bluuebunny/crossref_metadata_2025 huggingface dataset:
Mask-Less Pocket Milling of Composites by Abrasive Waterjets: An Experimental Investigation
Authors: Srinivasu D. S. , Axinte D. A.
Published: March 2014

Milling pockets in advanced engineering composite materials (AECMs) by conventional methods is difficult due to machinability issues, such as heterogeneous constituents, softening of heat sensitive resin matrix, delamination, fiber pull-out, carcinogenic gases, and dust. On the other hand, waterjet (WJ) machining, among the unconventional approaches, is well known for machining a wide range of AECMs due to its unique features, exertion of low cutting force, low heat generation, no dangerous fume development and low airborne dust. However, from the preliminary studies, it was found that the conventional pocket milling tool path strategies existing in standard computer aided design (CAD) packages cannot be employed directly in milling AECMs with the WJs due to various reasons, such as less strength of composite materials in the transverse direction to the fiber orientation, and aggressive nature of high energy WJs. To address these issues, a novel jet path strategy for mask-less milling of pockets was proposed. This approach takes into account the nature of the highly aggressive fluidjets, the physical structure of the AECMs, and the limitations of the existing hardware controllers, which are not specifically designed for jet machining, while manoeuvring the jet over the surface to avoid undesired excessive erosion and contributes to the elimination of sacrificial masks. The proposed strategy is demonstrated by pocket milling of difficult to machine AECMs (glass and carbon fiber) by the WJ and abrasive waterjets (AWJ) along with geometric analysis on the pockets. The influence of various process parameters, such as water pressure, jet traverse rate, standoff distance (SOD), number of passes, on the milled surfaces was studied. Furthermore, the damage at various regions of the pocket was analyzed by scanning electron microscopy, to find out the causes of surface damages and re-cast of resin layer to address the damage was suggested. The effect of consideration of composite material's physical structure while milling was successfully demonstrated by generating pockets with minimum damage to the reinforcing fibers and delamination. A selection procedure between AWJs and WJs was proposed depending on the scaling of the targeted milling depth and precision required. Finally, modifications to the machine tool hardware controllers are suggested for efficient milling of AECMs.
Statistical model based iterative reconstruction (MBIR) in clinical CT systems: Experimental assessment of noise performance
Authors: Li Ke , Tang Jie , Chen Guang‐Hong
Published: March 2014

Purpose:

To reduce radiation dose in CT imaging, the statistical model based iterative reconstruction (MBIR) method has been introduced for clinical use. Based on the principle of MBIR and its nonlinear nature, the noise performance of MBIR is expected to be different from that of the well‐understood filtered backprojection (FBP) reconstruction method. The purpose of this work is to experimentally assess the unique noise characteristics of MBIR using a state‐of‐the‐art clinical CT system.

Methods:

Three physical phantoms, including a water cylinder and two pediatric head phantoms, were scanned in axial scanning mode using a 64‐slice CT scanner (Discovery CT750 HD, GE Healthcare, Waukesha, WI) at seven different mAs levels (5, 12.5, 25, 50, 100, 200, 300). At each mAs level, each phantom was repeatedly scanned 50 times to generate an image ensemble for noise analysis. Both the FBP method with a standard kernel and the MBIR method (Veo®, GE Healthcare, Waukesha, WI) were used for CT image reconstruction. Three‐dimensional (3D) noise power spectrum (NPS), two‐dimensional (2D) NPS, and zero‐dimensional NPS (noise variance) were assessed both globally and locally. Noise magnitude, noise spatial correlation, noise spatial uniformity and their dose dependence were examined for the two reconstruction methods.

Results:

(1) At each dose level and at each frequency, the magnitude of the NPS of MBIR was smaller than that of FBP. (2) While the shape of the NPS of FBP was dose‐independent, the shape of the NPS of MBIR was strongly dose‐dependent; lower dose lead to a “redder” NPS with a lower mean frequency value. (3) The noise standard deviation (σ) of MBIR and dose were found to be related through a power law of σ ∝ (dose)−β with the component β ≈ 0.25, which violated the classical σ ∝ (dose)−0.5 power law in FBP. (4) With MBIR, noise reduction was most prominent for thin image slices. (5) MBIR lead to better noise spatial uniformity when compared with FBP. (6) A composite image generated from two MBIR images acquired at two different dose levels (D1 and D2) demonstrated lower noise than that of an image acquired at a dose level of D1+D2.

Conclusions:

The noise characteristics of the MBIR method are significantly different from those of the FBP method. The well known tradeoff relationship between CT image noise and radiation dose has been modified by MBIR to establish a more gradual dependence of noise on dose. Additionally, some other CT noise properties that had been well understood based on the linear system theory have also been altered by MBIR. Clinical CT scan protocols that had been optimized based on the classical CT noise properties need to be carefully re‐evaluated for systems equipped with MBIR in order to maximize the methodˈs potential clinical benefits in dose reduction and/or in CT image quality improvement.
A Bacterial Tyrosine Phosphatase Inhibits Plant Pattern Recognition Receptor Activation
Authors: Macho Alberto P. , Schwessinger Benjamin , Ntoukakis Vardis , Brutus Alexandre , Segonzac Cécile , Roy Sonali , Kadota Yasuhiro , Oh Man-Ho , Sklenar Jan , Derbyshire Paul , Lozano-Durán Rosa , Malinovsky Frederikke Gro , Monaghan Jacqueline , Menke Frank L. , Huber Steven C. , He Sheng Yang , Zipfel Cyril
Published: March 2014

Move and Countermove

Receptors on plant cell surfaces are tuned to recognize molecular patterns associated with pathogenic bacteria.

