathepsin, which degrades fibronectin, a key ECM protein. Excess fat, also deposited in visceral organs, generates chronic low‐grade inflammation that eventually triggers insulin resistance and the associated comorbidities of metabolic syndrome (hypertension, atherosclerosis, dyslipidaemia and diabetes mellitus).

3. The perivascular adipose tissue (PVAT) has conventionally been considered non‐physiological structural tissue, but has recently been shown to serve a paracrine function, including the release of adipose‐derived relaxant and contractile factors, akin to the role of the vascular endothelium. Thus, PVAT regulates vascular function in vivo and in vitro, contributing to the cardiovascular pathophysiology of the metabolic syndrome. Defining the mechanism of PVAT regulation of vascular reactivity requires more and better controlled investigations than currently seen in the literature.
Clinical significance of the highly sensitive fucosylated fraction of α‐fetoprotein in patients with chronic liver disease
Authors: Hanaoka Takuya , Sato Shuichi , Tobita Hiroshi , Miyake Tatsuya , Ishihara Shunji , Akagi Shuji , Amano Yuji , Kinoshita Yoshikazu
Published: November 2010

Background and Aim:  The purpose of the present study was to investigate the clinical significance of the highly sensitive fucosylated fraction of α‐fetoprotein (hs‐AFP‐L3) in patients with chronic liver disease (CLD) and low serum α‐fetoprotein (AFP) concentration.

Methods:  A total of 241 patients being treated at our institute with CLD and low serum AFP concentration (3–10 ng/mL) were investigated retrospectively. We measured total AFP and the percentage of AFP‐L3 using a µTAS Wako i30 device. The possible presence of hepatocellular carcinoma (HCC) was thoroughly investigated by various examinations carried out from 1 month before to 1 month after measurements. In addition, hs‐AFP‐L3 elevated and non‐elevated groups, divided by the cut‐off value based on a receiver–operator characteristic (ROC) curve, were followed for possible future development of HCC.

Results:  hs‐AFP‐L3 was above the detectable range in 60 patients (24.9%). Among those AFP‐L3 positive cases, 20 (33.3%) were found to be HCC prevalent, whereas HCC was found in just 16 patients (8.8%) with undetectable hs‐AFP‐L3 levels. We determined the cut‐off value of hs‐AFP‐L3%, which shows the proportion of AFP L3 in total AFP, to be 5.75%. During the follow‐up period, HCC was newly detected in six patients (22.2%) in the hs‐AFP‐L3% elevated group and in 10 (5.6%) in the non‐elevated group. Analysis using the Kaplan–Meier method showed the HCC‐free rate of the hs‐AFP‐L3% elevated group was significantly lower than that of the non‐elevated group (P = 0.0038). Independent predicting variants were female sex (P = 0.0024) and hs‐AFP‐L3% elevation (P = 0.0036).

Conclusion:  Our results suggest hs‐AFP‐L3 level is a useful tumor marker for HCC in patients with CLD and low serum AFP concentration.
Epidemiology of lower gastrointestinal bleeding in China: Single‐center series and systematic analysis of Chinese literature with 53 951 patients
Authors: Bai Yu , Peng Jun , Gao Jun , Zou Duo‐Wu , Li Zhao‐Shen
Published: November 2010

Objectives:  The epidemiology of lower gastrointestinal bleeding (LGIB) in Western populations has been reported; however, there are scant Asian reports. The aim of the present study was to determine the etiology of LGIB in a Chinese population by reporting a retrospective case series and a systematic analysis of Chinese literature.

Methods:  A large colonoscopy database in a tertiary endoscopic center was searched to identify all patients with the indication of LGIB. The data, including patients' sex, age, endoscopic and pathological findings, were collected and analyzed. A comprehensive database search of the Chinese literature was carried out to obtain all relevant studies.

Results:  In our series, a total of 720 patients with LGIB were included. There were 425 males and 295 females with a median age of 50 years, the most common etiologies of LGIB were inflammatory bowel disease (IBD; 30.2%), polyps (23.4%) and cancer (10.7%). In 30.2% of all the patients, no obvious causes were identified. A systematic analysis of Chinese literature found an additional 160 studies providing relevant data in 53 951 patients. Overall, colorectal cancer (24.4%), colorectal polyps (24.1%), colitis (16.8%), anorectal disease (9.8%) and IBD (9.5%) were the most common etiologies of LGIB. The main etiologies were different between adults, the elderly and children.

