bluuebunny/crossref_metadata_2025 huggingface dataset:
What has happened in the last 50 years in immunology
Authors: Wong Melanie
Published: February 2015

Fifty years ago, in 1964, our understanding of the immune system was very rudimentary. Gell and Coombs had just described classes of hypersensitivity reactions, and Bruton had described and commenced immunoglobulin replacement in agammaglobulinaemia. The distinction between T and B cells was not identified and characterised until the 1960s and 1970s. This was followed by increasing recognition of T and B cell collaboration in immune responses and identification of significant immunodeficiencies. CD4 and CD8 T cells were only recognised in the 1970s and 1980s. We now know of five CD4 subsets; dysfunction of each is associated with different disorders. By 2014, advances in technology have enabled identification of the genetic basis of over 240 primary immunodeficiencies. Research into the gut microbiome and vitamin D holds promise for the understanding, treatment and prevention of autoimmune and allergic diseases. Immunoglobulin preparations for the treatment of antibody deficiencies improved with the development of preparations for intravenous then subcutaneous administration, giving patients choice and the ability for home‐based treatment, especially if experiencing infusion associated adverse effects. Newborn screening for severe combined immunodeficiency is a reality. Improvements in haemopoietic stem cell transplantation and now gene therapy, albeit still only available in the research setting, are improving long‐term survival in primary immunodeficiencies. Biologic therapeutic agents are improving the control of autoimmune disease but potentially leading to secondary immunodeficiency, increasing the risk of opportunistic infection and malignancy. It is an exciting time.
Abdominal examination
Authors: Kara Tonya , Evans Helen M
Published: February 2015

The four short cases in the Clinical Examination give the candidate the opportunity to demonstrate the skills developed during basic training, including tailoring the clinical examination to difficult settings, such as a child of a difficult age, a bored child or a child who needs winning over quickly. The abdominal short case gives the candidate a chance to show their general approach to children and their families as much as their skill in detecting ascites.
The effect of feeding on the pharmacokinetic variables of two commercially available formulations of omeprazole
Authors: Sykes B. W. , Underwood C. , McGowan C. M. , Mills P. C.
Published: February 2015

The objectives of this study were to investigate the impact of formulation (enteric coated and buffered) and feeding on pharmacokinetic variables associated with the oral administration of omeprazole in the horse. Six thoroughbred racehorses were studied in a crossover design. Each received 2 g of an enteric coated or buffered formulation in both the fed and fasted state. Plasma omeprazole concentrations were determined by UHPLC‐MS. The effects of feeding or formulation on AUC0‐inf_obs, half‐life, Tmaxor Cmaxwere not statistically significant. However, a wider‐than‐expected degree of variation was present and examination of the raw data suggests that an effect of feeding, wherein the bioavailability of omeprazole may be reduced in the fed animal, may be present. Further investigation in a larger population of animals to assess the factors that contribute to the wide degree of absorption observed is warranted.
Post‐fragmentation population structure in a cooperative breeding Afrotropical cloud forest bird: emergence of a source‐sink population network
Authors: Husemann M. , Cousseau L. , Callens T. , Matthysen E. , Vangestel C. , Hallmann C. , Lens L.
Published: February 2015

The impact of demographic parameters on the genetic population structure and viability of organisms is a long‐standing issue in the study of fragmented populations. Demographic and genetic tools are now readily available to estimate census and effective population sizes and migration and gene flow rates with increasing precision. Here we analysed the demography and genetic population structure over a recent 15‐year time span in five remnant populations of Cabanis's greenbul (Phyllastrephus cabanisi), a cooperative breeding bird in a severely fragmented cloud forest habitat. Contrary to our expectation, genetic admixture and effective population sizes slightly increased, rather than decreased between our two sampling periods. In spite of small effective population sizes in tiny forest remnants, none of the populations showed evidence of a recent population bottleneck. Approximate Bayesian modelling, however, suggested that differentiation of the populations coincided at least partially with an episode of habitat fragmentation. The ratio of meta‐Ne to meta‐Nc was relatively low for birds, which is expected for cooperative breeding species, while Ne/Nc ratios strongly varied among local populations. While the overall trend of increasing population sizes and genetic admixture may suggest that Cabanis's greenbuls increasingly cope with fragmentation, the time period over which these trends were documented is rather short relative to the average longevity of tropical species. Furthermore, the critically low Nc in the small forest remnants keep the species prone to demographic and environmental stochasticity, and it remains open if, and to what extent, its cooperative breeding behaviour helps to buffer such effects.
Candidaemia in a paediatric centre and importance of central venous catheter removal
Authors: Karadag‐Oncel Eda , Kara Ates , Ozsurekci Yasemin , Arikan‐Akdagli Sevtap , Cengiz Ali Bulent , Ceyhan Mehmet , Gur Deniz , Celik Melda , Ozkaya‐Parlakay Aslinur
Published: February 2015

