bluuebunny/crossref_metadata_2025 huggingface dataset:
Lipid Droplet Analysis Using In Vitro Bovine Oocytes and Embryos
Authors: Ordoñez‐Leon EA , Merchant H , Medrano A , Kjelland M , Romo S
Published: January 2014

Contents

The aim of this study was to quantify the content of lipid droplets in bovine oocytes and embryos from Bos indicus (Bi), Bos taurus (Bt) and Bos indicus × Bos taurus (Bi × Bt). Oocytes were aspirated post‐mortem and subjected to in vitro maturation, in vitro fertilization and in vitro development; the medium employed at each stage (TCM‐199, TALP, SOF) was supplemented with (i) serum replacement (SR), (ii) foetal calf serum (FCS) or (iii) oestrous cow serum (ECS). The structure and distribution of the lipid droplets were established using electron microscopy, but were quantified using an optical microscope on semi‐fine toluidine blue‐stained sections. The highest percentage of embryos corresponded to those produced with FCS and ECS, which differed from embryos generated with SR (p < 0.05). The highest percentage of morulae and the lowest percentage of blastocysts were obtained with the SR supplement (p < 0.05). The oocytes cultured in FCS demonstrated a higher number of lipid droplets compared to those cultured in SR and ECS (p < 0.05). Less accumulation of lipids was observed in embryos supplemented with SR. The lowest and highest numbers of lipid droplets in oocytes corresponded to the Bi and Bt strain, respectively. The lowest amount of lipid droplets in embryos was observed in Bi (p < 0.05). In conclusion, supplementation of the in vitro development culture medium (synthetic oviduct fluid) with a synthetic substitute serum produced similar results in terms of embryo development compared to those obtained with FCS, but a decreased degree of lipid droplet accumulation was observed in the in vitro‐cultured embryos.
Must‐See TV: South Asian Characterizations in American Popular Media
Authors: Thakore Bhoomi K.
Published: January 2014

In the 21st century, representations of South Asians in American popular television have increased significantly. However, there has been very little critical analysis on the ways in which these characters are created and produced. In this review, I use literature from the sociology of race/ethnicity, immigration, and critical media studies to identify the concept of “(ethnic) characterization.” While it may be assumed that these representations are created unconsciously, I suggest that media producers intentionally use particular ethnic characteristics that are identified and discussed in contemporary sociological literature. As a result, I argue that these types of media characterizations are relevant to the discipline of sociology.
An Oceanic revolution? Stella and the construction of new femininities in Papua New Guinea and the Pacific
Authors: Spark Ceridwen
Published: January 2014

In August 2012, a new magazine for women was released in Papua New Guinea (PNG). Entitled Stella, the magazine provides an ideal opportunity to analyse shifting constructions of gender among educated, employed women in PNG and elsewhere in the Pacific. Drawing on interviews, surveys and readers’ letters, this article discusses Papua New Guinean women who, because they display ‘modern attributes’, are maligned and discredited as ‘inauthentic’. It then goes on to document the ways in which Stella is enabling such women to assert themselves anew. Arguing that the publication of Stella marks the arrival into the public sphere of a group hitherto consigned to the margins of Pacific societies on the basis that they represent an ‘inauthentic minority’, the article makes an important contribution to scholarly discussion about the emergence of new femininities in PNG and the Pacific.
A genotypic difference in primary root length is associated with the inhibitory role of transforming growth factor‐beta receptor‐interacting protein‐1 on root meristem size in wheat
Authors: He Xue , Fang Jingjing , Li Jingjuan , Qu Baoyuan , Ren Yongzhe , Ma Wenying , Zhao Xueqiang , Li Bin , Wang Daowen , Li Zhensheng , Tong Yiping
Published: January 2014

