bluuebunny/crossref_metadata_2025 huggingface dataset:
Changes in thiol/disulfide homeostasis in juvenile idiopathic arthritis
Authors: Altinel Acoglu Esma , Erel Ozcan , Yazilitas Fatma , Bulbul Mehmet , Oguz Melahat Melek , Yucel Husniye , Karacan Can Demir , Senel Saliha
Published: March 2018

Background

The pathogenesis of juvenile idiopathic arthritis (JIA) remains unknown, but imbalance between the oxidant and antioxidant defense systems may play a role. Measuring thiols in plasma provides an indirect indication of antioxidative defense. The aim of the present study was to investigate the association between JIA and dynamic thiol/disulfide homeostatic status.

Methods

This case–control study involved 34 JIA patients and 30 age‐ and gender‐matched healthy controls. The patients were divided into subgroups according to Simplified Disease Activity Index (SDAI) score: active, SDAI > 3.3; remission, SDAI ≤ 3.3.

Results

Native thiol and total thiol were significantly lower in the JIA group than in the control group (P = 0.001). There was no significant difference in the disulfide/native thiol, disulfide/total thiol, and native thiol/total thiol ratios between the JIA and control groups (P > 0.05). Based on SDAI score, 22 JIA patients were in the remission subgroup, and 12 JIA patients were in the active subgroup. Native thiol and total thiol were significantly lower in the active JIA subgroup than in the remission subgroup (P = 0.001), but there were no significant differences in the other parameters. There was no significant difference in thiol and disulfide levels between systemic‐onset JIA and other JIA (P > 0.05).

Conclusions

Plasma thiol is lower in JIA patients, especially during periods of active disease, than in healthy controls, indicating that low thiol might be an important factor in the etiology of JIA and that antioxidant systems are negatively affected by inflammatory diseases, especially during periods of active disease.
Hyperbaric oxygen as a treatment modality in cyclophosphamide‐induced hemorrhagic cystitis
Authors: Kaur Dominder , Khan Shakila P. , Rodriguez Vilmarie , Arndt Carola , Claus Paul
Published: March 2018

Late‐onset HC is a well‐recognized complication associated with cyclophosphamide/acrolein‐induced toxicity. It poses a management challenge when hyperhydration and bladder irrigation do not result in clinical improvement as desired. The data regarding use of hyperbaric oxygen therapy (HBO2) as an early treatment modality in this clinical setting are limited. We present 2 cases, that were refractory to hyperhydration and bladder irrigation but responded to HBO2. They were treated with 20‐30 daily sessions over weekdays with 100% oxygen for 90 minutes at 2 atmospheric pressure units (2 atm). Both patients reported improved symptoms within the first 15 sessions, and hematuria diminished by 20 sessions. Hyperbaric oxygen is a less invasive, outpatient therapy that is effective for treatment of HC and is tolerated well by young patients.
Isolated cutaneous mucormycosis in a pediatric renal transplant recipient
Authors: Downie Mallory L. , Alghounaim Mohammad , Davidge Kristen M. , Yau Yvonne , Walsh Thomas J. , Pope Elena , Somers Gino R. , Waters Valerie , Robinson Lisa A.
Published: March 2018

Mucormycosis is a rare and potentially life‐threatening infection, typically affecting immunocompromised hosts. We report a case of an adolescent boy who developed primary isolated cutaneous mucormycosis in the early period following kidney transplantation. Surgical excision was performed using intraoperative fungal staining to obtain clear margins, followed by topical and systemic antifungal therapy. A skin graft was then applied to the excised area with good healing, and the patient made a full recovery.
Ofatumumab in post‐transplantation recurrence of a pediatric steroid‐resistant idiopathic nephrotic syndrome
Authors: Bernard Josselin , Bruel Alexandra , Allain‐Launay Emma , Dantal Jacques , Roussey Gwenaelle
Published: March 2018

Treatment of SRNS is a challenge. Antiproliferative agents and depleting antibodies have been reported to be effective. However, these agents are not always successful, and use of ofatumumab could provide a different treatment option. Our patient was diagnosed with a SRNS at 5 years of age. She developed ESRD, with FSGS. This was cause for a first renal transplantation. The NS relapsed, leading to loss of the graft, and a second renal transplantation was performed. Due to the recurrence of the NS, IAds were initiated and led to a complete remission. Our patient remained dependent on IAds, however, despite treatments with calcineurin inhibitors, corticosteroids, rituximab, and abatacept. Ofatumumab was introduced and led to a remission, thus allowing cessation of the IAd treatment. Another infusion of ofatumumab was administered 8 months after the last one, due to the recurrence of the NS and a renewed increase in B cells. Although it did not result in a complete remission, the proteinuria was stabilized in the absence of IAds. Ofatumumab may be an alternative treatment for post‐transplantation rituximab‐resistant SRNS, although this needs to be confirmed by further studies.
Characterization of 3‐Acetyl Chlorophyll a and 3‐Acetyl Protochlorophyll a Accommodated in the B800 Binding Sites of Photosynthetic Light‐Harvesting Complex 2 in the Purple Photosynthetic Bacterium Rhodoblastus acidophilus
Authors: Saga Yoshitaka , Miyagi Kanji
Published: March 2018