Conclusion:  The study shows colorectal cancer, colorectal polyps, colitis, anorectal disease and IBD were the most common etiologies of LGIB in the Chinese adult and elderly population, whereas colorectal polyps, chronic colitis and intussusception were the main causes of LGIB in Chinese children. Whereas diverticulum, the most common cause of LGIB in Western populations, is uncommon in China.
Twist1 and Y‐box‐binding protein‐1 promote malignant potential in bladder cancer cells
Authors: Shiota Masaki , Yokomizo Akira , Itsumi Momoe , Uchiumi Takeshi , Tada Yasuhiro , Song YooHyun , Kashiwagi Eiji , Masubuchi Daisuke , Naito Seiji
Published: November 2010

What’s known on the subject? and What does the study add?

So far, transcription factor Twist1 has been reported to regulate Y‐box binding protein‐1 (YB‐1) expression and play important roles in tumour growth, invasion and drug resistance. This study revealed that in bladder cancer cells, Twist1 regulated YB‐1 transcription and both Twist1 and YB‐1 promote malignant potentials including tumour growth, invasion and anticancer‐drug resistance.

Although the relation between Twist1/YB‐1 signaling and cancer malignant potentials including tumour growth, invasion and anticancer‐drug resistance have been suggested, their roles in bladder cancer remain unknown. This study revealed their functional importance in bladder cancer, indicating that both Twist1 and YB‐1 are promising molecular targets in bladder cancer.

OBJECTIVE

• To investigate the roles of Twist1 and Y‐box binding protein‐1 (YB‐1) and their potential as therapeutic targets in bladder cancer (BC), as both have been suggested to play important roles in tumour growth, invasion and drug resistance.

MATERIALS AND METHODS

• Bladder cancer cell lines (TCCsup, UMUC3, T24 and KK47 cells) were used.

• Twist1 and YB‐1 expression levels were assessed by luciferase reporter assay, quantitative real‐time polymerase chain reaction (PCR) and western blot analysis.

• Tumour growth and cell cycle were analysed by cell proliferation assay and flow cytometry, respectively.

• Invasive and motile abilities were investigated by scratch‐wound test and migration assay, respectively. Cytotoxicity assay was performed to determine drug sensitivity.

RESULTS

• The findings showed that Twist1 regulated YB‐1 expression in BC cells.

• Both Twist1 and YB‐1 were involved in cell growth, invasion, motility and resistance to cisplatin and doxorubicin, but not to 5‐fluorouracil (5‐FU).

CONCLUSION

• The present study showed that Twist1 regulates YB‐1 expression and that both Twist1 and YB‐1 promote malignant potentials, including tumour growth, invasion and anti‐cancer‐drug resistance, indicating that both Twist1 and YB‐1 are novel molecular targets in BC.
Early prostate cancer – which treatment do men prefer and why?
Authors: Anandadas Carmel N. , Clarke Noel W. , Davidson Susan E. , O’Reilly Patrick H. , Logue John P. , Gilmore Lynne , Swindell Ric , Brough Richard J. , Wemyss‐Holden Guy D. , Lau Maurice W. , Javle Pradip M. , Ramani Vijay A.C. , Wylie James P. , Collins Gerald N. , Brown Stephen , Cowan Richard A. ,   On behalf of the North West Uro‐oncology Group
Published: November 2010

Study Type – Preference (prospective cohort) Level of Evidence 1b

What’s known on the subject? and What does the study add?

In general the literature suggests that there is a need for improvement in aiding men diagnosed with early prostate cancer in their decision making about treatment options and that our understanding of this process is inadequate. There is limited data analyzing the reasons why these men decide between potentially curative or observational treatments and data evaluating patients’ views before and after definitive therapy are scarce.

This study begins the process of understanding the reasons underlying a patient’s final treatment decision. Being a prospective study, it looks at the thought processes of these men before treatment during the time the decision is made. It also documents how satisfied patients are with their choice after their treatment and whether they would choose the same treatment again.

OBJECTIVE

• To identify the reasons for patients with localised prostate cancer choosing between treatments and the relationship of procedure type to patient satisfaction post‐treatment.

PATIENTS AND METHODS

• 768 men with prostate cancer (stage T1/2, Gleason ≤7, PSA <20 ug/L) chose between four treatments: radical prostatectomy, brachytherapy, conformal radiotherapy and active surveillance.

• Prior to choosing, patients were counselled by a urological surgeon, clinical (radiation) oncologist and uro‐oncology specialist nurse.

• Pre‐treatment reasons for choice were recorded. Post‐treatment satisfaction was examined via postal questionnaire.

RESULTS

• Of the 768 patients, 305 (40%) chose surgery, 237 (31%) conformal beam radiotherapy, 165 (21%) brachytherapy and 61 (8%) active surveillance.