The aim of this study is to identify differences in distribution of Candida species, resistance to antifungals and clinical outcome, as well as the identification of potential risk factors associated with candidaemia in children. We conducted a retrospective analysis in children ≤18 years with blood culture proven candidaemia identified between 2004 and 2012. Patients were divided into two groups (Group 1, <3 months, n = 51; Group 2, ≥3 months, n = 197) to identify any potential difference between the neonatal and early infantile periods in terms of risk factors and distribution of Candida species. A total of 248 distinct episodes of candidaemia were identified over the study period. The most frequently isolated Candida species were C. albicans (53.2%), followed by C. parapsilosis (26.2%), C. tropicalis (8.1%). Of the 248 episodes, 71 episodes (28.6%) resulted in death within 30 days from the onset of candidaemia. In Group 1, failure of central venous catheter (CVC) removal was found to be associated with a 20.5‐fold increase in mortality [95% CI (3.9, 106.5); P < 0.001], compared to a 5.9‐fold increased risk with hypoalbuminaemia [95% CI (1.03, 34.1); P = 0.046]. For Group 2, the increased risk was 23‐fold for failure of CVC removal [95% CI (7.48, 70.77); P < 0.001], 7.4‐fold for mechanical ventilation [95% CI (2.64, 21.08); P < 0.001], 4.4‐fold for hypoalbuminaemia [95% CI (1.56, 12.56); P = 0.005], 3.1‐fold for neutropaenia [95% CI (1.31, 7.69); P = 0.010] and 2.2‐fold for male gender [95% CI (1.02, 4.71); P = 0.043]. Therapeutic choices should be guided by sound knowledge of local epidemiological trends in candidaemia. Removal of CVC significantly reduces mortality and is an essential step in the management of candidaemia.
Medium chain fatty acid ethyl esters – activation of antimicrobial effects by Malassezia enzymes
Authors: Mayser Peter
Published: February 2015

Free medium and short chain fatty acids are known to have broad antimicrobial activity. However, their practical use in topical therapy is limited by their intensive smell and acidity. Surprisingly, a nearly identical antimicrobial effect was found with the ethyl ester derivatives of these fatty acids, but only against Malassezia (M.) yeast, not against Candida spp. Obviously, these esters are hydrolysed by M. enzymes, thus generating a selective activation of antimicrobial activity especially in areas well populated with these yeast (‘targeting’). Octanoic acid ethyl ester (CAS 106‐32‐1) was found to be most suitable. In an agar dilution test, the minimal inhibitory concentrations against M. globosa, M. pachydermatis and M. sympodialis, respectively, ranged between ~5 and 10 mmol l−1 after 10 days of incubation. The effect started immediately and was not delayed by other lipid sources applied simultaneously. Based on these data, fatty acid monoesters may represent a new therapeutic concept in M.‐associated diseases.
Peritoneal mast cell degranulation and gastrointestinal recovery in patients undergoing colorectal surgery
Authors: Berdún S. , Bombuy E. , Estrada O. , Mans E. , Rychter J. , Clavé P. , Vergara P.
Published: February 2015

Background

Degranulation of peritoneal mast cells (MCs) induced by intestinal manipulation has been proposed as a pathophysiological factor in postoperative ileus (POI). We aimed to explore the relationship between peritoneal and colonic MC degranulation and gastrointestinal (GI) recovery following colectomy.

Methods

Patients undergoing elective laparoscopic cholecystectomy (using a laparoscope and small abdominal incisions, n = 14), and elective laparoscopic (n = 32) or open partial colectomy (through a large abdominal incision, n = 10) were studied. MC protease tryptase and chymase were studied in peritoneal fluid at the beginning, middle, and end of each surgical intervention. Density of MCs in colectomy samples were examined and oro‐caecal transit time by breath test, GI function recovery by clinical composite endpoint GI‐2 and association between MC proteases and clinical recovery.

Key Results

Open and laparoscopic colectomy caused greater peritoneal release of tryptase and chymase (323.0 ng/mL [IQR: 53.05–381.4] and 118.6 ng/mL [IQR: 53.60–240.3]), than cholecystectomy (41.64 ng/mL [IQR: 11.17–90.93]) at the end of the surgical intervention. However, there were no differences between laparoscopic and open colectomy. Increased peritoneal protease release during surgery was observed in patients who developed POI after colectomy.

Conclusions & Inferences

Colorectal surgery causes protease release from peritoneal MCs. Protease release does not differ between both types of colectomy (laparoscopy vs laparotomy). However, MC activation is increased in colectomy patients developing POI. Therefore, degranulation of peritoneal MCs as a factor contributing to human POI after colectomy might be considered in future studies as a target to avoid POI.
Does spatial heterogeneity blur the signature of dispersal syndromes on spatial patterns of woody species? A test in a tropical dry forest
Authors: Jara‐Guerrero Andrea , De la Cruz Marcelino , Espinosa Carlos I. , Méndez Marcos , Escudero Adrián
Published: February 2015