Macho
et al.

(p.
1509
; published online 13 March) found that activation of one of these receptors in
Arabidopsis
results in phosphorylation of a specific tyrosine residue, which in turn triggers the plant's immune response to the phytopathogen
Pseudomonas syringae. P. syringae
counters by secreting a specifically targeted phosphatase, thus stalling the plant's immune response.
Polyhedra Self-Assembled from DNA Tripods and Characterized with 3D DNA-PAINT
Authors: Iinuma Ryosuke , Ke Yonggang , Jungmann Ralf , Schlichthaerle Thomas , Woehrstein Johannes B. , Yin Peng
Published: March 2014

Engineering Larger DNA Structures

Several approaches now exist for the self-assembly of DNA into nanostructures. For example, three-arm DNA tripods can be assembled into larger wireframe polyhedra, but for the most complicated shapes, assembly yields can be low, apparently because the flexibility of smaller tripods allows for misassembly.

Iinuma
et al.

(p.
65
, published online 13 March) now show that larger, stiffer tripods that have controlled arm lengths and interarm angles can be designed to form a wide variety of open wireframe polyhedra—including tetrahedra, cubes, and hexagonal prisms, with edges 100 nanometers in length.
Chicken biliary exosomes enhance CD4+T proliferation and inhibit ALV-J replication in liver
Authors: Wang Yue , Wang Guihua , Wang Zhenzhen , Zhang Huangge , Zhang Li , Cheng Ziqiang
Published: March 2014

Exosomes, which are small membrane vesicles of endocytic origin, carry lipids, RNA/miRNAs, and proteins and have immune modulatory functions. In this study, we isolated exosomes from the bile of specific pathogen-free chickens, 42–43 days of age, by using an ultracentrifugation and filtration method. The density of the exosomes, isolated by sucrose gradient fractionation, was between 1.13 and 1.19 g/mL. Electron microscopic observation of the liver showed that exosomes were present in the space of Disse and bile canaliculus. Chicken biliary exosomes displayed typical saucer-shaped, rounded morphology. Using liquid chromatography mass spectrum methodology, 196 proteins, including exosomal markers and several unique proteins, were identified and compared with mouse biliary exosomes. Noteworthy, CCCH type zinc finger antiviral protein was found on chicken biliary exosomes never described before. Furthermore, our data show that chicken biliary exosomes promote the proliferation of CD4+ and CD8+ T cells and monocytes from liver. In addition, chicken biliary exosomes significantly inhibit avian leukosis virus subgroup J, which is an oncogenic retrovirus, from replicating in the DF-1 cell line. These data indicate that chicken biliary exosomes possess the capacity to influence the immune responses of lymphocytes and inhibit avian leukosis virus subgroup J (ALV-J).
Foraging diversity in lactating New Zealand sea lions: insights from qualitative and quantitative fatty acid analysis
Authors: Meynier Laureline , Morel Patrick C.H. , Chilvers B. Louise , Mackenzie Duncan D.S. , Duignan Pádraig J.
Published: March 2014

Lactating New Zealand (NZ) sea lions (Phocarctos hookeri) exhibit different foraging patterns during their foraging trips, with benthic divers spending more energy at sea than mesopelagic conspecifics. We compared blubber fatty acids (FAs) of 14 benthic and 12 mesopelagic females captured at the Auckland Islands, NZ subantarctic, in late January 2000 using an analysis of similarities (ANOSIM). FA profiles between foraging types were significantly different (global R = 0.30, p = 0.001), suggesting a different use in prey resources. We then compared the diet predictions by quantitative FA signature analysis (QFASA) by using a prey FA library available in the region. Overall, diet predictions were significantly distinct between benthic and mesopelagic females (global R = 0.17, p = 0.022), although the diets consisted of the same prey but in different contributions. The results suggest benthic females do not compensate their higher foraging costs by feeding on prey with higher energy densities. Foraging areas of benthic females are not exploited by the trawling fishery; therefore, the benthic tactic might be a trade-off between a higher foraging cost and less resource competition.
Activation of pattern recognition receptors in brown adipocytes induces inflammation and suppresses uncoupling protein 1 expression and mitochondrial respiration
Authors: Bae Jiyoung , Ricciardi Carolyn J. , Esposito Debora , Komarnytsky Slavko , Hu Pan , Curry Benjamin J. , Brown Patricia L. , Gao Zhanguo , Biggerstaff John P. , Chen Jiangang , Zhao Ling
Published: March 2014