We present the detailed characterization on the reconstitution of two cyclic tetrapyrrole pigments that have the same substituents but differ in the degree of hydrogenation in the macrocycles from bacteriochlorophyll (BChl) a (7,8,17,18‐tetrahydroporphyrin) into the binding sites of B800 BChl a in light‐harvesting complex 2 (LH2) of purple photosynthetic bacteria. Both 3‐acetyl chlorophyll (Chl) a (17,18‐dihydroporphyrin) and 3‐acetyl protochlorophyll (PChl) a (porphyrin) were inserted into the B800‐binding pockets in LH2, indicating that these pockets allow alteration of the degree of hydrogenation in the cyclic tetrapyrroles. Redshifts of the Qy peak positions of 3‐acetyl (P)Chl a by insertion into the B800‐binding sites were smaller than that of BChl a. The relative Qy absorbance of 3‐acetyl (P)Chl a to B850 BChl a in the reconstituted proteins was significantly smaller than that of B800 BChl a in native LH2 in spite of their high occupancy in the B800‐binding sites. These are ascribable to the smaller dipole strengths of 3‐acetyl (P)Chl a. We also performed the coreconstitution of both 3‐acetyl Chl a and BChl a into the nine B800‐binding sites in LH2, indicating that the affinity of 3‐acetyl Chl a to the B800‐cavity was slightly higher than that of BChl a.
Assessment of recording bias in pregnancy studies using health care databases: An application to neurologic conditions
Authors: MacDonald Sarah C. , Hernán Miguel A. , McElrath Thomas F. , Hernández‐Díaz Sonia
Published: March 2018

Background

Pre‐existing conditions are imperfectly recorded in health care databases. We assessed whether pre‐existing neurologic conditions (epilepsy, multiple sclerosis [MS]) were differentially recorded in the presence of major obstetric outcomes (Caesarean delivery, preterm delivery, preeclampsia) in delivery records. We also evaluated the impact of differential recording on measures of frequency and association between the conditions and outcomes.

Methods

The 2011‐2014 Truven Health MarketScan® Commercial Claims Dataset was used to identify pregnancies. We calculated the relative recording of epilepsy and MS at delivery hospitalization compared with a 270‐day pre‐delivery window both overall and by the presence of major obstetric outcomes. We estimated risk ratios for the association between epilepsy and MS with the outcomes for each ascertainment window.

Results

We identified 909 065 pregnancies in women continuously enrolled from 270‐days before the delivery date. Of women with epilepsy identified in the pre‐delivery window, 73% had the condition coded at delivery. For MS, the proportion was 60%. MS recording at delivery did not vary by obstetric outcomes, however, delivery‐coded epilepsy was less likely confirmed in the pre‐delivery window in the presence of preeclampsia. Generally, the period of ascertainment did not meaningfully impact risk ratios, however, the risk ratio for preeclampsia associated with epilepsy was 1.67 (95% CI 1.47, 1.90) when epilepsy was ascertained at delivery and 1.26 (95% CI 1.07, 1.48) when epilepsy was ascertained in the pre‐delivery window (heterogeneity, P = .007).

Conclusions

Ascertainment of epilepsy and MS in delivery hospitalization records underestimated prevalence. However, the window of recording generally did not impact risk ratio estimates of associations with obstetric outcomes.
Effects of calcium and its interaction with phosphorus on the nutrient status and growth of three Lupinus species
Authors: Ding Wenli , Clode Peta L. , Clements Jon C. , Lambers Hans
Published: March 2018

Phosphorus (P)‐deficiency symptoms are known for Lupinus species grown in calcareous soil, but we do not know if this is due to high calcium (Ca) availability or low P availability in the soil. To address this problem, we explored both the effects of Ca and its interaction with P on nutrient status and growth of three Lupinus species. Two Ca‐sensitive genotypes (Lupinus angustifolius L. P26723 and Lupinus cosentinii Guss. P27225) and two Ca‐tolerant genotypes (L. angustifolius L. cv Mandelup and Lupinus pilosus Murr. P27440) were grown hydroponically at two P (0.1 and 10 μM) and three Ca (0.1, 0.6 and 6 mM) levels. Leaf symptoms and biomass were recorded, whole leaf and root nutrient concentrations were analysed, and leaf cellular P and Ca concentrations were determined. Phosphorus‐deficiency symptoms were only observed in the Ca‐sensitive genotypes. Among all the genotypes in this study, the Ca‐tolerant L. pilosus showed an ability to maintain stable leaf Ca and P concentrations whereas the Ca‐tolerant L. angustifolius cv Mandelup did not maintain a stable whole leaf Ca concentration, but maintained a low cytosolic Ca2+ concentration through effective Ca compartmentation. However, the two Ca‐sensitive genotypes, L. angustifolius P26723 and L. cosentinii, did not exhibit an ability to maintain a stable whole leaf Ca concentration or effectively compartmentalize Ca. Therefore, having the capacity to maintain a stable whole leaf Ca concentration or effectively compartmentalizing Ca in leaves are likely critical for Lupinus species to be Ca tolerant.
Limits of regulatory responsiveness:Democratic credentials of responsive regulation
Authors: Hong Seung‐Hun , You Jong‐sung
Published: March 2018