Previously we identified a major quantitative trait locus (QTL) qTaLRO‐B1 for primary root length (PRL) in wheat. Here we compare proteomics in the roots of the qTaLRO‐B1 QTL isolines 178A, with short PRL and small meristem size, and 178B, with long PRL and large meristem size. A total of 16 differentially expressed proteins were identified: one, transforming growth factor (TGF)‐beta receptor‐interacting protein‐1 (TaTRIP1), was enriched in 178A, while various peroxidases (PODs) were more abundantly expressed in 178B. The 178A roots showed higher TaTRIP1 expression and lower levels of the unphosphorylated form of the brassinosteroid (BR) signaling component BZR1, lower expression of POD genes and reduced POD activity and accumulation of the superoxide anion O2− in the root elongation zone compared with the 178B roots. Low levels of 24‐epibrassinolide increased POD gene expression and root meristem size, and rescued the short PRL phenotype of 178A. TaTRIP1 directly interacted with the BR receptor TaBRI1 of wheat. Moreover, overexpressing TaTRIP1 in Arabidopsis reduced the abundance of unphosphorylated BZR1 protein, altered the expression of BR‐responsive genes, inhibited POD activity and accumulation of the O2− in the root tip and inhibited root meristem size. Our data suggested that TaTRIP1 is involved in BR signaling and inhibited root meristem size, possibly by reducing POD activity and accumulation of O2− in the root tip. We further demonstrated a negative correlation between the level of TaTRIP1 mRNA and PRL of landraces and modern wheat varieties, providing a valuable insight for better understanding of the molecular mechanism underlying the genotypic differences in root morphology of wheat in the future.
Comparison of feline core bone marrow biopsies from different sites using 2 techniques and needles
Authors: Abrams‐Ogg Anthony C. G. , Defarges Alice , Bienzle Dorothee
Published: January 2014

Background

Commonly used 11ga or 13ga biopsy needles are relatively large for cats and often preclude successful collection of bone marrow (BM) core biopsies.

Objectives

The objective was to compare 15ga to 13ga BM core biopsy ease of collection and specimen quality.

Methods

In 10 cats, humeral biopsies obtained with 15ga EZ‐IO needles were compared with iliac biopsies obtained with 13ga Jamshidi needles. Body condition, ease of collection, section quality, postprocedure pain, and swelling at biopsy sites were scored. Specimen length on mounted slides was measured and specimens with quality scores of 3–5 out of a maximum value of 5 were considered to be of acceptable diagnostic quality. The distribution of all parameters was assessed by Shapiro–Wilk tests, and differences in parameters were assessed by ANCOVA.

Results

There were no significant differences between 15ga and 13ga biopsies, except that the 15ga humeral biopsy was judged to be easier to perform than 13ga iliac biopsy, and there was more severe postbiopsy swelling with 13ga biopsies. Facility score (mean ± SD), section quality score (median ± SD) and specimen length (mm, mean ± SD) were 12.7 ± 2.3, 2.0 ± 1.4, and 6.0 ± 2.1 for 15ga biopsies, respectively, and 8.9 ± 2.4, 1.0 ± 1.8, and 7.5 ± 2.5 for 13ga biopsies, respectively. Three specimens of acceptable quality were obtained with each 15ga and 13ga biopsies.

Conclusions

In cats, BM biopsy of the humerus with a 15ga needle is easier and causes less postbiopsy swelling than biopsy of the ilium with a 13ga needle. Sites and needles are equivalent with respect to yielding specimens of acceptable quality. Neither technique consistently captured high‐quality specimens.
Comparative study of select biochemical markers in cerebrospinal fluid of healthy dogs before and after treatment with nutraceuticals
Authors: Galan A. , Carletti B.E. , Morgaz J. , Granados M.M. , Mesa I. , Navarrete R. , Lombardo R. , Martínez C.M. , Martín‐Suárez E.M.
Published: January 2014

Background

Several studies indicate that changes in cerebrospinal fluid (CSF) composition depend on the disease stage and reflect modification of brain energy metabolism (BEM). Also, it has been reported that a decline in cognitive functions may be mitigated by incorporating nutraceuticals in the diet.

Objective

Assuming the beneficial effect of nutraceuticals on BEM and oxidative damage, the aim of this study was to determine if the administration of a nutraceutical compound results in changes of select CSF biomarkers in healthy adult Beagle dogs.

Methods

Two separate CSF and blood samples were obtained from 11 healthy adult Beagle dogs, before and after 50 days of treatment with a veterinary combined nutraceutical. CSF analysis included a total nucleated cell count, total protein, glucose, sodium, chloride, potassium, pyruvate, and lactate concentrations, and calculation of lactate/pyruvate ratio. CBC and serum biochemistry were also performed. The Wilcoxon test was used to analyze the significance of the changes after nutraceutical treatment.

Results

All studied variables remained within reference intervals, before and after treatment. A significant increase in CSF sodium and glucose concentration, and a decrease in lactate levels, was observed after treatment (P < .05), and the lactate/pyruvate ratio was decreased after treatment (P = .05). In serum, sodium and chloride concentrations were significantly increased (P < .05), and creatinine concentration was significantly decreased (P < .05) after treatment.