• Sixty percent of men who opted for radical prostatectomy were motivated by the need for physical removal of the cancer.

• Conformal radiotherapy was mainly chosen by patients who feared other treatments (n = 63, 27%). Most men chose brachytherapy because it was more convenient for their lifestyle (n = 64, 39%).

• Active surveillance was chosen by patients for more varied reasons. Post‐treatment satisfaction was assessed in a subgroup who took part in the QOL aspect of this study.

• Of the respondents to the questionnaire, 212(87.6%) stated that they were satisfied/extremely satisfied with their choice and 171(92.9%) indicated they would choose the same treatment again.

CONCLUSION

• Men with early prostate cancer have clear reasons for making decisions about treatment. Overall, patients were satisfied with the treatment and indicated that despite different reasons for choosing treatment, they would make the same choice again.
Adult Language Learning After Minimal Exposure to an Unknown Natural Language
Authors: Gullberg Marianne , Roberts Leah , Dimroth Christine , Veroude Kim , Indefrey Peter
Published: November 2010

Despite the literature on the role of input in adult second‐language (L2) acquisition and on artificial and statistical language learning, surprisingly little is known about how adults break into a new language in the wild. This article reports on a series of behavioral and neuroimaging studies that examine what linguistic information adults can extract from naturalistic but controlled audiovisual input in an unknown and typologically distant L2 after minimal exposure (7–14 min) without instruction or training. We tested the stepwise development of segmental, phonotactic, and lexical knowledge in Dutch adults after minimal exposure to Mandarin Chinese and the role of item frequency, speech‐associated gestures, and word length at the earliest stages of learning. In an exploratory neural connectivity study we further examined the neural correlates of word recognition in a new language, identifying brain regions whose connectivity was related to performance both before and after learning. While emphasizing the complexity of the learning task, the results suggest that the adult learning mechanism is more powerful than is normally assumed when faced with small amounts of complex, continuous audiovisual language input.
The Role of Linguistic Input in the First Hours of Adult Language Learning
Authors: Rast Rebekah
Published: November 2010

In the field of SLA, the dominant view of the starting point of SLA holds that the properties of the learner's first language (L1) grammar form the basis for the initial state of interlanguage development. It is assumed therefore that second‐language (L2) input processing happens through the lens of the L1 and that the perception of a discrepancy between the configuration of the L1 grammar and the L2 input triggers a restructuring of the developing system. This article takes a different approach to the analysis of the earliest stages of language learning. Based on results from an empirical study of the linguistic input (Polish) addressed to adult learners (French native speakers) in the first seconds, minutes, and hours of exposure to a novel target language as well as learners’ analysis of this input, it is argued that learners use a combination of knowledge stores, including but not limited to their L1 knowledge, to process the novel target language input to which they are exposed.
Short‐Term Grammatical Plasticity in Adult Language Learners
Authors: Davidson D. J.
Published: November 2010

This overview describes recent work on certain electrophysiological correlates of grammar learning in adults. Electrophysiology is potentially useful for sentence processing research related to learning not only because it has the temporal resolution to observe event‐related potential (ERP) responses to individual words as they appear within a sentence or a phrase but also for the behavioral classification occurring on the same trials. A classroom‐based longitudinal approach, well known from earlier research, is first described, in which a magnetoelectroencephalogram (MEG) is recorded periodically while students acquire knowledge from a course outside the laboratory. A short‐term learning design is also described, in which learners classify phrases while an electroencephalogram (EEG) is recorded. The main observation of this work is that short‐term changes in several ERP components can be seen in adult learners using conventional EEG or MEG recordings and that these short‐term changes are potentially diagnostic of learning mechanisms. The results, although preliminary in many respects, suggest that a productive direction for future research might be to examine the dynamics of electrophysiological responses and behavior at multiple time scales during grammar learning.
Birth Preferences that Deviate from the Norm in Sweden: Planned Home Birth versus Planned Cesarean Section
Authors: Hildingsson Ingegerd , Rådestad Ingela , Lindgren Helena
Published: November 2010

Abstract:  Background:  Opting for a home birth or requesting a cesarean section in a culture where vaginal birth in a hospital is the norm challenges the health care system. The aim of this study was to compare background characteristics of women who chose these very different birth methods and to see how these choices affected factors of care and the birth experience.

Methods:  This descriptive study employed a secondary data analysis of a sample of women who gave birth from 1997 to 2008, including 671 women who had a planned home birth and 126 women who had a planned cesarean section based on maternal request. Data were collected by means of questionnaires. Logistic regression with crude and adjusted odds ratios (OR) with a 95 percent confidence interval (95% CI) was calculated.