Responsiveness and accountability constitute the process of democratic representation, reinforcing each other. Responsiveness asks elected representatives to adopt policiesex antepreferred by citizens, while accountability consists of the people'sex postsanctioning of the representatives based on policy outcomes. However, the regulatory literature tends to interpret responsiveness narrowly between a regulator and regulatees: the regulator is responsive to regulatees’ compliance without considering broader public needs and preferences. Democratic regulatory responsiveness requires that the regulator should be responsive to the people, not just regulatees. We address this theoretical gap by pointing out the perils of regulatory capture and advancing John Braithwaite's idea of tripartism as a remedy. We draw out two conditions of democratic regulatory responsiveness from Philip Selznick – comprehensiveness and proactiveness. We then propose overlapping networked responsiveness based on indirect reciprocity among various stakeholders. This mechanism is the key to connecting regulatory responsiveness with accountability.
Online Information Sharing About Risks: The Case of Organic Food
Authors: Hilverda Femke , Kuttschreuter Margôt
Published: March 2018

Individuals have to make sense of an abundance of information to decide whether or not to purchase certain food products. One of the means to sense‐making is information sharing. This article reports on a quantitative study examining online information sharing behavior regarding the risks of organic food products. An online survey among 535 respondents was conducted in the Netherlands to examine the determinants of information sharing behavior, and their relationships. Structural equation modeling was applied to test both the measurement model and the structural model. Results showed that the intention to share information online about the risks of organic food was low. Conversations and email were the preferred channels to share information; of the social media Facebook stood out. The developed model was found to provide an adequate description of the data. It explained 41% of the variance in information sharing. Injunctive norms and outcome expectancies were most important in predicting online information sharing, followed by information‐related determinants. Risk‐perception‐related determinants showed a significant, but weak, positive relationship with online information sharing. Implications for authorities communicating on risks associated with food are addressed.
Deglacial record of palaeoearthquakes interpreted from mass transport deposits at three lakes near Rouyn‐Noranda, north‐western Quebec, Canada
Authors: Brooks Gregory R.
Published: March 2018

As part of an investigation of deglacial palaeoseismology within an intracratonic region of north‐eastern North America, the compilation of sub‐bottom acoustic profile surveys from study areas at Duparquet and Dufresnoy lakes, north‐western Quebec, Canada, produced thirteen and eight event horizon maps, respectively, depicting subaqueous mass transport deposits that are interbedded within Lake Ojibway glaciolacustrine varve deposits. Analysis of rhythmic couplets recovered in cores from both locations yielded varve ages with annual resolution for the event horizons relative to the regional Timiskaming varve series. These results are integrated with the published event horizon stratigraphy and varve chronology from nearby Lac Dasserat. The combined event horizon records for the three lakes overlap between varve years 1175 to 1625 (9395 to 8945 ± 200 cal year bp) and consist of 26 event horizons. Fifteen event horizons are inferred to be evidence of 11 palaeoearthquakes at qualitative levels of interpretative confidence varying from high to low. The palaeoearthquake interpretations and assessments of interpretative confidence are made from weightings of the event horizon signatures and, where possible, evidence supporting a stratigraphic footprint extending beyond a given study area. Occurring over a 450 varve year period when rapid crustal uplift was still underway, 11 interpreted palaeoearthquakes happened at an average rate of every ca 40 years. Relative to a published minimum threshold magnitude for generating a recognizable geomorphic signature, this average rate of occurrence exceeds the modern return period by two orders of magnitude. The palaeoearthquakes probably occurred within a period of elevated seismicity associated with rapid crustal unloading during deglaciation.
Type 1 innate lymphoid cell aggravation of atherosclerosis is mediated through TLR4
Authors: Wu C. , He S. , Liu J. , Wang B. , Lin J. , Duan Y. , Gao X. , Li D.
Published: March 2018

ILC populations elaborate a similar cytokine expression pattern with helper T cell subsets Th1, Th2 and Th17. Recent studies indicate that CD25+ILC2 could alleviate atherosclerosis by altering lipid metabolism, whereas the depletion of CD90‐expressing ILCs had no influence on atherosclerosis. Thus, these findings raise the question of whether ILC1 cells react on atherosclerosis. Hence, our group attempted to explore the role of ILC1 cells in atherosclerosis. We found that ILC1 cells have a high Th1‐like gene expression of T‐bet and IFN‐γ, which is distinct from ILC2, ILC3 or conventional NK (cNK) cells. Moreover, atherosclerotic lesions were greatly reduced in ApoE−/−Rag1−/− mice treated with anti‐NK1.1 mAbs for depleting ILC1 cells (ILC1+cNK cells), compared to ApoE−/−Rag1−/− mice treated with anti‐IL‐15R mAbs for depleting cNK cells, and these effects could be fully rescued through the adoptive transfer of ILC1 cells sorted from the spleen of ApoE−/−TLR4+/+ mice into ApoE−/−Rag1−/− mice treated with anti‐NK1.1 mAbs. However, the adoptive transfer of ILC1 cells sorted from the spleen of ApoE−/−TLR4−/− mice into ApoE−/−Rag1−/− mice treated with anti‐NK1.1 mAbs blocked the progression of atherosclerosis, indicating that the pro‐atherosclerotic role of ILC1 cells is dependent on TLR4. Furthermore, oxLDL‐induced increase in IFN‐γ expression from ApoE−/− ILC1 cells was correlated with the decrease in BACH2 expression. Taken together, ILC1 cells exist in atherosclerosis and aggravate atherosclerosis via increasing pro‐inflammatory cytokine expression in a TLR4/BACH2‐dependent manner.
Late Merge and Phases for Anti‐C‐Command Requirements
Authors: Abe Jun
Published: March 2018