Conclusions

After 50 days of treatment with a nutraceutical compound, CSF glucose, sodium, and lactate concentrations, and L/P ratio were significantly different, suggesting an influence of nutraceuticals' administration on CSF composition.
Stability of immunophenotypic lymphoid markers in fixed canine peripheral blood for flow cytometric analysis
Authors: Cian Francesco , Guzera Maciej , Frost Simon , Van Poucke Stefaan , Comazzi Stefano , Archer Joy
Published: January 2014

Background

Flow cytometric analysis of blood samples for immunophenotyping lymphoproliferative diseases has become popular in veterinary medicine. Unfortunately, the use of this technique has been limited by the necessity to test samples within a short time frame after blood collection. A possible solution to this problem is the use of fixative products to preserve the stability of lymphoid antigens.

Objectives

The aim of this study was to evaluate the expression of 5 lymphoid surface markers (CD3, CD4, CD8, CD21, and CD45) in blood samples collected in K3‐EDTA and Cyto‐Chex BCT tubes from healthy dogs.

Methods

Blood from 8 dogs was collected in K3‐EDTA and Cyto‐Chex BCT tubes and analyzed by flow cytometry at 6 hours, one day, 3 days, and 7 days after collection. Lymphocyte percentage, lymphocyte mor‐phology, expression of lymphoid surface markers and mean fluorescence intensity (MFI) were recorded at each time point and compared.

Results

Lymphocyte percentage and morphology were preserved up to 3 days in samples collected in Cyto‐Chex BCT, and lymphocyte percentage was mildly decreased on day 7. CD4, CD8, and CD21 were stable in Cyto‐Chex BCT up to 7 days, whereas CD3 and CD45 showed a significant decrease in expression from day 3, with a decrease on average of 21% and 2.4%, respectively, on day 7. MFI was significantly decreased on day 7 for all markers except CD21.

Conclusions

These findings indicate that storage of samples in Cyto‐Chex BCT affects lymphoid marker expression and caution should be exercised when interpreting data produced on such samples.
Systematic evaluation of evidence on veterinary viscoelastic testing Part 2: Sample acquisition and handling
Authors: Flatland Bente , Koenigshof Amy M. , Rozanski Elizabeth A. , Goggs Robert , Wiinberg Bo
Published: January 2014

Objective

To examine systematically the evidence on sample acquisition and handling for the thrombo elastography (TEG) and rotational thromboelastometry (ROTEM) viscoelastic point of care instruments and to identify knowledge gaps.

Design

Six questions were considered, addressing sampling site, collection system, anticoagulant, collection procedure, and sample storage. Standardized, systematic evaluation of the literature was performed. Relevant articles were categorized according to level of evidence (LOE). Consensus was developed regarding conclusions for application of concepts to clinical practice.

Setting

Academic and referral veterinary medical centers.

Results

PubMed and CAB abstracts were searched. Eighteen papers were initially chosen; 5 of these papers applied to > 1 domain question. Three papers were used to address 2 questions each, and 2 papers were used to address 3 questions each. Most papers were judged LOE 3 (Good or Fair). Two of 5 papers were judged to be the same LOE each time they were used; 2 papers were judged to be LOE 3, Fair for 1 question and 3, Good for a second question; 1 paper used to address 3 questions was judged LOE 3, Good twice and 3, Fair once. Fourteen additional papers were evaluated post hoc during manuscript preparation.

Conclusions

Jugular venipuncture is recommended, but samples from IV catheters can be used. Consistent technique is important for serial sampling, and standardized sampling protocols are recommended for individual centers performing TEG/ROTEM. There is insufficient evidence to recommend use of a specific blood collection system, although use of evacuated blood tubes and 21‐Ga or larger needles is suggested. Use of 3.2% buffered sodium citrate in a strict 1:9 ratio of citrate to blood is suggested. Suggested tube draw order is discard/serum, followed by citrate, EDTA, and then heparin. Samples should be held at room temperature for 30 minutes prior to analysis.
Systematic evaluation of evidence on veterinary viscoelastic testing Part 4: Definitions and data reporting
Authors: Hanel Rita M. , Chan Daniel L. , Conner Bobbi , Gauthier Vincent , Holowaychuk Marie , Istvan Stephanie , Walker Julie M. , Wood Darren , Goggs Robert , Wiinberg Bo
Published: January 2014

Objective

To systematically examine evidence surrounding definitions and reporting of data for viscoelastic testing in veterinary medicine.