Spatial patterns of adult plants are a consequence of several ecological processes related to seed dispersal and recruitment. Dispersal limitation, mediated by dispersal syndrome, is considered a key factor in the formation of adult plant spatial patterns. Although this initial pattern determined by dispersal has been thoroughly studied, the subsequently modification by the effect of additional ecological factors, such as habitat heterogeneity is less understood. We explored the relative importance of dispersal syndrome and spatial heterogeneity on the realization of spatial patterns of adult trees in an Ecuadorian tropical dry forest. The spatial distribution of 28 species was modeled with four different spatial point processes each: homogeneous Poisson (HPP), inhomogeneous Poisson (IPP), homogeneous Poisson cluster (HPCP), and inhomogeneous Poisson cluster process (IPCP). These models allowed us to discern between effects of random processes, habitat heterogeneity, limited dispersal, and joint effects of habitat heterogeneity and limited dispersal. We employed Akaike's information criterion (AIC) to select the model which best fit the spatial pattern of each species. The best model of each species was used to analyze differences in cluster size and degree of aggregation, between dispersal syndromes. Seventy‐five percent of the species showed inhomogeneous patterns. IPCP yielded the best fit for the spatial distribution of 50% of species in the studied forest and was the prevalent model for the three dispersal syndromes. Thus, the effect of spatial heterogeneity was prevalent in the distribution of most species in this dry tropical forest. Only 21% of species had spatial patterns compatible with random mechanisms associated to limited dispersal around parent sources. Clearly, ignoring habitat heterogeneity could bias the analysis of relationships between dispersal syndrome and species patterns.
Operculum regeneration following failed predation in the Silurian gastropod Oriostoma
Authors: Peel John S.
Published: February 2015

Regeneration of the calcareous rigiclaudent operculum following severe, non‐lethal, predatory attacks is described in two specimens of the characteristic Silurian gastropod Oriostoma from the English Midlands. This is the first record of the regeneration of opercula in Palaeozoic gastropods and of opercula conjoined with shells that have been repaired after significant, failed, durophagous attacks. In one specimen, a series of repaired injuries culminates in a repaired aperture closed by the operculum. In the second specimen, new shell growth has failed to recover the full extent of the original broken whorl, and the new aperture and operculum, though well developed, are smaller than the originals. Both opercula are unusually thin centrally when compared to other, strongly domed, Oriostoma opercula.
Controlling the blood glucose of type 1 diabetes mice by co‐culturing MIN‐6 β cells on 3D scaffold
Authors: Yuan Xiaoqi , Huang Yan , Guo Yibing , Wang Lei , Guo Qingsong , Xu Tianxing , Wu Di , Zhou Pengcheng , Zhu Shajun , Wang Yao , Fan Xiangjun , Zhu Mingyan , Lu Yuhua , Wang Zhiwei
Published: February 2015

T1D is an autoimmune disease, which may be caused by lack of insulin‐secreting β cells due to damage of autoimmune system. Living with T1D is a challenge for the child and the family; cell transplantation is a treatment option for diabetes in children. To establish a microenvironment suitable for cell growth and proliferation as well as for sustained cellular function, we used MIN‐6 β cells as seed cells and SF‐IV collagen as a 3D composite scaffold to construct artificial pancreas in this experiment. The cell viabilities were determined by MTT assay, and the response of cells to different glucose concentrations was observed by glucose stimulation test. Artificial pancreas was transplanted into the abdominal cavity of T1D mice, and the changes of blood glucose were monitored. After 10 days, insulin expression was detected by immunohistochemical method, and the claybank stained area showed effectiveness of insulin secretion. A series of experiments showed that implantation of 3D cell scaffold into the abdominal cavity can effectively control the blood glucose level of T1D mice. It also had longer‐lasting hypoglycemic effects than simple cell transplantation, which was expected to become a new method for the treatment of T1D.
Minute perivascular epithelioid cell (PEC) nests in the abdominal lymph nodes—a putative precursor of PEComa
Authors: Nagasaka Toru , Murakami Yoshiko , Sasaki Eiichi , Hosoda Waki , Nakanishi Toru , Yatabe Yasushi
Published: February 2015

A perivascular epithelioid cell tumor (PEComa) is a peculiar growth defined as a mesenchymal tumor composed of histologically and immunohistochemically distinct perivascular epithelioid cells (PECs). Because neither normal counterparts nor precursor lesions of PEComa have been identified, we examined minute PEC nests, ranged from 0.8 mm to 10 mm, to investigate the possible origin of the PEComa. We examined a total of 80 677 para‐aortic and pelvic lymph nodes that were systematically dissected from 1656 patients for gynecological malignancies. The identified lesions were confirmed immunohistochemically with multiple PEC markers, including smooth muscle actin, HMB45, melan‐A, MiTF, ER and PgR. A total of 66 minute PEC nests were found in 21 patients (1.3% of the total population) with an average frequency of 3.1 lesions per patient. In cases of multiple involvement, 11 of 13 nests were located at the same level of multiple lymph node or on continuous levels. The lesions were preferentially distributed at the level of para‐aortic and high pelvic lymph nodes. All nests were positive for actin and HMB45, whereas the other markers were positive with varying frequencies. The minute PEC nests may be associated with the possible normal counterpart of PEComas.
Fruit shading enhances peel color, carotenes accumulation and chromoplast differentiation in red grapefruit
Authors: Lado Joanna , Cronje Paul , Alquézar Berta , Page Anton , Manzi Matías , Gómez‐Cadenas Aurelio , Stead Anthony D. , Zacarías Lorenzo , Rodrigo María Jesús
Published: February 2015