Pattern recognition receptors (PRR), Toll-like receptors (TLR), and nucleotide-oligomerization domain-containing proteins (NOD) play critical roles in mediating inflammation and modulating functions in white adipocytes in obesity. However, the role of PRR activation in brown adipocytes, which are recently found to be present in adult humans, has not been studied. Here we report that mRNA of TLR4, TLR2, NOD1, and NOD2 is upregulated, paralleled with upregulated mRNA of inflammatory cytokines and chemokines in the brown adipose tissue (BAT) of the obese mice. During brown adipocyte differentiation, mRNA and protein expression of NOD1 and TLR4, but not TLR2 and NOD2, is also increased. Activation of TLR4, TLR2, or NOD1 in brown adipocytes induces activation of NF-κB and MAPK signaling pathways, leading to inflammatory cytokine/chemokine mRNA expression and/or protein secretion. Moreover, activation of TLR4, TLR2, or NOD1 attenuates both basal and isoproterenol-induced uncoupling protein 1 (UCP-1) expression without affecting mitochondrial biogenesis and lipid accumulation in brown adipocytes. Cellular bioenergetics measurements confirm that attenuation of UCP-1 expression by PRR activation is accompanied by suppression of both basal and isoproterenol-stimulated oxygen consumption rates and isoproterenol-induced uncoupled respiration from proton leak; however, maximal respiration and ATP-coupled respiration are not changed. Further, the attenuation of UCP-1 by PRR activation appears to be mediated through downregulation of the UCP-1 promoter activities. Taken together, our results demonstrate the role of selected PRR activation in inducing inflammation and downregulation of UCP-1 expression and mitochondrial respiration in brown adipocytes. Our results uncover novel targets in BAT for obesity treatment and prevention.
CHD7 Expression Predicts Survival Outcomes in Patients with Resected Pancreatic Cancer
Authors: Colbert Lauren E. , Petrova Aleksandra V. , Fisher Sarah B. , Pantazides Brooke G. , Madden Matthew Z. , Hardy Claire W. , Warren Matthew D. , Pan Yunfeng , Nagaraju Ganji P. , Liu Elaine A. , Saka Burcu , Hall William A. , Shelton Joseph W. , Gandhi Khanjan , Pauly Rini , Kowalski Jeanne , Kooby David A. , El-Rayes Bassel F. , Staley Charles A. , Adsay N. Volkan , Curran Walter J. , Landry Jerome C. , Maithel Shishir K. , Yu David S.
Published: March 2014

Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease with poor outcomes with current therapies. Gemcitabine is the primary adjuvant drug used clinically, but its effectiveness is limited. In this study, our objective was to use a rationale-driven approach to identify novel biomarkers for outcome in patients with early-stage resected PDAC treated with adjuvant gemcitabine. Using a synthetic lethal screen in human PDAC cells, we identified 93 genes, including 55 genes linked to DNA damage responses (DDR), that demonstrated gemcitabine sensitization when silenced, including CHD7, which functions in chromatin remodeling. CHD7 depletion sensitized PDAC cells to gemcitabine and delayed their growth in tumor xenografts. Moreover, CHD7 silencing impaired ATR-dependent phosphorylation of CHK1 and increased DNA damage induced by gemcitabine. CHD7 was dysregulated, ranking above the 90th percentile in differential expression in a panel of PDAC clinical specimens, highlighting its potential as a biomarker. Immunohistochemical analysis of specimens from 59 patients with resected PDAC receiving adjuvant gemcitabine revealed that low CHD7 expression was associated with increased recurrence-free survival (RFS) and overall survival (OS), in univariate and multivariate analyses. Notably, CHD7 expression was not associated with RFS or OS for patients not receiving gemcitabine. Thus, low CHD7 expression was correlated selectively with gemcitabine sensitivity in this patient population. These results supported our rationale-driven strategy to exploit dysregulated DDR pathways in PDAC to identify genetic determinants of gemcitabine sensitivity, identifying CHD7 as a novel biomarker candidate to evaluate further for individualizing PDAC treatment. Cancer Res; 74(10); 2677–87. ©2014 AACR.
Evidence of Clinical Utility: An Unmet Need in Molecular Diagnostics for Patients with Cancer
Authors: Parkinson David R. , McCormack Robert T. , Keating Susan M. , Gutman Steven I. , Hamilton Stanley R. , Mansfield Elizabeth A. , Piper Margaret A. , DeVerka Patricia , Frueh Felix W. , Jessup J. Milburn , McShane Lisa M. , Tunis Sean R. , Sigman Caroline C. , Kelloff Gary J.
Published: March 2014

This article defines and describes best practices for the academic and business community to generate evidence of clinical utility for cancer molecular diagnostic assays. Beyond analytical and clinical validation, successful demonstration of clinical utility involves developing sufficient evidence to demonstrate that a diagnostic test results in an improvement in patient outcomes. This discussion is complementary to theoretical frameworks described in previously published guidance and literature reports by the U.S. Food and Drug Administration, Centers for Disease Control and Prevention, Institute of Medicine, and Center for Medical Technology Policy, among others. These reports are comprehensive and specifically clarify appropriate clinical use, adoption, and payer reimbursement for assay manufacturers, as well as Clinical Laboratory Improvement Amendments–certified laboratories, including those that develop assays (laboratory developed tests). Practical criteria and steps for establishing clinical utility are crucial to subsequent decisions for reimbursement without which high-performing molecular diagnostics will have limited availability to patients with cancer and fail to translate scientific advances into high-quality and cost-effective cancer care.

See all articles in this CCR Focus section, “The Precision Medicine Conundrum: Approaches to Companion Diagnostic Co-development.”