In this article, I propose a unified explanation for the argument–adjunct asymmetries that have been observed regarding two seemingly unrelated anti‐c‐command requirements: (i) condition C and (ii) the anti‐c‐command requirement on argument ellipsis, observed in Abefor null arguments in Japanese. I argue that these asymmetries are best explained by the mechanism of late merge of adjuncts proposed by Lebeaux () with a derivational definition of c‐command à la Epstein (). Furthermore, I argue that the timing of late merge of adjuncts is regulated by phase theory in the way that adjuncts may be merged no later than completion of relevant operations at the phase domains they belong to.
Prospective monitoring of adenovirus infection and type analysis after allogeneic hematopoietic cell transplantation: A single‐center study in Korea
Authors: Kang Ji‐Man , Park Ki‐Sup , Kim Jong Min , Huh Hee Jae , Ki Chang‐Seok , Lee Nam Yong , Yoo Keon Hee , Sung Ki Woong , Koo Hong‐Hoe , Kim Yae‐Jean
Published: March 2018

Background

Epidemiologic studies of human adenovirus (HAdV) in allogeneic hematopoietic cell transplantation (HCT) recipients have been conducted mostly in European countries where HAdV 2 (species C) has been most prevalent in the community. The main objective of this study was to investigate the epidemiology and the characteristics of HAdV infection in Korean allogeneic HCT recipients (<19 years).

Methods

In a prospective study from April 2012 to September 2015, HAdV in blood, urine, and stool specimens were monitored weekly from transplantation to day 100 or after if clinically suspected. HAdV infection was defined as positive HAdV PCR result in any specimens regardless of symptoms.

Results

A total of 1734 specimens were collected from 57 consecutively enrolled recipients. The cumulative incidence of HAdV infection at day 100, and 1 year was 10%, and 20%, and the incidence of viremia was 2% and 6%, respectively. The median onset time from HCT to viremia was 221 days (range, 7‐596 days). All viremia cases were caused by only HAdV 3 (species B), whereas several types were detected in stool. Among patients with HAdV infection, lower absolute lymphocyte counts and extensive chronic graft‐vs‐host disease were associated with viremia (P = .028 and P = .006, respectively).

Conclusions

Compared to western studies, this study demonstrated a lower incidence and delayed onset of HAdV infections and HAdV 3 was most prevalent in Korea.
Voriconazole concentration is inversely correlated with corticosteroid usage in immunocompromised patients
Authors: Imataki Osamu , Yamaguchi Kazunori , Uemura Makiko , Fukuoka Noriyasu
Published: March 2018

Background

Voriconazole (VRCZ) is a broad‐spectrum antifungal agent that can be administered both orally and intravenously. A high level of intra‐ and interindividual variability in serum drug therapeutic concentrations has been reported. We analyzed the influence of corticosteroid use on serum VRCZ concentration by assessing the correlation between corticosteroid dose and VRCZ trough level.

Methods

Immunocompromised patients treated with VRCZ with or without corticosteroid use from June 2010 to March 2017 (6 years and 8 months) were reviewed in our institute. VRCZ and the corticosteroids were administered orally or intravenously. Corticosteroid treatment was considered as “concurrent” only if it was administered within 3 days before or after the initiation of VRCZ. All corticosteroids were converted to a prednisolone‐based dosage according to their anti‐inflammatory effect (relative glucocorticoid activity). VRCZ concentration was measured at the trough point on the day of steady state.

Results

A total of 85 samples were obtained from 38 patients. The medical records of 23 women and 15 men, with a median age of 61 years (range: 35‐86), were reviewed. Twenty‐one patients (55.3%, 21/38) received chemotherapy, and 28 (73.7%, 28/38) received corticosteroid therapy. The average and median daily doses of corticosteroids were 59.2 and 89.8 mg, respectively (range: 0.714‐377). VRCZ concentration was inversely correlated with corticosteroid dose (r = −.26). The VRCZ concentration was significantly decreased in the corticosteroid user compared to nonuser (P = .013). We evaluated the association of VRCZ concentration and corticosteroid dose in 3 patients among our cohorts for whom more than 5 points of data were available. Intraindividual analysis revealed the trough level of VRCZ concentration decreased as the corticosteroid dose increased. The patients’ underlying diseases were hematological diseases (n = 25) and immunological diseases (n = 13). Among accrual patients, no patients were undergoing stem cell transplantation, and no patients were treated with known confounders such as calcineurin inhibitors or phenytoin.