Results:  Women with a planned home birth had a higher level of education (OR: 2.3; 95% CI: 1.5–3.6), were less likely to have a high body mass index (OR: 0.1; 95% CI: 0.01–0.6), and were less likely to be smokers (OR: 0.2; 95% CI: 0.1–0.4) when compared with women who had planned cesarean sections. When adjusted for background variables, women with a planned home birth felt less threat to the baby’s life during birth (OR: 0.1; 95% CI: 0.03–0.4), and were more satisfied with their participation in decision making (OR: 6.0; 95% CI: 3.3–10.7) and the support from their midwife (OR 3.9; 95% CI: 2.2–7.0). They also felt more in control (OR: 3.3; 95% CI: 1.6–6.6), had a more positive birth experience (OR: 2.9; 95% CI: 1.7–5.0), and were more satisfied with intrapartum care (OR: 2.3; 95% CI: 1.3–4.1) compared with women who had a planned cesarean section on maternal request.

Conclusions:  Women who planned a home birth and women who had a cesarean section based on maternal request are significantly different groups of mothers in terms of sociodemographic background. In a birth context that promotes neither home birth nor cesarean section without medical reasons, we found that those women who had a planned home birth felt more involvement in decision making and had a more positive birth experience than those who had a requested, planned cesarean section. (BIRTH 37:4 December 2010)
Effects of Guided Imagery on Blood Pressure in Pregnant Women with Hypertension: A Pilot Randomized Controlled Trial
Authors: Moffatt Faith Wight , Hodnett Ellen , Esplen Mary Jane , Watt‐Watson Judy
Published: November 2010

Abstract:  Background:  Hypertension occurs in nearly 10 percent of pregnancies, and is associated with higher risk of infant and maternal morbidity and mortality than in normal pregnancies. Previous studies have suggested that relaxation therapies reduce blood pressure in nonpregnant adults. The objectives of this pilot randomized trial were to provide preliminary evidence of whether relaxation by means of guided imagery would reduce blood pressure in hypertensive pregnant women, and to assess the feasibility of a larger trial.

Methods:  A total of 69 pregnant women with hypertension were randomized to periods of guided imagery or of quiet rest, twice daily for 4 weeks or until delivery, whichever came first. Daytime ambulatory mean arterial pressure, systolic and diastolic blood pressure, and anxiety were measured weekly for up to 4 weeks.

Results:  Women allocated to guided imagery had lower mean arterial pressure elevations over time than those allocated to quiet rest (guided imagery: M = 1.58 mmHg, SD = 7.63; quiet rest: M = 5.93 mmHg, SD = 6.55; t = 2.36, p = 0.02). However, when adjusted for baseline mean arterial pressure and gestation, the effect was not significant (p = 0.14). Numbers of women prescribed antihypertensive medication postrandomization were similar (guided imagery: n = 16; quiet rest: n = 13, χ2 = 0.74, p = 0.46). There was also no evidence of an effect on women’s anxiety. Nearly 90 percent (n = 26) of the guided imagery group indicated that they would use it again.

Conclusions:  Further rigorous study is warranted to determine effects of guided imagery on maternal blood pressure and perinatal health outcomes. (BIRTH 37:4 December 2010)
Issuance Decisions and Strategic Focus: The Case of Long‐Term Care Insurance
Authors: McShane Michael K. , Cox Larry A.
Published: November 2010

Abstract

Increasing costs of long‐term care are placing ever greater burdens on state and federal budgets, yet private long‐term care insurance remains a relatively minor financing vehicle. Although many researchers provide rationales for the limited private market, some life–health insurers have forged ahead into this relatively new and risky line of business. We investigate what makes these insurers different and whether managers are following a diversification or strategic focus strategy. We find that strategic focus is a consistently important factor and that managers' participation and volume decisions are made independently.
A Cross‐National Study of Government Social Insurance as an Alternative to Tort Liability Compensation
Authors: Kerr Dana A. , Ma Yu‐Luen , Schmit Joan T.
Published: November 2010

Abstract

Litigation rates in the United States have long been considered out of proportion with the remainder of the world, leading to a good deal of economic research trying to understand the causes. Much of that literature has focused on lawyer compensation rules and availability of general damage awards. Another possible reason for differences in national litigation rates is the relative generosity of government social programs. Using a sample of 24 countries over a 12‐year period, we test the relationship between the size of government social program payments and liability costs as measured by liability insurance premiums, and find a strong negative relationship, controlling for income, accident rates, and a variety of other factors.
The Term Structure of Reserve Durations and the Duration of Aggregate Reserves
Authors: Tsai Chenghsien
Published: November 2010