Design

Standardized, systematic evaluation of the literature, categorization of relevant articles according to level of evidence and quality, and development of consensus on conclusions for application of the concepts to clinical practice.

Setting

Academic and referral veterinary medical centers.

Results

Databases searched included Medline, CAB abstracts, and Google Scholar.

Conclusions

All 4 standard thromboelastography (TEG) and rotational thromboelastometry (ROTEM) variables should be universally reported, and the reporting of shear elastic modulus in addition to maximum amplitude (MA) is encouraged. There is insufficient evidence to support universal usage of the coagulation index at this time. The K value and clot formation time are the most variable of the 4 parameters, with alpha angle, MA, and maximum clot firmness generally the least variable. Individual studies should report sufficient data on patients and institutional controls to enable definitions of hypo‐ and hypercoagulability to be evaluated post‐hoc, and it is recommended that all studies specifically report how these conditions were defined. In reporting data relating to fibrinolysis, the TEG variables LY30, LY60, CL30, CL60, and the ROTEM variables LI30, LI60, ML, LOT, and LT should be documented. Studies should report sufficient data on patients and controls to enable definitions of hyper‐ and hypofibrinolysis to be evaluated post‐hoc, and we suggest that standard TEG/ROTEM assays may be unable to detect hypofibrinolysis in companion animals. We recommend that every center establish reference intervals, which are specific to either TEG or ROTEM. These reference intervals should be established using veterinary clinical pathology guidelines, standardized protocols, and a minimum of 40 healthy animals. There are currently insufficient data in companion animals to suggest a utility for Vcurve variables beyond that of standard TEG variables.
Soft Switch Lock-Release Mechanism for a Switch-Mode Hydraulic Pump Circuit
Authors: Van de Ven James D.
Published: January 2014

Switch-mode hydraulic circuits are a theoretically efficient, compact, fast responding, and inexpensive control option. Despite the many potential benefits of switch-mode hydraulic circuits, the control method suffers from large energy losses during transitions of the high-speed valve due to throttling and fluid compressibility. Rannow and Li previously proposed utilizing soft switching to minimize the throttling energy loss (Rannow and Li, “Soft Switching Approach to Reducing Transition Losses in On/Off Hydraulic Valve,” J. Dyn. Syst., Measure. Control (in press)). A major challenge of this approach is a locking soft switch that releases quickly and with precise timing, while under load. In this paper, a novel soft switch locking mechanism is presented that utilizes the pressure signal in the switched volume to trigger the release. A dynamic model is developed of three unique soft switch circuits and two control circuits that create a virtually variable displacement pump. The model is used to perform a grid search optimization of the soft switch parameters for the three circuits. The three soft switch circuits reduce the throttling and compressibility energy losses between 49% and 66% compared with the control circuit. The simulation results demonstrated that the soft switch circuits perform as expected for duty cycles and pressures below the design conditions. At higher duty cycles and pressures, the short time the circuit is connected to tank prevented the soft switches from resetting between cycles, preventing proper function. This novel lock and release soft switch mechanism enables soft switching in switch-mode hydraulic circuits, which significantly reduces throttling and compressibility energy losses during valve transitions. Lower losses during valve transition allow the use of slower switching valves, lowering energy consumption, and cost.
Steerable Guidewire for Magnetic Resonance Guided Endovascular Interventions
Authors: Clogenson H. C. M. , Dankelman J. , van den Dobbelsteen J. J.
Published: January 2014