Clin Cancer Res; 20(6); 1428–44. ©2014 AACR.
Autonomous Adenomas Caused by Somatic Mutations of the Thyroid-Stimulating Hormone Receptor in Children
Authors: Grob Francisca , Deladoëy Johnny , Legault Laurent , Spigelblatt Linda , Fournier Anne , Vassart Gilbert , Van Vliet Guy
Published: March 2014

In adults, autonomous adenomas of the thyroid causing hyperthyroidism are relatively common and are most often due to somatic mutations that increase the constitutive activity of the thyroid-stimulating hormone receptor (TSHR). By contrast, autonomous adenomas in hyperthyroid children are exceptional and reports of their clinical and molecular characteristics are few. We reviewed papers describing 16 autonomous adenomas due to a somatic mutation activating the TSHR and diagnosed in patients younger than 18 years, to which we added two of our own unpublished observations in a 4- and 8-year-old with the same TSHR mutation (c.CAG>CAC; p.Asp633His). This revealed that (a) autonomous adenomas occur more often in the right lobe (11 of 14 with available information) and the associated hyperthyroidism tends to be more severe, possibly reflecting the richer vascular supply of the right thyroid lobe, and (b) mutations found in benign adenomas in children have been associated with cancer in adults, suggesting that malignancy requires a second ‘hit' at a later age.
NSF Workshop Report: Discovering General Principles of Nervous System Organization by Comparing Brain Maps across Species
Authors: Striedter Georg F. , Belgard T. Grant , Chen Chun-Chun , Davis Fred P. , Finlay Barbara L. , Güntürkün Onur , Hale Melina E. , Harris Julie A. , Hecht Erin E. , Hof Patrick R. , Hofmann Hans A. , Holland Linda Z. , Iwaniuk Andrew N. , Jarvis Erich D. , Karten Harvey J. , Katz Paul S. , Kristan William B. , Macagno Eduardo R. , Mitra Partha P. , Moroz Leonid L. , Preuss Todd M. , Ragsdale Clifton W. , Sherwood Chet C. , Stevens Charles F. , Stüttgen Maik C. , Tsumoto Tadaharu , Wilczynski Walter
Published: March 2014

Efforts to understand nervous system structure and function have received new impetus from the federal Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative. Comparative analyses can contribute to this effort by leading to the discovery of general principles of neural circuit design, information processing, and gene-structure-function relationships that are not apparent from studies on single species. We here propose to extend the comparative approach to nervous system ‘maps' comprising molecular, anatomical, and physiological data. This research will identify which neural features are likely to generalize across species, and which are unlikely to be broadly conserved. It will also suggest causal relationships between genes, development, adult anatomy, physiology, and, ultimately, behavior. These causal hypotheses can then be tested experimentally. Finally, insights from comparative research can inspire and guide technological development. To promote this research agenda, we recommend that teams of investigators coalesce around specific research questions and select a set of ‘reference species' to anchor their comparative analyses. These reference species should be chosen not just for practical advantages, but also with regard for their phylogenetic position, behavioral repertoire, well-annotated genome, or other strategic reasons. We envision that the nervous systems of these reference species will be mapped in more detail than those of other species. The collected data may range from the molecular to the behavioral, depending on the research question. To integrate across levels of analysis and across species, standards for data collection, annotation, archiving, and distribution must be developed and respected. To that end, it will help to form networks or consortia of researchers and centers for science, technology, and education that focus on organized data collection, distribution, and training. These activities could be supported, at least in part, through existing mechanisms at NSF, NIH, and other agencies. It will also be important to develop new integrated software and database systems for cross-species data analyses. Multidisciplinary efforts to develop such analytical tools should be supported financially. Finally, training opportunities should be created to stimulate multidisciplinary, integrative research into brain structure, function, and evolution.
High-Sensitivity C-Reactive Protein and Interleukin-6–Dominant Inflammation and Ischemic Stroke Risk
Authors: Luna Jorge M. , Moon Yeseon P. , Liu Khin M. , Spitalnik Steven , Paik Myunghee C. , Cheung Keun , Sacco Ralph L. , Elkind Mitchell S.V.
Published: March 2014

Background and Purpose—

Interleukin-6 (IL-6) is a proinflammatory cytokine with known autoregulatory feedback mechanisms. We hypothesized that elevated high-sensitivity C-reactive protein (hsCRP) relative to IL-6 confers an increased risk of ischemic stroke (IS), and low hsCRP relative to IL-6 a decreased risk, for individuals in the prospective, multiethnic, population-based Northern Manhattan Study (NOMAS).

Methods—

Serum hsCRP and IL-6 were measured in NOMAS participants at baseline. We created a trichotomized predictor based on the dominant biomarker in terms of quartiles: hsCRP-dominant, IL-6–dominant, and codominant groups. Cox proportional hazards models were used to calculate hazard ratios and 95% confidence intervals for the association between inflammatory biomarker group status and risk of incident IS.

Results—

Of 3298 participants, both hsCRP and IL-6 were available in 1656 participants (mean follow-up, 7.8 years; 113 incident IS). The hsCRP-dominant group had increased risk of IS (adjusted hazard ratio, 2.62; 95% confidence interval, 1.56–4.41) and the IL-6–dominant group had decreased risk (adjusted hazard ratio, 0.38; 95% confidence interval, 0.18–0.82) when compared with the referent group, after adjusting for potential confounders. Model fit was improved using the inflammation-dominant construct, over either biomarker alone.