Abstract

Estimating the duration gap of a life insurer demands the knowledge on the durations of liabilities and assets. The literature analyzed the durations of assets extensively but rendered limited analyses on the durations of insurance liabilities. This article calculated the reserve durations for individual policies and estimated the duration of the aggregate reserves. The results showed that the duration of the policy reserve might be negative and/or have a large figure. They further revealed an interesting pattern of the reserve duration with respect to the policy's time to maturity. A term structure with abnormal durations, however, does not result in an abnormal duration of the aggregate reserves.
Comparison of cerebral activity during teeth clenching and fist clenching: a functional magnetic resonance imaging study
Authors: Iida T. , Kato M. , Komiyama O. , Suzuki H. , Asano T. , Kuroki T. , Kaneda T. , Svensson P. , Kawara M.
Published: November 2010

Iida T, Kato M, Komiyama O, Suzuki H, Asano T, Kuroki T, Kaneda T, Svensson P, Kawara M. Comparison of cerebral activity during teeth clenching and fist clenching: a functional magnetic resonance imaging study.
 
Eur J Oral Sci 2010; 118: 635–641. © 2010 Eur J Oral Sci

Using functional magnetic resonance imaging (fMRI), we compared the cerebral activity during bilateral light fist‐clenching and light‐teeth clenching to provide more information on the central processing mechanisms underlying awake bruxism. Fourteen subjects participated in our study. Statistical comparisons were used to identify brain regions with significant activation in the subtraction of light fist clenching and light teeth clenching activity minus baseline. Participants also evaluated the perceived effort of clenching for each task, using a visual analogue scale of 0–100, after fMRI was performed. Bilateral light fist‐clenching significantly activated the bilateral sensorimotor cortex, while light teeth‐clenching was significantly associated with activation of the bilateral sensorimotor cortex, supplementary motor area, dorsolateral prefrontal cortex, and posterior parietal cortex. The VAS scores for fist clenching and teeth clenching were not significantly different. As light teeth‐clenching activates a more extensive cortical network compared with light fist‐clenching, we suggest that the teeth clenching may induce a more complex cerebral activity compared with the performance of a hand motor task. The clinical significance of these findings remains unknown but could perhaps be related to the propensity to trigger awake bruxism.
Amisulpride‐Induced Seizurogenic Effect: A Potential Role of Opioid Receptor‐Linked Transduction Systems
Authors: Rehni Ashish K. , Singh Thakur Gurjeet , Chand Prem
Published: November 2010

Abstract: This study was designed to investigate the role of opioid receptors, gamma‐aminobutyric acid (GABA) receptors, mast cells and histamine receptors (H1subtype) in the seizurogenic effect of amisulpride on mice. A single injection of amisulpride (180 mg/kg) was employed to evaluate the seizurogenicity of the drug in mice. Seizures were assessed in terms of a composite seizure severity score (SSS), time of the onset of straub‐like tail, onset of jerky movements of whole body, convulsions and death. Amisulpride administration (180 mg/kg) induced a significant pro‐convulsant effect in mice as measured in terms of the SSS (21.12 ± 2.71) and a significant decrease in the time latency of the onset of straub‐like tail (132.45 ± 12.31), jerky movements of whole body (153.28 ± 14.12), convulsions (184.97 ± 13.11) and death (100%). Moreover, prior administration of naloxone, cetrizine, sodium cromoglycate and gabapentin, respectively, attenuated this seizurogenic activity that amisulpride exerted on mice (p < 0.05). Therefore, it may be suggested that amisulpride exerts a seizurogenic effect on mice possibly via an opioid receptor activation‐dependent release of histamine from the mast cells and a simultaneous inhibition of GABA release.
The yoga of the Cassels–Tate pairing
Authors: Fisher Tom , Schaefer Edward F. , Stoll Michael
Published: November 2010

Cassels has described a pairing on the 2-Selmer group of an elliptic curve which shares some properties with the Cassels–Tate pairing. In this article, we prove that the two pairings are the same.
Ca2+‐regulated, neurosecretory granule channel involved in release from neurohypophysial terminals
Authors: Yin Yong , Dayanithi Govindan , Lemos José R.
Published: November 2010