In endovascular interventions, thin, flexible instruments are inserted through the skin into the blood vessels to diagnose and treat various diseases of the vascular system. One drawback is that the instruments are difficult to maneuver in the desired direction due to limitations in shape and flexibility. Another disadvantage is that the interventions are performed under intermittent fluoroscopy/angiography imaging. Magnetic resonance imaging (MRI) may offer advantages over X-ray guidance. It presents a good soft tissue contrast without the use of nephrotoxic media or ionizing radiation. The aim of this study is to develop a guidewire that is compatible with MRI and includes a steerable segment at the tip. This added degree-of-freedom may improve the maneuverability of the devices thereby the efficiently and safety of the navigation. A 1.6 m (5 ft, 3 in.) long and 0.035 in. diameter guidewire that consists of MR compatible materials and has a flexible tip was designed. The only metallic part was a nitinol rod that was implemented at the distal flexible tip. To limit the risk of heating in the MRI, this rod was kept shorter than 30 mm. The tip could be deflected in one direction by pulling on a Dyneema wire that was placed in the lumen of the shaft of the guidewire. To drive the steerable tip, a handle that could be easily attached/detached from the instrument was designed and implemented. Using the handle, the tip of the 1.60 m long guidewire prototype could be actuated to reach angles from 30 deg to 250 deg. The handle could easily be placed on and removed from the guidewire, so conventional 0.035 in.–compatible catheters could slide over from the proximal end. However, in order to make the guidewire more efficient to enter a bifurcation, the stiffness of the tip should progressively increase from its proximal to its distal end. The guidewire was imaged in a 1.5T MRI using real-time imaging without producing artifacts that would have shaded the anatomy. It was possible to assemble a guidewire with a steerable segment in the required size, using MR compatible materials. Therefore, the current design is a promising proof of concept and allowed us to clearly identify the features that need to be improved in order to come to a clinically applicable instrument.
Factors That Affect Welding-Induced Residual Stress and Distortions in Pressure Vessel Steels and Their Mitigation Techniques: A Review
Authors: Zondi M. Clyde
Published: January 2014

Pressure vessels comprise critical plant equipment within industrial operations. The fact that the vessel operates under pressure, and may carry toxic, dangerous or hazardous contents, necessitates that care is taken to ensure safety of humans operating it and the environment within which it operates. Residual stress developed during welding of pressure vessel structures adversely affects fatigue life of such structure by reducing fracture toughness. Formation of residual stresses during welding occurs when nonuniform heating of the metallic surfaces produces substantial temperature gradients, which in turn cause plastic straining of the different portions of the weld-piece material, thereby subjecting it to postcooling internal stresses that are likely to weaken it. A number of studies have been performed on welding parametric analysis with the help of design of experiments (DoE), mathematical programming, evolutionary algorithms and finite element methods, with the intention to quantify effects of welding factors on resultant residual stress. The objective of this review is to organize such literature according to the specific areas of analysis in order to enhance access thereto and elucidate relevance thereof for purposes of reference work and further studies. The paper specifies three categories of influential factors as prewelding conditions, in-process parameters, and postwelding conditions. It is shown that prewelding conditions, such as the choice of welding process, must be chosen in line with the nature of materials to be welded, operational application of the structure, and trade-offs between service life and production costs. Heat input (which is the function of arc voltage, welding current, and travel speed) is the most influential machine-related in-process parameter in the residual stress generation during welding. It is also observed that when applying mitigating factors, care should be taken not to exacerbate the residual stress situation through suboptimal parametric set-up.
Forces Exerted on a Cylinder in Near-Axial Flow
Authors: Divaret Lise , Moussou Pierre , Berland Julien , Berro Hassan , Cadot Olivier , Doaré Olivier
Published: January 2014

This study investigates the flow around a cylinder in a near-axial flow at a Reynolds number of 27,000. Both computational fluid dynamics (CFD) calculations and experiments are performed. Time-mean values of lift force coefficient are investigated against the inclination of the cylinder in the domain of low inclinations (<15 deg). A pressure distribution and flow profiles are also measured and extracted from the CFD calculation results for a characteristic inclination α = 5 deg. Numerical results for force and pressure show fair agreement with experiments for inclination below 5 deg and reveal that at low angles, the lift force is proportional to the angle. In the framework of a quasi-static approach, the instantaneous damping force exerted on a cylinder oscillating in axial flow is equivalent to the normal force exerted on a cylinder placed in an oblique flow.
Technical and Economic Feasibility Analysis of Using Concentrated Solar Thermal Technology in the Cement Production Process: Hybrid Approach—A Case Study
Authors: Sebastián González Ricardo , Flamant Gilles
Published: January 2014

This work describes the evaluation of concentrated solar thermal (CST) in a conventional cement plant in order to replace from 40% to 100% of the thermal energy required in the process. By using CST at the calcination process in the cement production line, CO2 emissions can be reduced by 40%. The aim of the study is not to propose a detailed design of the solar process but to examine and quantify the various options in order to define the favorable economic conditions and the technical issues to face in a conventional cement plant aiming: substituting energy sources and achieving continuous operation of the cement plant employing a hybrid mode.
Fracture Mode Transition for Explosively Loaded GB/JB 20 Steel Containment Vessels
Authors: Li Ma , Yang Hu , Yang Du , Jinyang Zheng
Published: January 2014