Conclusions

VRCZ might be metabolized by an enzyme induced by corticosteroid treatment; therefore, intraindividual variation in VRCZ metabolism should be considered prior to concurrent treatment, especially for patients with hematological malignancies treated with corticosteroids.
Confirmed microsporidial graft infection in a HIV‐negative renal transplant recipient: A case report and review of the literature
Authors: Brown M. , Longano A. , Dendle C. , Polkinghorne K.R. , Kanellis J.
Published: March 2018

Microsporidia are intracellular organisms most commonly known to cause opportunistic infection in patients with human immunodeficiency virus (HIV). There have been several case reports of infection in solid organ and bone marrow transplant recipients. Here, we report a case of a non‐HIV–infected renal transplant patient with microsporidiosis of the renal tract associated with acute graft dysfunction. We also review the literature of 12 previously reported cases of microsporidiosis in patients with renal transplants who had described graft involvement. We review the pattern of illness as well as the common renal biopsy features when microsporidial infection is associated with renal graft infection.
Paradoxical immune reconstitution inflammatory syndrome associated with disseminated tuberculosis infection in an unrelated donor cord blood transplant recipient
Authors: Lee Yeon Joo , Bacchus Melissa , Schmidt Elizabeth , Chawla Mohit , Barker Juliet N. , Papanicolaou Genovefa A.
Published: March 2018

Tuberculosis (TB) is an infrequent infection after hematopoietic cell transplant (HCT), with associated mortality up to 30%. The utility of universal screening for latent TB in HCT candidates is controversial due to the lack of sensitive screening tests. We describe a case of disseminated TB infection complicated by immune reconstitution inflammatory syndrome in an adult double unit umbilical cord blood transplant recipient who originated from the United Arab Emirates.
Shoot phytochrome B modulates reactive oxygen species homeostasis in roots via abscisic acid signaling in Arabidopsis
Authors: Ha Jun‐Ho , Kim Ju‐Heon , Kim Sang‐Gyu , Sim Hee‐Jung , Lee Gisuk , Halitschke Rayko , Baldwin Ian T. , Kim Jeong‐Il , Park Chung‐Mo
Published: March 2018

Underground roots normally reside in darkness. However, they are often exposed to ambient light that penetrates through cracks in the soil layers which can occur due to wind, heavy rain or temperature extremes. In response to light exposure, roots produce reactive oxygen species (ROS) which promote root growth. It is known that ROS‐induced growth promotion facilitates rapid escape of the roots from non‐natural light. Meanwhile, long‐term exposure of the roots to light elicits a ROS burst, which causes oxidative damage to cellular components, necessitating that cellular levels of ROS should be tightly regulated in the roots. Here we demonstrate that the red/far‐red light photoreceptor phytochrome B (phyB) stimulates the biosynthesis of abscisic acid (ABA) in the shoots, and notably the shoot‐derived ABA signals induce a peroxidase‐mediated ROS detoxification reaction in the roots. Accordingly, while ROS accumulate in the roots of the phyb mutant that exhibits reduced primary root growth in the light, such an accumulation of ROS did not occur in the dark‐grown phyb roots that exhibited normal growth. These observations indicate that mobile shoot‐to‐root ABA signaling links shoot phyB‐mediated light perception with root ROS homeostasis to help roots adapt to unfavorable light exposure. We propose that ABA‐mediated shoot‐to‐root phyB signaling contributes to the synchronization of shoot and root growth for optimal propagation and performance in plants.
Pandora’s Net
Authors: Logan Brittany
Published: March 2018

This study analyses potential weaknesses of supervisory control and data acquisition (SCADA) systems and possible workarounds to safeguard the critical infrastructure. SCADA systems are the hardware and software that control and monitor infrastructure and industrial processes. In the world of energy, the industrial control systems monitoring the physical processes of machines are less tangible than the actual physical machines they control. One of the benefits of soft power is that it offers the ability to use coercive force and create confusion without using overt means. Disconnecting any unnecessary network connections and restricting personnel access to only essential programs will limit unwanted access to SCADA systems through backdoor networks. It has been recommended that the energy sector ought to implement back-up and defense-in-depth systems. The concept of a common computer language for SCADA has also been mentioned in the security community, but could come with challenges.
Human Supervised Control of a Humanoid Robot for Non-Conventional Emergency Response
Authors: Padir Taskin , Gennert Michael A. , Atkeson Christopher G.
Published: March 2018

This article presents work of a research & development effort that focuses on realizing effective human-supervised humanoid robot control for non-conventional emergency response. The devastation and dangerous operational environments caused by natural and man-made disasters have been the motivation for the DARPA Robotics Challenge (DRC). Humanoid robots have advantages for completing a wide variety of tasks in human environments such as opening doors, turning valves, operating power tools, traversing rough terrain and driving a vehicle. This article also discusses various approaches, results, and lessons learned. Meeting the requirements of the DRC tasks using an Atlas humanoid robot has been the main research and development effort. One of the lessons learnt is that providing effective and easy to use human-robot interfaces is critical. Since the DRC poses realistically challenging operating conditions for the human, the interfaces need to have sufficient autonomy to minimize human errors.
60 Years of Turbo Expo
Authors: Langston Lee S.
Published: March 2018

This article presents success and failure stories of turbo expo. For the first three score years, the International Gas Turbine Institute’s (IGTI) Turbo Expo has been the pre-eminent gas turbine conference. The IGTI Turbo Expo in June 2015 will be the 60th gathering—surely a record in longevity and vitality for a single technology conference. The inaugural all-gas turbine meeting had 25 exhibitors, 6 technical sessions with a total of 17 papers and an attendance of 750. On May 8–10, 1944, ASME’s 17th National Oil and Gas Power Conference was held in Tulsa. The technical program consisted of four sessions; three on diesel engine technology and one on the newly emerging gas turbine. As the international gas turbine community grew, the number of papers sponsored increased to the point that it was obvious a separate meeting was needed. Projects and services developed, produced, and financed by IGTI have increased since 1979, supported by a staff of five to seven. One of the global areas for booming markets – and future technology – is Asia. As a reflection of this, IGTI will be holding Turbo Expo 2016 in Seoul, South Korea.
Project Atlantis
Authors: Franchek Matthew A.
Published: March 2018