Ion channels from bovine neurohypophysial secretory granules (NSG) were incorporated into artificial lipid bilayers. Specific antibodies against identified synaptic vesicle proteins were tested on such incorporated channel activity and on peptide release from rat permeabilized neurohypophysial terminals. Both the NSG cation channel and Ca2+‐dependent release were inhibited by only SY‐38, a monoclonal antibody directed against the C‐terminus of synaptophysin. SY‐38 and Ca2+ altered both the gating and conductance of the NSG cation channel, but in opposite ways. The close correlation between SY‐38 effects on Ca2+‐dependent channel activity and release leads us to conclude that this synaptophysin‐like NSG channel is directly involved in peptide secretion from these central nervous system terminals.
On Controlling an Uncertain System With Polynomial Chaos and H2 Control Design
Authors: Templeton Brian A. , Cox David E. , Kenny Sean P. , Ahmadian Mehdi , Southward Steve C.
Published: November 2010

This paper applies the H2 norm along time and parameter domains. The norm is related to the probabilistic H2 problem. It is calculated using polynomial chaos to handle uncertainty in the plant model. The structure of expanded states resulting from Galerkin projections of a state space model with uncertain parameters is used to formulate cost functions in terms of mean performances of the states, as well as covariances. Also, bounds on the norm are described in terms of linear matrix inequalitys. The form of the gradient of the norm, which can be used in optimization, is given as a Lyapunov equation. Additionally, this approach can be used to solve the related probabilistic LQR problem. The legitimacy of the concept is demonstrated through two mechanical oscillator examples. These controllers could be easily implemented on physical systems without observing uncertain parameters.
Lithium-Ion Battery State of Charge and Critical Surface Charge Estimation Using an Electrochemical Model-Based Extended Kalman Filter
Authors: Di Domenico Domenico , Stefanopoulou Anna , Fiengo Giovanni
Published: November 2010

This paper presents a numerical calculation of the evolution of the spatially resolved solid concentration in the two electrodes of a lithium-ion cell. The microscopic solid concentration is driven by the macroscopic Butler–Volmer current density distribution, which is consequently driven by the applied current through the boundary conditions. The resulting, mostly causal, implementation of the algebraic differential equations that describe the battery electrochemical principles, even after assuming fixed electrolyte concentration, is of high order and complexity and is denoted as the full order model. The full order model is compared with the results in the works of Smith and Wang (2006, “Solid-State Diffusion Limitations on Pulse Operation of a Lithium-Ion Cell for Hybrid Electric Vehicles,” J. Power Sources, 161, pp. 628–639) and Wang et al. (2007 “Control oriented 1D Electrochemical Model of Lithium Ion Battery,” Energy Convers. Manage., 48, pp. 2565–2578) and creates our baseline model, which will be further simplified for charge estimation. We then propose a low order extended Kalman filter for the estimation of the average-electrode charge similarly to the single-particle charge estimation in the work of White and Santhanagopalan (2006, “Online Estimation of the State of Charge of a Lithium Ion Cell,” J. Power Sources, 161, pp. 1346–1355) with the following two substantial enhancements. First, we estimate the average-electrode, or single-particle, solid-electrolyte surface concentration, called critical surface charge in addition to the more traditional bulk concentration called state of charge. Moreover, we avoid the weakly observable conditions associated with estimating both electrode concentrations by recognizing that the measured cell voltage depends on the difference, and not the absolute value, of the two electrode open circuit voltages. The estimation results of the reduced, single, averaged electrode model are compared with the full order model simulation.
Comparing Time Histories for Validation of Simulation Models: Error Measures and Metrics
Authors: Sarin H. , Kokkolaras M. , Hulbert G. , Papalambros P. , Barbat S. , Yang R.-J.
Published: November 2010

Computer modeling and simulation are the cornerstones of product design and development in the automotive industry. Computer-aided engineering tools have improved to the extent that virtual testing may lead to significant reduction in prototype building and testing of vehicle designs. In order to make this a reality, we need to assess our confidence in the predictive capabilities of simulation models. As a first step in this direction, this paper deals with developing measures and a metric to compare time histories obtained from simulation model outputs and experimental tests. The focus of the work is on vehicle safety applications. We restrict attention to quantifying discrepancy between time histories as the latter constitute the predominant form of responses of interest in vehicle safety considerations. First, we evaluate popular measures used to quantify discrepancy between time histories in fields such as statistics, computational mechanics, signal processing, and data mining. Three independent error measures are proposed for vehicle safety applications, associated with three physically meaningful characteristics (phase, magnitude, and slope), which utilize norms, cross-correlation measures, and algorithms such as dynamic time warping to quantify discrepancies. A combined use of these three measures can serve as a metric that encapsulates the important aspects of time history comparison. It is also shown how these measures can be used in conjunction with ratings from subject matter experts to build regression-based validation metrics.
Comparison of Linear, Nonlinear, Hysteretic, and Probabilistic Models for Magnetorheological Fluid Dampers
Authors: Sandu Corina , Southward Steve , Richards Russell
Published: November 2010