A rupture experiment was conducted on cylindrical explosion containment vessels (ECVs), where the fracture mode transition was observed. Microstructure examinations indicate the material GB/JB20 (AISI 1020) experienced a fibrous-to-cleavage fracture mechanism transition with increment of loading rate. Different from fracture mechanics method, a rate-dependent failure criterion is proposed to account for the dynamic fracture behavior, which is compatible with experimental observation that the material fails at low effective plastic strain when at high strain rates. A finite element analysis of a cylindrical containment vessel with different sizes of initial cracks was performed, where the overpressure caused by detonation was calculated, and the dynamic crack propagation and fracture mode transition were reproduced. In addition, a failure assessment including the estimation of limiting crack sizes corresponding to impulsive loading was conducted. It was found that a small variation of initial crack size has minor influence on the final fracture mode and profile, which is mainly dependent upon the intensity of impulsive load as well as the loading rate. The results also indicate that the crack propagates with strongly nonlinear speeding, most cracking length developed during the first structural vibration cycle.
Study of Characteristics of Cloud Cavity Around Axisymmetric Projectile by Large Eddy Simulation
Authors: Yu Xianxian , Huang Chenguang , Du Tezhuan , Liao Lijuan , Wu Xiaocui , Zheng Zhi , Wang Yiwei
Published: January 2014

Cavitation generally occurs where the pressure is lower than the saturated vapor pressure. Based on large eddy simulation (LES) methodology, an approach is developed to simulate dynamic behaviors of cavitation, using k-μ transport equation for subgrid terms combined with volume of fluid (VOF) description of cavitation and the Kunz model for mass transfer. The computation model is applied in a 3D field with an axisymmetric projectile at cavitation number σ = 0.58. Evolution of cavitation in simulation is consistent with the experiment. Clear understanding about cavitation can be obtained from the simulation in which many details and mechanisms are present. The phenomenon of boundary separation and re-entry jet are observed. Re-entry jet plays an important role in the bubble shedding.
Coupling Between Roll Motions of an FLNG Vessel and Internal Sloshing
Authors: Zhao Wenhua , Yang Jianmin , Hu Zhiqiang , Tao Longbin
Published: January 2014

A series of two-dimensional model tests has been conducted to study the coupling between global roll motions of a floating liquefied natural gas (FLNG) vessel and internal sloshing. The model of the FLNG is allowed to move freely in roll under the excitations of an initial heel angle, band-limited waves, and regular waves. To clarify the coupling effects, the FLNG vessel in different filling conditions is ballasted in fresh water and equivalent steel ballast weights, respectively. Time series of both the internal sloshing and the global motions of the vessel are measured. Statistical and spectral analyses have been carried out on the measured data. Sloshing oscillations in different surface modes have been observed. Asymmetry of the internal wave profile relative to still-water surface is also observed. Attempts are made to clarify the influences of the internal sloshing on the global roll motions through the comparison of the experiment results between the liquid and steel ballasting cases. The coupling phenomenon is found to be sensitive to the period and height of excitation waves. Further discussion has been made on the experiment results, and some conclusions regarding the coupling mechanism between global motions and internal sloshing are drawn based on the present study.
Onset of Flow Induced Tonal Noise in Corrugated Pipe Segments
Authors: Rudenko Oleksii , Nakiboğlu Güneş , Hirschberg Avraham
Published: January 2014

Corrugated pipes combine small-scale rigidity and large-scale flexibility, which make them very useful in industrial applications. The flow through such a pipe can induce strong undesirable tonal noise (whistling) and even drive integrity threatening structural vibrations. Placing a corrugated segment along a smooth pipe reduces the whistling, while this composite pipe still retains some global flexibility. The whistling is reduced by thermoviscous damping in the smooth pipe segment. For a given corrugated segment and flow velocity, one would like to predict the smooth pipe length just sufficient to avoid tonal noise: the onset of whistling. A linear model based on empirical data is proposed that predicts the conditions at the onset of whistling for a composite pipe at moderately high Reynolds numbers, Re: 3000<Re<100,000. Experimental results for corrugated pipes of eight different corrugation geometries are presented revealing fair agreement with the theory. Based on these results, a universal qualitative prediction tool is obtained valid for corrugated pipe segments long compared to the acoustic wave-length.
Metal-insulator-metal capacitors based on lanthanum oxide high-κ dielectric nanolayers fabricated using dense plasma focus device
Authors: Mangla Onkar , Srivastava Asutosh , Malhotra Yashi , Ostrikov Kostya (Ken)
Published: January 2014