Conclusions—

In this multiethnic cohort, when hsCRP-quartile was higher than IL-6 quartile, IS risk was increased, and conversely when IL-6 quartiles were elevated relative to hsCRP, IS risk was decreased. Construct validity requires confirmation in other cohorts.
Virtual Peer Effects in Social Learning Theory
Authors: Miller Brooke , Morris Robert G.
Published: March 2014

The current study examines the differential influence of face-to-face and virtual peers in predicting digital and traditional offending among college students through the lens of social learning theory (SLT). SLT components are explored to discern whether the theory holds for virtual peers, as it has for face-to-face peers using a structural equation modeling framework, thus making a substantial contribution to the social learning literature. Findings provide some support for SLT for both virtual only peers and the face-to-face peers model in relation to digital as well as traditional offending. In addition, findings suggest that virtual peer associations may be as important as traditional peer associations in explaining certain types of deviant behavior.
High-strain rate compressive behavior of multi-walled carbon nanotube dispersed thermoset epoxy resin
Authors: Naik Niranjan K , Pandya Kedar S , Kavala Venkateswara R , Zhang Wei , Koratkar Nikhil A
Published: March 2014

Compressive high-strain rate behavior of thermoset epoxy resin dispersed with multi-walled carbon nanotubes is presented. The present study investigates the effect of strain rate as well as effect of multi-walled carbon nanotube dispersion on the compressive stress–compressive strain behavior of thermoset epoxy resin. The amount of multi-walled carbon nanotubes dispersion was varied up to 3% by weight. The studies were carried out on compressive split Hopkinson pressure bar apparatus in the strain rate range of 800–3700/s. Processing of multi-walled carbon nanotubes-dispersed thermoset epoxy resin, testing, damage, and energy absorbing mechanisms and key findings are reported. It is observed that the compressive strength of thermoset epoxy resin increases up to 147% at high-strain rate compared with that at quasi-static loading. The corresponding increase for multi-walled carbon nanotubes-dispersed thermoset epoxy resin is up to 140%. It is also observed that the compressive strength and energy-absorption capability of thermoset epoxy resin increase with the addition of multi-walled carbon nanotubes.
Improving Foot Examinations in Patients With Diabetes
Authors: Szpunar Susan M. , Minnick Steven E. , Dako Imhoitsemeh , Saravolatz Louis D.
Published: March 2014

Purpose

The purpose of this project was to determine if a Performance-Improvement Continuing Medical Education (PI-CME) project, using the American Medical Association’s methodology, would help improve the timeliness and comprehensiveness of foot examinations in patients with diabetes.

Methods

A PI-CME project was conducted with the Internal Medicine faculty staff physicians (n = 8) and residents (n = 45). Following the 3 steps of PI-CME, participants received baseline reports about their performance defined by the American Diabetes Association’s guidelines for foot examinations (stage A). Each group received an educational intervention (stage B) and a reminder tool for use in the practice. Participants received individualized reports about their performance post intervention (stage C) for comparison with preintervention data and reflection on any changes in compliance.

Results

In the faculty and resident clinics, the percentage of patients who received an annual foot examination when due increased significantly. Both clinics also showed improvements in the percentage of patients who received all 3 components of the exam, with the greatest improvement in the resident clinic.

Conclusions

The PI-CME approach can be successfully used both with faculty staff physicians (who receive CME credits) and residents (who do not receive credits) to improve performance on diabetes quality measures.
Where Do Self-Concordant Goals Come From? The Role of Domain-Specific Psychological Need Satisfaction
Authors: Milyavskaya Marina , Nadolny Daniel , Koestner Richard
Published: March 2014

Previous research has shown that self-concordant goals are more likely to be attained. But what leads someone to adopt a self-concordant goal in the first place? The present research addresses this question by looking at the domains in which goals are set, focusing on the amount of psychological need satisfaction experienced in these domains. Across three experimental studies, we demonstrate that domain-related need satisfaction predicts the extent to which people adopt self-concordant goals in a given domain, laying the foundation for successful goal pursuit. In addition, we show that need satisfaction influences goal self-concordance because in need-satisfying domains people are both more likely to choose the most self-concordant goal (among a set of comparable choices), and are more likely to internalize the possible goals. The implications of this research for goal setting and pursuit as well as for the importance of examining goals within their broader motivational framework are discussed.
Artifact Reduction of Ultrasound Nakagami Imaging by Combining Multifocus Image Reconstruction and the Noise-Assisted Correlation Algorithm
Authors: Tsui Po-Hsiang , Tsai Yu-Wei
Published: March 2014