The distinctive color of red grapefruits is due to lycopene, an unusual carotene in citrus. It has been observed that red ‘Star Ruby’ (SR) grapefruits grown inside the tree canopy develop a more intense red coloration than those exposed to higher light intensities. To investigate the effect of light on SR peel pigmentation, fruit were bagged or exposed to normal photoperiodic conditions, and changes in carotenoids, expression of carotenoid biosynthetic genes and plastid ultrastructure in the peel were analyzed. Light avoidance accelerated chlorophyll breakdown and induced carotenoid accumulation, rendering fruits with an intense coloration. Remarkably, lycopene levels in the peel of shaded fruits were 49‐fold higher than in light‐exposed fruit while concentrations of downstream metabolites were notably reduced, suggesting a bottleneck at the lycopene cyclization in the biosynthetic pathway. Paradoxically, this increment in carotenoids in covered fruit was not mirrored by changes in mRNA levels of carotenogenic genes, which were mostly up‐regulated by light. In addition, covered fruits experienced profound changes in chromoplast differentiation, and the relative expression of genes related to chromoplast development was enhanced. Ultrastructural analysis of plastids revealed an acceleration of chloroplasts to chromoplast transition in the peel of covered fruits concomitantly with development of lycopene crystals and plastoglobuli. In this sense, an accelerated differentiation of chromoplasts may provide biosynthetic capacity and a sink for carotenoids without involving major changes in transcript levels of carotenogenic genes. Light signals seem to regulate carotenoid accumulation at the molecular and structural level by influencing both biosynthetic capacity and sink strength.
Shifting Currents: Dwight Eisenhower and the Dynamic of Presidential Opportunity Structure
Authors: Polsky Andrew J.
Published: February 2015

The opportunity structure framework has become a cornerstone of presidency research over the past generation. Yet the way scholars have construed opportunity structure has been too narrow. Where they have stressed the partisan regime context in which a president is situated, other contextual elements often weigh more heavily on a president's calculation of what he can and cannot do. Further, the regime context is relatively static within any administration, but the opportunity structure a president faces will change rapidly. These choices are often the consequence of a president's earlier actions. His choices will set in motion new forces to which he will later have to respond. The presidency of Dwight Eisenhower serves to illustrate the value of a broadened and more dynamic conception of the opportunity structure approach.
Polls and Elections: Leviathan's Reach? The Impact of Political Consultants on the Outcomes of the 2012 Republican Presidential Primaries and Caucuses
Authors: Cain Sean A.
Published: February 2015

Recent scholarship into American political parties argues that the power to nominate presidential candidates has not entirely devolved from the party to voters but retains party influence via a network of allied actors including political consultants. Once party elites coalesce around a preferred candidate, primary voters tend to comply with their will. However, scholarship has not yet shown whether consultants help produce this effect. Consultants, even those with close contractual ties to the party organization, do not behave as this view expects, and they worked for several GOP candidates in 2012, enhancing intraparty competition rather than rallying around the front‐runner.
How Policy Rules Shape the Structure and Performance of Collaborative Governance Arrangements
Authors: Siddiki Saba N. , Carboni Julia L. , Koski Chris , Sadiq Abdul‐Akeem
Published: February 2015

Local food system governance increasingly occurs in collaborative venues at the local, state, and regional levels. Prominent examples of such are food policy councils (FPCs). FPCs take a systemic approach to improve local food systems by including diverse stakeholders to advise on policy development. The authors study public FPCs to understand how policies structure the stakeholder composition and goals of FPCs and how FPCs’ stakeholder composition facilitates and/or impedes performance. Data come from a content analysis of policies that mandate the structure and functions of public FPCs and interviews with FPC representatives. Findings indicate that FPCs connected to a broader array of food policy actors in their communities produce more diverse policy outputs, but this outcome is tempered by whether council members represent personal or organizational interests.
Highway to Economic Growth? Competition in Public Works Tenders in the Democratic Republic of Congo
Authors: Galletta Sergio , Jametti Mario , Redonda Agustin
Published: February 2015

The Democratic Republic of Congo (DRC) is one of the poorest countries in the world. The construction sector will play an essential part to bring the country on the path of economic growth, and competition within the sector is crucial to achieve this goal. In this paper, we analyse the effect of competition in public works tenders in the DRC, using a unique and newly assembled database on public works contracts. We find that the number of participating bidders significantly reduces contract prices, confirming our prior hypothesis that competitive pressure can enhance the overall performance of the sector. Further, we account for the possibility of heteregenous tender participants, finding that the competition effect can vary with the degree of bidders' heterogeneity.
Hostile Worlds or Connected Lives? Research on the Interplay Between Intimacy and Economy
Authors: Bandelj Nina , Morgan Paul James , Sowers Elizabeth
Published: February 2015

Economic sociologists have devoted most of their attention to the activities of individuals and firms in markets. However, recent attempts have pushed for a better understanding of the relationship between intimacy and economy. Such efforts have been inspired, in large part, by Viviana Zelizer (2000, 2005). In her inquiry on the purchase of intimacy, Zelizer proposed seminal differentiations between the “hostile worlds,” “nothing but,” and “connected lives” perspectives, and advanced a cultural relational analysis of the economy. In this essay, we review research that applies Zelizer's framework, and suggest substantive and analytical avenues for future research on economy/intimacy nexus.
Beliefs, Practical Knowledge, and Context: A Longitudinal Study of a Beginning Biology Teacher's 5E Unit
Authors: Sickel Aaron J. , Friedrichsen Patricia
Published: February 2015