Magnetorheological (MR) fluid dampers have a semicontrollable damping force output that is dependent on the current input to the damper, as well as the relative velocity. The mechanical construction, fluid properties, and embedded electromagnet result in a dynamic damper response. This study evaluates four modeling approaches with respect to predicting the multi-input single-output behavior of an experimental MR damper when the inputs are band-limited random signals typically encountered in primary suspension applications. The first two models in this study are static in the sense that there is a unique output for any given set of inputs and no dynamics is present in either model. The third model incorporates a dynamic filter with the nonlinear model to exhibit hysteretic effects, which are known to exist in actual MR dampers. The fourth model is probabilistic and illustrates the dynamic nature of an actual MR damper. The results of this study clearly show the importance of nonlinear and dynamic effects in magnetorheological damper response. This study also highlights the importance of characterizing magnetorheological dampers using excitation signals that are representative of an actual implementation.
Modeling and Analysis of Active Differential Dynamics
Authors: Deur Joško , Ivanović Vladimir , Hancock Matthew , Assadian Francis
Published: November 2010

Active differentials are used to improve the overall performance of traction control and vehicle dynamics control systems. This paper presents the development of a unified mathematical model of active differential dynamics using the bond graph modeling technique. The study includes active limited slip differential and various common types of torque vectoring differentials. Different levels of model complexity are considered, starting from a second-order model with lumped input and output inertia toward higher-order models including the gear inertia and half-shaft compliance. The model is used for a theoretical analysis of drivability and time response characteristics of the active differential dynamics. The analysis is illustrated by simulation results.
Kalman Smoother Based Force Localization and Mapping Using Intravital Video Microscopy
Authors: Milutinović Dejan Lj. , Garg Devendra P.
Published: November 2010

Motility is an important property of immune system cells. It provides cells with the ability to perform their function not only at the right time but also at the right place. In this paper, we introduce the problem of modeling and estimating an effective force field directing cell movement by the analysis of intravital video microscopy. A computational approach is proposed for solving this problem without dealing with a parametrized spatial model of the field in order to avoid potential errors due to inaccurate spatial model assumptions. We consider the dynamics of cells similar to the dynamics of distributed agents typically used in the field of swarm robotics. The method utilizes a fixed-interval Kalman filter based smoother. Its application results in a map giving the intensity and direction of the effective force field. The results show that real-time video images are a source of data, enabling us to visualize intriguing spatiotemporal phenomena inside immune system organs. The proposed approach can fill the existing gap between contemporary technology and quantitative data analyses present in the field of biosystems.
Overspray and Interstage Fog Cooling in Gas Turbine Compressor Using Stage-Stacking Scheme—Part II: Case Study
Authors: Wang Ting , Khan Jobaidur R.
Published: November 2010

A stage-by-stage wet compression theory and algorithm have been developed for overspray and interstage fogging in the compressor. These theory and algorithm are used to calculate the performance of an eight-stage compressor under both dry and wet compressions. A 2D compressor airfoil geometry and stage setting at the mean radius are employed. Six different cases with and without overspray are investigated and compared. The stage pressure ratio enhances during all fogging cases as does the overall pressure ratio, with saturated fogging (no overspray) achieving the highest pressure ratio. Saturated fogging reduces specific compressor work, but increases the total compressor power due to increased mass flow rate. The results of overspray and interstage spray unexpectedly show that both the specific and overall compressor power do not reduce but actually increase. Analysis shows that this increased power is contributed by the increased pressure ratio and, for interstage overspray, “recompression” contributes to more power consumption. Also it is unexpected to see that air density actually decreases, instead of increases, inside the compressor with overspray. Analysis shows that overspray induces an excessive reduction in temperature that leads to an appreciable reduction in pressure, so the increment of density due to reduced temperature is less than the decrement of air density affected by reduced pressure as air follows the polytropic relationship. In contrast, saturated fogging results in increased density as expected. After the interstage spray, the local blade loading immediately showed a significant increase. Fogging increases axial velocity, flow coefficient, blade inlet velocity, incidence angle, and tangential component of velocity. The analysis also assesses the use of an average shape factor in the generalized compressor stage performance curve when the compressor stage information and performance map are not available. The result indicates that using a constant shape factor might not be adequate because the compressor performance map may have changed with wet compression. The results of nonstage-stacking simulation are shown to underpredict the compressor power by about 6% and the net gas turbine output by about 2% in the studied cases.
Benefit-Cost Analysis of Infrastructure Improvement for Derailment Prevention
Authors: Liu Xiang , Saat Mohd Rapik , Barkan Christopher P. L.
Published: November 2010