This paper explores the reach and use of subsea engineering. Subsea engineering presents many new challenges and opportunities for engineers from any discipline. The fundamental engineering challenges facing today’s ultra-deepwater oil and gas production reside under a new engineering discipline, the subsea engineer. Designing subsea systems for 30-year-long controllability, safety, maintenance, and real-time optimization are critical issues and present an open-ended problem. Safety is absolutely a primary focus on any subsea production system design. There must be multiple independent safety paths in place to isolate a producing well. The most common subsea safety system is located within the well. Pioneering work performed at the university of Houston provided mathematical relationships to predict the flow regime given gas and liquid velocities, including dispersed bubble flow, elongated bubble flow, slug flow, stratified flow, etc. There is an unexplored coupling between the transient multiphase flow and the heat transfer. The field of modeling multiphase transient transport is important to the subsea architecture design and real-time optimization of subsea production.
Heading for Deeper Waters
Authors: Kosowatz John
Published: March 2018

This article highlights the evolution and use of floating platforms in the field of offshore turbines. While floating platforms are not new – oil and gas producers have built very large tension-leg platforms and others for drilling and processing – wind turbines present different problems. Modeling tools have evolved to predict the response of a fully coupled wind turbine and its substructure. Keeping costs down is critical for offshore developers. DeepCwind’s semisubmersible platform is constructed of prestressed concrete and steel, the result of vigorous testing of a variety of potential designs. In shallow water, contractors can economically build a fixed platform and install the turbine and its tower. In deep water, floaters make more sense, although they are not small structures. Besides the tower, they must support at least 350 metric tons, the weight of the nacelle and rotor blades of a 6 MW Siemens direct-drive turbine, which the company claims are the lightest in class.
Polytropic Efficiency Calculations For Gas Turbines
Authors: Wettstein Hans E.
Published: March 2018

This article demonstrates various aspects of polytropic efficiency calculations method for performance simulation of gas turbines. A recursive algorithm for integrating the incremental classic definition can easily be derived in a manner that any equations of state v(p, T) can be used. The Constant Dissipation Rate Algorithm (CDRA) is recommended for all calculations of polytropic changes with elevated accuracy requirements but especially if high pressure or pronounced real gases are involved. All required formulas are indicated in the paper. There is also a simple test for the achievable convergence or accuracy included. The comparison of the CDRA with two conventional formulas indicates astonishing deviations even for dry air.
A Partial History of Water-Cooled Gas Turbines
Authors: Day William H.
Published: March 2018

This article focuses on the work done at GE from 1960s to the early 1980s. GE funded the project of developing a full pressure/full temperature model of the same size. Test facilities were also built and run to gather data on potential problems such as: long term effects of partial channel water cooling on erosion, corrosion, and deposition; water supply, distribution and collection in the outer casing; materials testing with contaminated fuels. The results of the Electric Power Research Institute (EPRI) program were sufficiently encouraging that GE and EPRI decided to advocate a bigger project to the US Department of Energy to demonstrate the concept in utility size components. GE dropped work on water cooling in the early 1980s. Part of the reason was concern of instabilities in the boiling water.
Surgical Performance Assessment
Authors: Kumar Suren , Ahmidi Narges , Hager Greg , Singhal Pankaj , Corso Jason , Krovi Venkat
Published: March 2018

This article focuses on human skill understanding in the context of surgical assessment and training which has enormous and immediate application potential to enhance healthcare delivery. Surgical procedural performance involves interplay of a highly dynamic system of inter-coupled perceptual, sensory, and cognitive components. Computer-Integrated Surgery systems are a quintessential part of modern surgical workflow owing to developments in miniaturization, sensors and computation. Robotic Minimally Invasive Surgery, and the engendered computer-integration, offers unique opportunities for quantitative computer-based surgical-performance evaluation. The skill evaluation metrics as discussed need a variety of sensory data that limits the application to very specific robotic devices. The ability to couple quantitative, validated and stable metrics for surgical performance would lead to improvements in assessment and subsequently, training methods. Cognitive assessment can now be extended to also include sensorimotor assessment, with capacity to monitor and track skill across time.
Harvard and Engineering Education
Authors: Florman Samuel C.
Published: March 2018

This article talks about a positive shift in engineering education and applied sciences in global educational institutions such as Harvard. In the past, students at universities such as Harvard suffered due to lack of emphasis on engineering education; however, this has changed now with funding from outside. The roots of engineering professionalization are to be found in France, where as early as 1675, the government organized a corps of military engineers to oversee construction of fortresses and harbors. In 1985, the academic year preceding Prince Charles’s condescending remarks, Harvard awarded only 38 undergraduate degrees in engineering science, plus six master’s degrees and eight doctorates. The boost in the funding for engineering programs brings hope for the students in Harvard at the least.
Underwater Vehicles Based on Biological Intelligence
Authors: Ayers Joseph
Published: March 2018