The purpose of this three‐year case study was to understand how a beginning biology teacher (Alice) designed and taught a 5E unit on natural selection, how the unit changed when she took a position in a different school district, and why the changes occurred. We examined Alice's developing beliefs about science teaching and learning, practical knowledge, and perceptions of school context in relation to the 5E unit. Data sources consisted of interviews, classroom observations, and lesson materials. We found that Alice placed more emphasis on the explore phase, less emphasis on the engage and explain phases, and removed the elaborate phase over time. Alice's beliefs about science teaching and learning acted as a filter for making sense of practical knowledge and perceptions of context. Although her beliefs were student centered, they aligned with discovery learning in which little intervention from the teacher is required. We discuss how her beliefs, practical knowledge, and perceptions of context explained the changes in her practice. This study sheds insight into the nature of beliefs and how they relate to the 5E lesson phases, as well as the different lenses for viewing the 5E instructional model. Implications for science teacher preparation and induction programs are discussed.
An Emergent Framework: Views of Mathematical Processes
Authors: Sanchez Wendy B. , Lischka Alyson E. , Edenfield Kelly W. , Gammill Rebecca
Published: February 2015

The findings reported in this paper were generated from a case study of teacher leaders at a state‐level mathematics conference. Investigation focused on how participants viewed the mathematical processes of communication, connections, representations, problem solving, and reasoning and proof. Purposeful sampling was employed to select nine participants who were then interviewed and observed as they presented a session at the conference. Participants' statements revealed differences in their views of mathematical processes. The analysis led to an emergent framework for views of mathematical processes that includes three levels: participatory, experiential, and sense‐making. Implications are shared for mathematics methods instructors, professional learning, and research. Discussion also relates the framework to the Standards for Mathematical Practice.
Preservice Teachers of High School Mathematics: Success, Failure, and Persistence in the Face of Mathematical Challenges
Authors: Sinicrope Rose , Eppler Marion , Preston Ronald V. , Ironsmith Marsha
Published: February 2015

The goal of this study was to identify variables related to success and resilience in an undergraduate, high school mathematics teacher education program. Over a five‐year period, we tracked the academic performance and achievement motivation goals of multiple cohorts of students. Students who successfully completed their degrees had higher grade point average (GPAs) upon entering the program, earned higher grades in their first college mathematics course, and failed fewer courses than students who left the program or university. Learning and performance motivational goals did not predict success in the program. Performance goals decreased over time. Nearly half the successful students repeated one or more mathematics courses. Ten students completed their degrees, obtained a teaching license, and are teaching despite the need for multiple repetitions of the same mathematics courses. These persistent students did not differ from their peers in motivational goals. Our results suggest that although students with higher GPAs and initial mathematics grades were more likely to complete the program, students who experienced challenges in mathematics courses were able to succeed. We discuss the implications of these results for recruiting, advising, and retention of students in mathematics education programs.
Evaluation of lymph node aspirates at diagnosis and relapse in dogs with high‐grade multicentric lymphoma and comparison with survival time
Authors: Munasinghe Lilani I. , Kidney Beverly A. , MacDonald‐Dickinson Valerie , Larson Victoria S. , Jackson Marion L. , Fernandez Nicole J.
Published: February 2015

Background

Canine high‐grade multicentric lymphoma, a common disease with variable response to chemotherapy, is often diagnosed using cytology.

Objectives

The purpose of the study was to compare cytologic features of canine peripheral lymph node aspirates collected at diagnosis and at relapse, and evaluate their usefulness in predicting survival.

Methods

Cytologic scoring based on a rubric and nuclear morphometry analyses were performed on cytologic smears collected at diagnosis and at relapse. Scores at diagnosis and relapse were compared by pairedt‐test and evaluated in relation to time from diagnosis to remission, remission to relapse, relapse to death, and total survival time, using the Cox proportional‐hazards regression model.

Results

Number of mitoses and total cytologic score were significantly higher at relapse compared to diagnosis (P < .05). None of the nuclear morphometry measures were significantly different between diagnosis and relapse. The presence of binucleated or multinucleated cells at diagnosis was associated with a shorter remission and decreased total survival (P < .05). Increased mean nucleoli at relapse was associated with longer remission and total survival (P < .05). Increased minimum nuclear radius and diameter at diagnosis were associated with a decreased time from relapse to death (P < .05). Several nuclear morphometry measures at relapse were associated with a shorter time from diagnosis to remission (P < .05).