Several studies have investigated Nakagami imaging to complement the B-scan in tissue characterization. The noise-induced artifact and the parameter ambiguity effect can affect performance of Nakagami imaging in the detection of variations in scatterer concentration. This study combined multifocus image reconstruction and the noise-assisted correlation algorithm (NCA) into the algorithm of Nakagami imaging to suppress the artifacts. A single-element imaging system equipped with a 5 MHz transducer was used to perform the brightness/depth (B/D) scanning of agar phantoms with scatterer concentrations ranging from 2 to 32 scatterers/mm3. Experiments were also carried out on a mass with some strong point reflectors in a breast phantom using a commercial scanner with a 7.5 MHz linear array transducer operated at multifocus mode. The multifocus radiofrequency (RF) signals after the NCA process were used for Nakagami imaging. In the experiments on agar phantoms, an increasing scatterer concentration from 2 to 32 scatterers/mm3 led to backscattered statistics ranging from pre-Rayleigh to Rayleigh distributions, corresponding to the increase in the Nakagami parameter measured in the focal zone from 0.1 to 0.8. However, the artifacts in the far field resulted in the Nakagami parameters of various scatterer concentrations to be close to 1 (Rayleigh distribution), making Nakagami imaging difficult to characterize scatterers. In the same scatterer concentration range, multifocus Nakagami imaging with the NCA simultaneously suppressed two types of artifacts, making the Nakagami parameter increase from 0.1 to 0.8 in the focal zone and from 0.18 to 0.7 in the far field, respectively. In the breast phantom experiments, the backscattered statistics of the mass corresponded to a high degree of pre-Rayleigh distribution. The Nakagami parameter of the mass before and after artifact reduction was 0.7 and 0.37, respectively. The results demonstrated that the proposed method for artifact reduction allows a sensitive and effective scatterer characterization by Nakagami imaging.
Preliminary Thoughts on Structures of ‘Sovereignty’ and the Deepening Gap between Judaism and Christianity in the First Centuries CE
Authors: Edrei Arye , Mendels Doron
Published: March 2014

It is claimed that one important reason for the parting of the ways between Judaism and Christianity in the first centuries of the Common Era was the fact that the Christians ‘outsourced’ their legal system to their host country (e.g. Rome). At the same time, the Jews created their own ‘civil and criminal’ law-code and strictly adhered to it, inter alia, by founding their own law-courts. Their legal autonomy led to the idea of political sovereignty on the one hand, yet contributed to their speration from the gentile environment on the other. This development may also be one of the reasons that many of the Rabbis and their constituencies moved eastward to the Parthian Empire, which was—due to its feudal system—quite tolerant towards Jewish legal thought and practice. In contradistinction, Christianity was not bound by its own particularistic legal sovereignty and thus could more easily integrate in the Roman Empire. Its sovereignty was perceived as theological and not political.
The effects of billet temperature on compound extrusion of magnesium alloy by three-dimensional finite element modeling and experiments
Authors: Hu Hong-jun , Fan Jun-zhi
Published: March 2014

Extrusion–shearing of magnesium billets is associated with large deformations, high strain rates and high temperatures, which could result in many difficulties in process. Thermo-mechanically coupled three-dimensional finite element simulations of extrusion–shearing wrought magnesium alloy AZ31 into small rods at certain speed have been performed, and computed parameters including workpiece material characteristics and process conditions (billet preheated temperature, extrusion ratio, ram speed, friction factors and heat transfer coefficients) have been taken into consideration. The temperatures and stress and strain rates of extrudates with different billet preheated temperature have been calculated by finite element method software DEFORM-3D. A series of extrusion–shearing experiments and microstructure observations have been done to perform tests in order to validate the finite element method simulation results at different preheated temperatures of billets. Surface defects of rods for magnesium alloys extruded by the extrusion–shearing extrusion have been observed and analyzed. The influences of preheated temperature on the microstructures and the causes have been given. Finite element method software DEFORM-3D has been used successfully to simulate the temperatures and stress and strain rates under three different extrusion conditions. The results of these simulations helped to understand the formation of surface defects in the surface of extrusion–shearing rods. These results could assist in improving quality of extrusion–shearing extrusion.
Optimizing the train timetable for a subway system
Authors: Le Zhao , Li Keping , Ye Jingjing , Xu Xiaoming
Published: March 2014

With the development of subway systems, the utilization of regenerative braking energy has become an important issue. Focusing on the dynamic coordination of trains when regenerative braking energy is available, this paper proposes a new strategy, in which the regenerative energy generated by braking trains is used directly by accelerating trains. First, a mathematical model is formulated to optimize the metro timetable to maximize the utilization of regenerative braking energy. The model is a nonlinear integer programming problem that searches for the optimal headway and dwell time at each station. Furthermore, a simulated annealing algorithm is used to solve the optimal timetable. Finally, the Island Line of MTR (the mass transit system in Hong Kong) is taken as an example to illustrate the efficiency of the model and solution method. The results show that the utilization of regenerative braking energy can be improved by between 4 and 12% depending on the energy conversion rate. It is shown that a larger energy conversion rate results in a larger improvement.
Minimum wage systems and earnings inequalities: Does institutional diversity matter?
Authors: Garnero Andrea , Kampelmann Stephan , Rycx François
Published: March 2014

This article explores how the diversity of minimum wage systems affects earnings inequalities within European countries. It relies on the combination of harmonized microdata from household surveys, data on national statutory minimum wages and coverage rates and information on minimum rates compiled from more than 1100 sectoral-level agreements across Europe. The analysis covers 18 countries over the period 2007–2009. Empirical results confirm the intuition of many practitioners that the combination of sectoral minima and high collective bargaining coverage can be regarded as a functional equivalent of a binding statutory minimum wage, at least for earnings inequalities. Regression results suggest indeed that both a national statutory minimum and, in countries with sectoral minima, higher collective bargaining coverage is significantly associated with lower levels of (overall and inter-industry) wage inequalities and a smaller fraction of workers paid below prevailing minima. Several robustness checks confirm these findings.
Understanding Cultural Competence in a Multicultural Nursing Workforce
Authors: Almutairi Adel F. , McCarthy Alexandra , Gardner Glenn E.
Published: March 2014