This article discusses various aspects of underwater vehicles based on biological intelligence. Recent advances in biomimetics have made it feasible to integrate underwater robots that capture the performance advantages of their animal model. In the biomimetic robots, neurons and synapses are represented as structures, and the equations for each element are updated asynchronously at discrete times in a run-time loop. Search vectors composed of a heading and a distance monitored by a compass and visual odometry can organize the autonomous behavior of the vehicles, and these supervisory commands can be transmitted to the vehicle via sonar by a human operator or random search algorithm. The biological intelligence system that is being researched and developed can mediate supervised reactive autonomy through neuronal integrative processes in networks. The networks of biological intelligence represent a viable alternative to the algorithms of artificial intelligence in the achievement of robotic autonomy.
Artificial Skin
Authors: Majidi Carmel
Published: March 2018

This article presents a brief overview of advent and future of the concept of artificial skin. Sensorized electronic skins are an essential element in wearable computing and co-robotic systems that engage in physical interaction with humans. Wearable computing is a rapidly growing sub-domain in the electronics industry and has the potential to transform how we work, play, get information, and interact with others. Due to its close connection to personal electronics and fashion, artificial skin technologies represent a good opportunity for science, technology, engineering, and math (STEM) outreach at the middle- and high-school levels. Wearable technology is a promising path to STEM education, since it is relevant to the daily experiences of teens and pre-teens, regardless of their social, cultural, and economic background. Middle-school students are an especially appropriate target, since they have adequate intellectual preparation for hardware prototyping but are still at the earliest stages of developing their academic interests.
The Design of Input Shapers Which Eliminate Nonzero Initial Conditions
Authors: Newman Daniel , Hong Seong-Wook , Vaughan Joshua E.
Published: March 2018

Input shaping is widely used in the control of flexible systems due to its effectiveness and ease of implementation. Due to its open-loop nature, it is often overlooked as a control method in systems where parametric uncertainty or force disturbances are present. However, if the disturbances are known and finite in duration, their effect on the flexible mode can be approximated by formulating an initial condition control problem. With this knowledge, an input shaper can be designed, which cancels the initial oscillation, resulting in minimal residual vibration. By incorporating Specified Insensitivity robustness constraints, such shapers can be designed to ensure good performance in the presence of modeling uncertainty. This input shaping method is demonstrated through computer and experimental methods to eliminate vibration in actuator bandwidth-limited systems.
Benchmark for Numerical Models of Stented Coronary Bifurcation Flow
Authors: García Carrascal P. , García García J. , Sierra Pallares J. , Castro Ruiz F. , Manuel Martín F. J.
Published: March 2018

In-stent restenosis ails many patients who have undergone stenting. When the stented artery is a bifurcation, the intervention is particularly critical because of the complex stent geometry involved in these structures. Computational fluid dynamics (CFD) has been shown to be an effective approach when modeling blood flow behavior and understanding the mechanisms that underlie in-stent restenosis. However, these CFD models require validation through experimental data in order to be reliable. It is with this purpose in mind that we performed particle image velocimetry (PIV) measurements of velocity fields within flows through a simplified coronary bifurcation. Although the flow in this simplified bifurcation differs from the actual blood flow, it emulates the main fluid dynamic mechanisms found in hemodynamic flow. Experimental measurements were performed for several stenting techniques in both steady and unsteady flow conditions. The test conditions were strictly controlled, and uncertainty was accurately predicted. The results obtained in this research represent readily accessible, easy to emulate, detailed velocity fields and geometry, and they have been successfully used to validate our numerical model. These data can be used as a benchmark for further development of numerical CFD modeling in terms of comparison of the main flow pattern characteristics.
Computational Fluid Dynamics of Vascular Disease in Animal Models
Authors: Acuna Andrea , Berman Alycia G. , Damen Frederick W. , Meyers Brett A. , Adelsperger Amelia R. , Bayer Kelsey C. , Brindise Melissa C. , Bungart Brittani , Kiel Alexander M. , Morrison Rachel A. , Muskat Joseph C. , Wasilczuk Kelsey M. , Wen Yi , Zhang Jiacheng , Zito Patrick , Goergen Craig J.
Published: March 2018

Recent applications of computational fluid dynamics (CFD) applied to the cardiovascular system have demonstrated its power in investigating the impact of hemodynamics on disease initiation, progression, and treatment outcomes. Flow metrics such as pressure distributions, wall shear stresses (WSS), and blood velocity profiles can be quantified to provide insight into observed pathologies, assist with surgical planning, or even predict disease progression. While numerous studies have performed simulations on clinical human patient data, it often lacks prediagnosis information and can be subject to large intersubject variability, limiting the generalizability of findings. Thus, animal models are often used to identify and manipulate specific factors contributing to vascular disease because they provide a more controlled environment. In this review, we explore the use of CFD in animal models in recent studies to investigate the initiating mechanisms, progression, and intervention effects of various vascular diseases. The first section provides a brief overview of the CFD theory and tools that are commonly used to study blood flow. The following sections are separated by anatomical region, with the abdominal, thoracic, and cerebral areas specifically highlighted. We discuss the associated benefits and obstacles to performing CFD modeling in each location. Finally, we highlight animal CFD studies focusing on common surgical treatments, including arteriovenous fistulas (AVF) and pulmonary artery grafts. The studies included in this review demonstrate the value of combining CFD with animal imaging and should encourage further research to optimize and expand upon these techniques for the study of vascular disease.
Additive Manufacturing of Functionally Graded Material Objects: A Review
Authors: Zhang Binbin , Jaiswal Prakhar , Rai Rahul , Nelaturi Saigopal
Published: March 2018