Conclusions

Number of mitoses and total score were higher at relapse than at diagnosis in canine lymphoma.The presence of binucleated or multinucleated cells at diagnosis may be useful as indicator of a poor prognosis. Further studies including a larger number of cases are required to reinforce the prognostic values of these cytologic features.
In vivoevaluation of the cornea and conjunctiva of the normal laboratory beagle using time‐ and Fourier‐domain optical coherence tomography and ultrasound pachymetry
Authors: Strom Ann R. , Cortés Dennis E. , Rasmussen Carol A. , Thomasy Sara M. , McIntyre Kim , Lee Shwu‐Fei , Kass Philip H. , Mannis Mark J. , Murphy Christopher J.
Published: February 2015

Objective

To obtain normative data for the canine cornea and conjunctiva using high‐resolution time‐ and Fourier‐domain optical coherence tomography (TD‐OCTandFD‐OCT) and ultrasound pachymetry (USP).

Animals

One hundred sixty‐eight eyes of 133 healthy young intact laboratory beagles.

Procedures

The cornea and conjunctiva of 16 eyes of 8 healthy young intact female beagles were imaged usingFD‐OCT. Corneal thickness was measured withFD‐OCTandUSP, while corneal epithelial thickness and conjunctival epithelial thickness were measured withFD‐OCT. The central corneal thickness (CCT) was determined in 152 eyes of 125 healthy young adult intact female (35) and male (90) beagles usingTD‐OCT. Mixed effects linear regression was used for statistical analysis.

Results

TheCCTwas (mean ± standard deviation) 497.54 ± 29.76, 555.49 ± 17.19, and 594.81 ± 33.02 μm as measured byFD‐OCT,USP, andTD‐OCT, respectively. The central, superior paraxial, superior perilimbal corneal epithelial thickness and superior bulbar conjunctival epithelial thickness were 52.38 ± 7.27, 56.96 ± 6.47, 69.06 ± 8.84 and 42.98 ± 6.17 μm, respectively. When comparing techniques used for measuringCCT(USPvs.FD‐OCTandFD‐OCTvs.TD‐OCT),USPandTD‐OCTgenerated significantly greater values in comparison withFD‐OCT(bothP < 0.001). For all dogs,CCTincreased with increasing age and body weight (bothP < 0.001) and was higher in intact males vs. females usingTD‐OCT(P = 0.034).

Conclusion

High‐resolutionFD‐OCTandTD‐OCTprovide detailed noninvasive evaluation ofin vivocanine anterior segment structures. Normative values of the canine cornea and conjunctiva are reported.
Long‐term cultured neonatal islet cell clusters demonstrate better outcomes for reversal of diabetes: in vivo and molecular profiles
Authors: Jimenez‐Vera Elvira , Davies Sussan , Phillips Peta , O'Connell Philip J. , Hawthorne Wayne J.
Published: February 2015

Background

Porcine neonatal islet‐like cell clusters (NICC) are being considered as a source of β‐cell replacement. However, the lag time to full function due to hormonal immaturity remains a problem. This study aimed to determine whether time in culture was important for NICC function in vivo.

Methods

Neonatal islet‐like cell clusters were isolated from piglets aged between 1 and 3 days, and cultured for up to 27 days post‐isolation. Each week, NICC number, viability, and function were determined.

Results

Neonatal islet‐like cell clusters cultured for 12, 19, and 27 days achieved normal blood glucose levels at 46 days (85% of animals), 32 days (100% of animals), and 35 days (81% of animals), respectively. By comparison, standard 6‐day culture took a mean of 63 days to achieve normoglycemia in 35% of animals. Longer time in culture resulted in a significant loss of islet equivalent over time. However, insulin gene expression levels were significantly higher at days 12, 19, 27 compared to day 6. Glucagon gene expression was highest at day 12, and significantly higher than day 6 at all time points. Bcl‐2 gene expression increased over time, and tissue factor (TF) gene expression was highest on day 6 and then decreased over the remaining time points.

Conclusion

Culture of NICC for 12 days provides the best balance in vivo functional outcome for transplantation, shown by better reversal of diabetes, and higher levels of gene expression for insulin, glucagon and Bcl‐2 and lower levels of TF expression with acceptable NICC number loss in terms of time and expense.
The Impact of Arbitrary Oriented Ellipsoidal Shell With a Barrier: Analytical Study
Authors: Mansoor-Baghaei Shahab , Sadegh Ali M.
Published: February 2015

In this paper, a closed form solution of an arbitrary oriented hollow elastic ellipsoidal shell impacting with an elastic flat barrier is presented. It is assumed that the shell is thin under the low speed impact. Due to the arbitrary orientation of the shell, while the pre-impact having a linear speed, the postimpact involves rotational and translational speed. Analytical solution for this problem is based on Hertzian theory (Johnson, W., 1972, Impact Strength of Materials, University of Manchester Institute of Science and Technology, Edward Arnold Publication, London) and the Vella’s analysis (Vella et al., 2012, “Indentation of Ellipsoidal and Cylindrical Elastic Shells,” Phys. Rev. Lett., 109, p. 144302) in conjunction with Newtonian method. Due to the nonlinearity and complexity of the impact equation, classical numerical solutions cannot be employed. Therefore, a linearization method is proposed and a closed form solution for this problem is accomplished. The closed form solution facilitates a parametric study of this type of problems. The closed form solution was validated by an explicit finite element method (FEM). Good agreement between the closed form solution and the FE results is observed. Based on the analytical method the maximum total deformation of the shell, the maximum transmitted force, the duration of the contact, and the rotation of the shell after the impact were determined. Finally, it was concluded that the closed form solutions were trustworthy and appropriate to investigate the impact of inclined elastic ellipsoidal shells with an elastic barrier.
Takagi–Sugeno Fuzzy Predictive Control for a Class of Nonlinear System With Constrains and Disturbances
Authors: Wang Bin , Zhang Jianwei , Zhu Delan , Chen Diyi
Published: February 2015