U.S. railroad accident rates have declined substantially since the 1980s; however, further improvement in train safety remains an important objective of the railroad industry. In this paper, we describe a framework developed to assess the cost-effectiveness of railroad infrastructure improvement to reduce railroad train accidents. Higher FRA track classes have been shown to be statistically correlated with lower accident rates, thereby indicating potential safety benefits. However, such infrastructure improvement also increases both capital and operating costs for track maintenance. We use accident data from the U.S. DOT Federal Railroad Administration (FRA) accident database and cost data from several recent U.S. railroad infrastructure maintenance projects presented in an FRA report to quantitatively evaluate the safety benefits and costs associated with infrastructure improvement decisions. Our model is intended to consider the trade-off between reduced accident rates and increased costs in evaluating railroad risk reduction strategies and operational decisions. The benefit-cost analysis framework is illustrated by considering the upgrade of track class 3 to class 4 in a hypothetical case study.
Analyses of Dynamic Behavior of Track Transition With Vehicle and Track Elements
Authors: Lei Xiaoyan , Zhang Bin , Rose Jerry G.
Published: November 2010

New types of vehicle and track elements are presented, by means of the finite element method, to establish a model for dynamic analysis of vehicle-track-subgrade coupling systems. The associated stiffness matrix, mass matrix and damping matrix for these two types of elements are deduced. Computational software is coded with Matlab. As an application example, dynamic behavior of track transition is investigated by the vehicle and the track elements. The influencing factors for the simulation include train speed, subgrade stiffness, and irregularity angles of track transition as well as the transition pattern. The computational results show that 1) Abrupt changes of the subgrade stiffness influence vertical acceleration of the rail and the wheel/rail contact force, and this influence increases with increases in train speed, 2) Both the irregularity angles of the track transition and the abrupt changes of the subgrade stiffness have significant effects on rail vertical acceleration and the wheel/rail contact force, with the peak value in this situation being greater than that generated by irregularity angles of the track transition or the abrupt changes of the subgrade stiffness, 3) Train speed, abrupt changes of the subgrade stiffness, and track transition irregularity angles have minor influences on the vertical acceleration of the vehicle due to the excellent behavior of vibration isolation resulting from the primary and the secondary suspension systems of the vehicle, 4) Transition pattern for irregularity of track transition has significant influences on the vehicle acceleration and the wheel/rail contact force, and the cosine transition is a much better indicator than the linear transition, and 5) Influences of the directions the train is moving on the dynamic behavior of the vehicle and the track are relatively insignificant.
KENTRACK, a Performance-Based Layered Elastic Railway Trackbed Structural Design and Analysis Procedure: A Tutorial
Authors: Rose Jerry G. , Agarwal Nithin K. , Brown Justin D. , Ilavala Neeharika
Published: November 2010

KENTRACK is a layer elastic finite element based computer program that can be utilized for a performance-based structural design and analysis of railway trackbeds. Kentrack was initially developed to analyze traditional all-granular layered trackbeds and asphalt layered trackbeds. The versatility was recently expanded to analyze trackbeds containing a combination of granular and asphalt layers. The principle factor in the analysis is to limit vertical compressive stresses on the subgrade. In addition, it is possible to consider the fatigue lives of the various layers relative to the effects of wheel loads, tonnages, environmental conditions and other factors. The service lives of the individual components of the trackbed are predicted by damage analysis for various combinations of traffic, tonnages, subgrade support, component layer properties and thicknesses. The latest version, KENTRACK 3.0, is coded in C#.NET, a popular computer language for achieving accuracy and efficiency. The graphical user interface in the KENTRACK 3.0 provides a technique to analyze trackbeds as structures. It is possible with KENTRACK 3.0 to select trackbed layers and associated thicknesses to satisfy roadbed and trackbed performance requirements. In addition, it is possible to performance-rank different track sectional designs based on the relative importance of the particular track section and track type. The types of roadbed and trackbed configurations are selected to meet each of the various performance ranks. The various steps involved in the calculations are highlighted during the tutorial phase of a sample design calculations and analysis.
Study on New Trends of Network and Transport Development of World Railways
Authors: Yang Xiaoli
Published: November 2010

Since the 21st century, the macro-background of the development of world railways has undergone great changes. As a transport mode with both stronger technical and economic comparative advantages and stronger sustainable comparative advantages, the development of railways in the world presents various trends. In this paper, based on the empirical and comparative research methods, the development of railways in different countries in recent years is reviewed and compared. New trends on the development of the railway network and transport are analyzed and discussed. Some interesting conclusions are obtained.