Functionally graded materials (FGM) have recently attracted a lot of research attention in the wake of the recent prominence of additive manufacturing (AM) technologies. The continuously varying spatial composition profile of two or more materials affords FGM to possess properties of multiple different materials simultaneously. Emerging AM technologies enable manufacturing complex shapes with customized multifunctional material properties in an additive fashion. In this paper, we focus on providing an overview of research at the intersection of AM techniques and FGM objects. We specifically discuss FGM modeling representation schemes and outline a classification system to classify existing FGM representation methods. We also highlight the key aspects such as the part orientation, slicing, and path planning processes that are essential for fabricating FGM object through the use of multimaterial AM techniques.
Experimental and Numerical Investigation of Effusion Cooling Effectiveness of Combustion Chamber Liner Plates
Authors: Arjun C. K. , Jayakumar J. S. , Giridhara Babu Y. , Felix J.
Published: March 2018

This study aims to evaluate adiabatic and conjugate effusion cooling effectiveness of combustion chamber liner plate of gas turbines. Validation of the adiabatic model was done by comparing computational fluid dynamics (CFD) result with the experimental results obtained using the subsonic cascade tunnel facility available at Heat Transfer Lab of Council of Scientific and Industrial Research-National Aerospace Laboratories (CSIR-NAL). Computational simulation of the conjugate model is validated against published numerical results. Numerical simulation for the adiabatic cooling effectiveness is carried out for a 1:3 scaled up flat plate test geometry, while the actual flat plate geometry is considered for the conjugate cooling effectiveness analysis. The test plate has 11 rows of cooling holes, and the holes are arranged in staggered manner with each row containing eight holes. For both adiabatic and conjugate cases, the same mainstream conditions are maintained with the inlet temperature of 329 K, velocity of 20 m/s, density ratio 1.3. The coolant to mainstream blowing ratios (BRs) are maintained at 0.4, 1.15, and 1.6. The coolant temperature is 253 K with the flow rates are according to the BRs. Cooling effectiveness is obtained by using CFD simulation with ANSYS fluent package. From the comparison of adiabatic and conjugate results, it is found that conjugate model is giving superior cooling protection than the adiabatic model and effusion cooling effectiveness increases with increase in BR. Investigations on comparison of angle of injection holes show that, 30 deg model give maximum effusion cooling effectiveness as compared to 45 deg and 60 deg models.
Viscoelastic and Damage Model of Polyethylene Pipe Material for Slow Crack Growth Analysis
Authors: Zhang Yue , Luo Xiangpeng , Shi Jianfeng
Published: March 2018

Polyethylene (PE) pipe is widely used for oil and gas transportation. Slow crack growth (SCG) is the main failure mechanism of PE pipes. Current SCG resistance testing methods for PE pipes have significant drawbacks, including high cost, time-consuming, and uncertain reliability. Alternative method is in need to reduce the testing time and cost. In this paper, a numerical model is proposed by taking the viscoelastic and damage effect of PE material into account. The material behavior is described on the basis of linear viscoelastic integral constitutive model, along with the damage effect in effective configuration concept. A three-dimensional (3D) incremental form of a viscoelastic and damage model is derived and implemented by abaqus UMAT. It is found that the curve of tensile displacement versus time, as well as the curve of crack opening displacement (COD) versus time from numerical results fit well with those from the standard Pennsylvania Notch Test (PENT; ASTM 1473). Based on the proposed model, SCG failure process is analyzed, and the effects of damage parameters on SCG process are furtherly studied and discussed.
The Mechanism of Size-Based Particle Separation by Dielectrophoresis in the Viscoelastic Flows
Authors: Zhou Teng , Deng Yongbo , Zhao Hongwei , Zhang Xianman , Shi Liuyong , Woo Joo Sang
Published: March 2018

Viscoelastic solution is encountered extensively in microfluidics. In this work, the particle movement of the viscoelastic flow in the contraction–expansion channel is demonstrated. The fluid is described by the Oldroyd-B model, and the particle is driven by dielectrophoretic (DEP) forces induced by the applied electric field. A time-dependent multiphysics numerical model with the thin electric double layer (EDL) assumption was developed, in which the Oldroyd-B viscoelastic fluid flow field, the electric field, and the movement of finite-size particles are solved simultaneously by an arbitrary Lagrangian–Eulerian (ALE) numerical method. By the numerically validated ALE method, the trajectories of particle with different sizes were obtained for the fluid with the Weissenberg number (Wi) of 1 and 0, which can be regarded as the Newtonian fluid. The trajectory in the Oldroyd-B flow with Wi = 1 is compared with that in the Newtonian fluid. Also, trajectories for different particles with different particle sizes moving in the flow with Wi = 1 are compared, which proves that the contraction–expansion channel can also be used for particle separation in the viscoelastic flow. The above results for this work provide the physical insight into the particle movement in the flow of viscous and elastic features.