Purpose: In Saudi Arabia, the health system is mainly staffed by expatriate nurses from different cultural and linguistic backgrounds. Given the potential risks this situation poses for patient care, it is important to understand how cultural diversity can be effectively managed in this multicultural environment. The purpose of this study was to explore notions of cultural competence with non-Saudi Arabian nurses working in a major hospital in Saudi Arabia. Design: Face-to-face, audio-recorded, semistructured interviews were conducted with 24 non-Saudi Arabian nurses. Deductive data collection and analysis were undertaken drawing on Campinha-Bacote’s cultural competence model. The data that could not be explained by this model were coded and analyzed inductively. Findings: Nurses within this culturally diverse environment struggled with the notion of cultural competence in terms of each other’s cultural expectations and those of the dominant Saudi culture. Discussion: The study also addressed the limitations of Campinha-Bacote’s model, which did not account for all of the nurses’ experiences. Subsequent inductive analysis yielded important themes that more fully explained the nurses’ experiences in this environment. Implications for Practice: The findings can inform policy, professional education, and practice in the multicultural Saudi setting.
Hyperammonaemia in four cats with renal azotaemia
Authors: Adagra Carl , Foster Darren J
Published: March 2014

Hyperammonaemia is well reported in animals with advanced hepatic disease and portosystemic shunts, but is unreported in cats with renal disease. This case series describes four cats with severe renal azotaemia in which elevated ammonia levels were detected during the course of treatment. In two cases hyperammonaemia was detected at a time when neurological signs consistent with encephalopathy had developed. This raises the possibility that hyperammonaemia may play a role in the development of encephalopathy in cats with renal azotaemia.
Trained vs untrained evaluator assessment of body condition score as a predictor of percent body fat in adult cats
Authors: Shoveller Anna K , DiGennaro Joe , Lanman Cynthia , Spangler Dawn
Published: March 2014

Body condition scoring (BCS) provides a readily available technique that can be used by both veterinary professionals and owners to assess the body condition of cats, and diagnose overweight or underweight conditions. The objective of this study was to evaluate a five-point BCS system with half-point delineations using dual-energy x-ray absorptiometry (DXA). Four evaluators (a veterinarian, veterinary technician, trained scorer and untrained scorer) assessed 133 neutered adult cats. For all scorers, BCS score was more strongly correlated with percent body fat than with body weight. Percent body fat increased by approximately 7% within each step increase in BCS. The veterinarian had the strongest correlation coefficient between BCS and percent fat (r = 0.80). Mean body fat in cats classified as being in ideal body condition was 12 and 19%, for 3.0 and 3.5 BCS, respectively. Within BCS category, male cats were significantly heavier in body weight than females within the same assigned BCS category. However, DXA-measured percent body fat did not differ significantly between male and female cats within BCS category, as assigned by the veterinarian ( P >0.13). Conversely, when assessed by others, mean percent body fat within BCS category was lower in males than females for cats classified as being overweight (BCS >4.0). The results of this study show that using a BCS system that has been validated within a range of normal weight to moderately overweight cats can help to differentiate between lean cats and cats that may not be excessively overweight, but that still carry a higher proportion of body fat.
Temporary mineralocorticoid receptor antagonism during the development of hypertension improves cerebral artery dilation
Authors: McClain Jonathon L , Dorrance Anne M
Published: March 2014

Hypertension causes cerebral artery remodeling and increases the risk of stroke. Renin angiotensin system blockade during the development of hypertension has therapeutic effects even after treatment withdrawal. Mineralocorticoid receptor (MR) activation has been implicated in artery remodeling and impaired endothelial function. The possibility that there is a critical therapeutic window for MR antagonism has not been investigated. We hypothesized that temporary MR antagonism while hypertension develops would improve middle cerebral artery (MCA) structure and function in stroke-prone spontaneously hypertensive rats (SHRSP), even after treatment withdrawal. Six-week-old SHRSP were treated with spironolactone (25 mg/kg/day) from 6 to 12 weeks and when aged to 18 weeks, these rats were compared to age-matched untreated SHRSP. Surprisingly, temporary spironolactone treatment reduced the MCA outer and lumen diameter but had no effect on the wall thickness. Temporary spironolactone treatment improved nitric oxide and endothelium-derived hyperpolarizing factor mediated dilation but had no effect on blood pressure. Spironolactone treatment caused a very small reduction in the damage caused by permanent focal cerebral ischemia. These results suggest that temporary MR antagonism during the development of hypertension has divergent effects on the MCA, in that it causes a potentially detrimental reduction in the lumen diameter while improving vasodilation.
Sarcopenia, malnutrition and nutrient density in older people
Authors: Smith Alison
Published: March 2014

Both sarcopenia and malnutrition can have a significant impact on health and functional status in older people. Good nutrition and physical activity throughout life are protective factors. In addition to inadequate nutrient intake, reduced physical activity is known to increase the risk of developing sarcopenia. Progressive resistance training has been shown to be an effective intervention and there is also significant potential for whole diet interventions, many of which are also effective in treating malnutrition.
Early onset of Chanarin-Dorfman syndrome with severe liver involvement in a patient with a complex rearrangement of ABHD5 promoter
Authors: Missaglia Sara , Valadares Eugenia Ribeiro , Moro Laura , Faguntes Eleonora Druve Tavares , quintão Roque Raquel , Giardina Bruno , Tavian Daniela
Published: March 2014