This paper investigates the fuzzy predictive control for a class of nonlinear system with constrains under the condition of noise. Based on the fuzzy linearization theory, a class of nonlinear systems can be described by the Takagi–Sugeno (T–S) fuzzy model. The T–S fuzzy model and predictive control are combined to stabilize the proposed class of nonlinear system, and the detailed mathematical derivation is given. Moreover, the designed controller has been optimized even if the system is constrained by output and control input, or perturbed by external disturbances. Finally, numerical simulations including three-dimensional Lorenz system, four-dimensional Chen system and five-dimensional nonlinear system with external disturbances are presented to demonstrate the universality and effectiveness of the proposed scheme. The approach proposed in this paper is simple and easy to implement and also provides reference for relevant nonlinear systems.
On a Numerical Approach to Solve Multi-Order Fractional Differential Equations With Initial/Boundary Conditions
Authors: Firoozjaee M. A. , Yousefi S. A. , Jafari H. , Baleanu D.
Published: February 2015

In this manuscript, a new method is introduced for solving multi-order fractional differential equations. By transforming the fractional differential equations into an optimization problem and using polynomial basis functions, we obtain the system of algebraic equation. Then, we solve the system of nonlinear algebraic equation and obtain the coefficients of polynomial expansion. Also, we show the convergence of the method. Some numerical examples are presented which illustrate the theoretical results and the performance of the method.
Dual Residual for Centralized Augmented Lagrangian Coordination Based on Optimality Conditions
Authors: Xu Meng , Fadel Georges , Wiecek Margaret M.
Published: February 2015

Centralized augmented Lagrangian coordination (ALC) has drawn much attention due to its parallel computation capability, efficiency, and flexibility. The initial setting and update strategy of the penalty weights in this method are critical to its performance. The traditional weight update strategy always increases the weights and research shows that inappropriate initial weights may cause optimization failure. Making use of the Karush–Kuhn–Tucker (KKT) optimality conditions for the all-in-one (AIO) and decomposed problems, the terms “primal residual” and “dual residual” are introduced into the centralized ALC, and a new update strategy considering both residuals and thus guaranteeing the unmet optimality condition in the traditional update is introduced. Numerical tests show a decrease in the iteration number and significant improvements in solution accuracy with both calculated and fine-tuned initial weights using the new update. Additionally, the proposed approach is capable to start from a wide range of possible weights and achieve optimality, and therefore brings robustness to the centralized ALC.
Design of a Novel Statically Balanced Mechanism for Laparoscope Holders With Decoupled Positioning and Orientating Manipulation
Authors: Kuo Chin-Hsing , Lai Shao-Jung
Published: February 2015

This paper presents a novel mechanism concept of laparoscope holders used for minimally invasive surgery (MIS). The mechanism is made of a parallelogram linkage and a parallel mechanism, which, respectively, serve as a robotic positioning arm and an orientating wrist of the holder. Due to its special geometry, the mechanism possesses several interesting kinematic properties. First, the laparoscope, which is held by the end-effector, can illustrate a remote center-of-motion (RCM) kinematics at the surgical incision point. Second, the position of the RCM point is solely defined by the parallelogram, whereas the orientation and insertion length of the laparoscope are governed by the parallel mechanism. Such an arrangement suggests a decoupled positioning and orientating manipulation for the holder, which is clinically helpful in laparoscopic MIS. Third, the overall mechanism including the parallelogram linkage and the parallel mechanism can be statically balanced at any configuration within the workspaces by using common linear springs. In other words, no electrical actuation or mechanical locks are required for making the laparoscope rest at any position and orientation. The design procedure for static balancing is detailed in the paper, and the theoretical formulation of the statically balanced mechanism is verified by a numerical example and computer simulation. The computer-aided design (CAD) model of the holder is constructed for evaluating its workspace and a physical prototype using commercial springs is built up and tested. It shows that the prototype that uses nonideal (commercial) springs can be statically balanced within the overall workspace, since the shortage/overshoot of the potential energy in the positioning mechanism and orientating mechanism, which are theoretically 6.8% and 5.1% of their total potential energies in maximum, are fully compensated by the friction effect.
Prediction of Burst Pressure of Pipes With Geometric Eccentricity
Authors: Chen Zhanfeng , Zhu Weiping , Di Qinfeng , Wang Wenchang
Published: February 2015