Background

α/β-hydrolase domain-containing protein 5 (ABHD5) plays an important role in the triacylglycerols (TAG) hydrolysis. Indeed, ABHD5 is the co-activator of adipose triglyceride lipase (ATGL), that catalyses the initial step of TAG hydrolysis. Mutations in ABHD5 gene are associated with the onset of Chanarin-Dorfman syndrome (CDS), a rare autosomal recessive lipid storage disorder, characterized by non-bullous congenital ichthyosiform erythroderma (NCIE), hepatomegaly and liver steatosis.

Case presentation

We describe here a 5-years-old Brazilian child who presented with NCIE at birth and diffuse micro and macro-vesicular steatosis on liver biopsy since she was 2 years old. Molecular analysis of coding sequence and putative 5′ regulatory region of ABHD5 gene was performed. A homozygous novel deletion, affecting the promoter region and the exon 1, was identified, confirming the suspected diagnosis of CDS for this patient. RT-PCR analysis showed that the genomic rearrangement completely abolished the ABHD5 gene expression in the patient, while only a partial loss of expression was detected in her parents. This is the first report describing the identification of a large deletion encompassing the promoter region of ABHD5 gene. The total loss of ABHD5 expression may explain the early onset of CDS and the severe liver involvement. After molecular diagnosis, the patient started a special diet, poor in fatty acids with medium chain triglycerides (MCT), and showed hepatic and dermatologic improvement in spite of severe molecular defect.

Conclusions

This case report extends the spectrum of disease-causing ABHD5 mutations in CDS providing evidence for a novel pathogenic mechanism for this rare disorder. Moreover, our preliminary data show that early diagnosis and prompt treatment of neutral lipid accumulation might be useful for CD patients.
Nanoscale changes in chromatin organization represent the initial steps of tumorigenesis: a transmission electron microscopy study
Authors: Cherkezyan Lusik , Stypula-Cyrus Yolanda , Subramanian Hariharan , White Craig , Dela Cruz Mart , Wali Ramesh K , Goldberg Michael J , Bianchi Laura K , Roy Hemant K , Backman Vadim
Published: March 2014

Background

Nuclear alterations are a well-known manifestation of cancer. However, little is known about the early, microscopically-undetectable stages of malignant transformation. Based on the phenomenon of field cancerization, the tissue in the field of a tumor can be used to identify and study the initiating events of carcinogenesis. Morphological changes in nuclear organization have been implicated in the field of colorectal cancer (CRC), and we hypothesize that characterization of chromatin alterations in the early stages of CRC will provide insight into cancer progression, as well as serve as a biomarker for early detection, risk stratification and prevention.

Methods

For this study we used transmission electron microscopy (TEM) images of nuclei harboring pre-neoplastic CRC alterations in two models: a carcinogen-treated animal model of early CRC, and microscopically normal-appearing tissue in the field of human CRC. We quantify the chromatin arrangement using approaches with two levels of complexity: 1) binary, where chromatin is separated into areas of dense heterochromatin and loose euchromatin, and 2) grey-scale, where the statistics of continuous mass-density distribution within the nucleus is quantified by its spatial correlation function.

Results

We established an increase in heterochromatin content and clump size, as well as a loss of its characteristic peripheral positioning in microscopically normal pre-neoplastic cell nuclei. Additionally, the analysis of chromatin density showed that its spatial distribution is altered from a fractal to a stretched exponential.

Conclusions

We characterize quantitatively and qualitatively the nanoscale structural alterations preceding cancer development, which may allow for the establishment of promising new biomarkers for cancer risk stratification and diagnosis. The findings of this study confirm that ultrastructural changes of chromatin in field carcinogenesis represent early neoplastic events leading to the development of well-documented, microscopically detectable hallmarks of cancer.
Dynamic constrained coalition formation among electric vehicles
Authors: de O Ramos Gabriel , Burguillo Juan C , Bazzan Ana LC
Published: March 2014

Background

The use of electric vehicles (EVs) and vehicle-to-grid (V2G) technologies have been advocated as an efficient way to reduce the intermittency of renewable energy sources in smart grids. However, operating on V2G sessions in a cost-effective way is not a trivial task for EVs. The formation of coalitions among EVs has been proposed to tackle this problem.

Methods

In this paper we introduce Dynamic Constrained Coalition Formation (DCCF), which is a distributed heuristic-based method for constrained coalition structure generation (CSG) in dynamic environments. In our approach, coalitions are formed observing constraints imposed by the grid. To this end, EV agents negotiate the formation of feasible coalitions among themselves.

Results

Based on experiments, we show that DCCF is efficient to provide good solutions in a fast way. DCCF provides solutions whose quality approaches 98% of the optimum. In dynamically changing scenarios, DCCF also shows good results, keeping the agents payoff stable along time.

Conclusions

Essentially, DCCF’s main advantage over traditional CSG algorithms is that its computational effort is very lower. On the other hand, unlike traditional algorithms, DCCF is suitable only for constraint-based problems.