An analytical model was proposed in this paper to predict the burst pressure of a pipe with geometric eccentricity. With application of the complex elastic potential function method in a bipolar coordinate system, the authors first derived an analytical solution of stresses in an eccentric pipe and then obtained the formula of predicting burst pressure by combining the solution with the Tresca criterion. Finally, the effect of eccentricity and the ratio of thickness to diameter of pipe on burst pressure were discussed. Our results show that a slight eccentricity can significantly decrease the burst pressure. In the special case of zero-eccentricity for a concentric pipe, our model yields results that are consistent with experiments data published by others and theoretical results predicted by models proposed by other researchers without considering the effect of eccentricity. In the case of eccentricity for an eccentric pipe, the calculating results of our model are also consistent with that of finite element model (FEM). The theoretical model and results presented in this paper have a broader application in predicting the burst pressure for pipes commonly used in oil and gas industry.
An Improved One-Dimensional Model for Liquid Slugs Traveling in Pipelines
Authors: Tijsseling Arris S. , Hou Qingzhi , Bozkuş Zafer
Published: February 2015

An improved one-dimensional (1D) model—compared to previous work by the authors—is proposed, which is able to predict the acceleration and shortening of a single liquid slug propagating in a straight pipe with a downstream bend. The model includes holdup at the slug's tail and flow separation at the bend. The obtained analytical and numerical results are validated against experimental data. The effects of holdup, driving pressure and slug length are examined in a parameter variation study.
Effect of Specimen Geometry on the Predicted Mechanical Behavior of Polyethylene Pipe Material1
Authors: EL-Bagory Tarek M. A. A. , Alkanhal Tawfeeq A. R. , Younan Maher Y. A.
Published: February 2015

The primary objective of the present paper is to depict the mechanical behavior of high density polyethylene (HDPE) pipes under different loading conditions with different specimen geometries to provide the designer with reliable design data relevant to practical applications. Therefore, it is necessary to study the effect of strain rate, ring configuration, and grip or fixture type on the mechanical behavior of dumb-bell-shaped (DBS), and ring specimens made from HDPE pipe material. DBS and ring specimens are cut from the pipe in longitudinal and circumferential (transverse) directions, respectively. On the other hand, the ring specimen configuration is classified into two types; full ring (FR), and notched ring (NR) (equal double notch from two sides of NR specimen) specimens according to ASTM D 2290-12 standard. Tensile tests are conducted on specimens cut out from the pipe with thickness of 10 mm at different crosshead speeds (10–1000 mm/min), and ambient temperature, Ta = 20 °C to investigate the mechanical properties of DBS and ring specimens. In the case of test specimens taken from the longitudinal direction from the pipe, a necking phenomenon before failure appears at different locations along the gauge section. On the other hand, the fracture of NR specimens occurs at one notched side. The results demonstrated that the NR specimen has higher yield stress than DBS and FR specimens at all crosshead speeds. The present experimental work reveals that the crosshead speed has a significant effect on the mechanical behavior of both DBS and ring specimens. The fixture type plays an important role in the mechanical behavior for both FR and NR specimens at all crosshead speeds.
Deposition of highly textured AlN thin films by reactive high power impulse magnetron sputtering
Authors: Moreira Milena A. , Törndahl Tobias , Katardjiev Ilia , Kubart Tomas
Published: February 2015

Aluminum nitride thin films were deposited by reactive high power impulse magnetron sputtering (HiPIMS) and pulsed direct-current on Si (100) and textured Mo substrates, where the same deposition conditions were used for both techniques. The films were characterized by x-ray diffraction and atomic force microscopy. The results show a pronounced improvement in the AlN crystalline texture for all films deposited by HiPIMS on Si. Already at room temperature, the HiPIMS films exhibited a strong preferred (002) orientation and at 400 °C, no contributions from other orientations were detected. Despite the low film thickness of only 200 nm, an ω-scan full width at half maximum value of 5.1° was achieved on Si. The results are attributed to the high ionization of sputtered material achieved in HiPIMS. On textured Mo, there was no significant difference between the deposition techniques.
The Measurement and Interpretation of Dietary Protein Distribution During a Rugby Preseason
Authors: MacKenzie Kristen , Slater Gary , King Neil , Byrne Nuala
Published: February 2015

Evidence suggests that increasing protein distribution may be desirable to promote muscle protein synthesis (MPS) in combination with resistance exercise. However, there is a threshold above which additional protein consumption has limited benefit for MPS and may promote protein loss due to increased oxidation. This study aimed to measure daily protein intake and protein distribution in a cohort of rugby players. Twenty-five developing elite rugby union athletes (20.5 ± 2.3 years, 100.2 ± 13.3 kg, 184.4 ± 7.4 cm) were assessed at the start and end of a rugby preseason. Using a 7-day food diary the reported daily protein intake was 2.2 ± 0.7 g·kg·day-1 which exceeds daily recommendations. The reported carbohydrate intake was 3.6 ± 1.3 g·kg·day-1 which may reflect a suboptimal intake or dietary underreporting. In general, the rugby athletes were regularly consuming more than 20 g of protein; 3.8 ± 0.9 times per day (68 ± 18% of eating occasions). In addition to documenting current dietary intakes, an excess protein estimation score was calculated to determine how frequently the rugby athletes consumed protein above a known effective dose with a margin of error. 2.0 ± 0.9 eating occasions contained protein in excess of doses (20 g) known to promote MPS. Therefore, it is currently unclear whether the consumption of regular large doses of protein will benefit rugby athletes via increasing protein distribution, or whether high protein intakes may have unintended effects including a reduction in carbohydrate and/or energy intake.