Metal-insulator-metal (MIM) capacitors with lanthanum oxide (La2O3) high-κ dielectric, for potential applications in mixed-signal integrated circuit (IC), have been fabricated using a dense plasma focus device. The electrical characteristics and morphological properties of the fabricated nanodevices are studied. The MIM capacitors were further annealed to enhance the electrical properties in terms of the low leakage current density, the high capacitance density, and the improved capacitance voltage linearity. The minimum leakage current densities of ∼1.6 × 10−9 A/cm2 and ∼2.0 × 10−10 A/cm2 at −1 V are obtained along with the maximum capacitance densities of ∼17.96 fF/μm2 at 100 kHz and ∼19.10 fF/μm2 at 1 MHz, 0 V for as-fabricated and annealed MIM capacitors having 15 nm thick dielectric layers as measured using ellipsometry. The nanofilms with the minimum root mean square roughness of ∼10 nm are examined using atomic force microscopy. The results are superior compared to some other MIM capacitors and can be optimized to achieve the best electrical parameters for potential applications in radio frequency (RF)/mixed signal ICs. The high frequency C-V measurements indicate an increase in the capacitance density upon increasing the frequency which supports the possibility of potential high-frequency/RF applications of the MIM capacitors.
Magnetoacoustic tomography with magnetic induction for high‐resolution bioimepedance imaging through vector source reconstruction under the static field of MRI magnet
Authors: Mariappan Leo , Hu Gang , He Bin
Published: January 2014

Purpose:

Magnetoacoustic tomography with magnetic induction (MAT‐MI) is an imaging modality to reconstruct the electrical conductivity of biological tissue based on the acoustic measurements of Lorentz force induced tissue vibration. This study presents the feasibility of the authorsˈ new MAT‐MI system and vector source imaging algorithm to perform a complete reconstruction of the conductivity distribution of real biological tissues with ultrasound spatial resolution.

Methods:

In the present study, using ultrasound beamformation, imaging point spread functions are designed to reconstruct the induced vector source in the object which is used to estimate the object conductivity distribution. Both numerical studies and phantom experiments are performed to demonstrate the merits of the proposed method. Also, through the numerical simulations, the full width half maximum of the imaging point spread function is calculated to estimate of the spatial resolution. The tissue phantom experiments are performed with a MAT‐MI imaging system in the static field of a 9.4 T magnetic resonance imaging magnet.

Results:

The image reconstruction through vector beamformation in the numerical and experimental studies gives a reliable estimate of the conductivity distribution in the object with a ∼1.5 mm spatial resolution corresponding to the imaging system frequency of 500 kHz ultrasound. In addition, the experiment results suggest that MAT‐MI under high static magnetic field environment is able to reconstruct images of tissue‐mimicking gel phantoms and real tissue samples with reliable conductivity contrast.

Conclusions:

The results demonstrate that MAT‐MI is able to image the electrical conductivity properties of biological tissues with better than 2 mm spatial resolution at 500 kHz, and the imaging with MAT‐MI under a high static magnetic field environment is able to provide improved imaging contrast for biological tissue conductivity reconstruction.
The effect of excitation and preparation pulses on nonslice selective 2D UTE bicomponent analysis of bound and free water in cortical bone at 3T
Authors: Li Shihong , Chang Eric Y. , Bae Won C. , Chung Christine B. , Hua Yanqing , Zhou Yi , Du Jiang
Published: January 2014

Purpose:

The purpose of this study was to investigate the effect of excitation, fat saturation, long T2 saturation, and adiabatic inversion pulses on ultrashort echo time (UTE) imaging with bicomponent analysis of bound and free water in cortical bone for potential applications in osteoporosis.

Methods:

Six bovine cortical bones and six human tibial midshaft samples were harvested for this study. Each bone sample was imaged with eight sequences using 2D UTE imaging at 3T with half and hard excitation pulses, without and with fat saturation, long T2 saturation, and adiabatic inversion recovery (IR) preparation pulses. Single‐ and bicomponent signal models were utilized to calculate the T2*s and/or relative fractions of short and long T2*s.

Results:

For all bone samples UTE T2* signal decay showed bicomponent behavior. A higher short T2* fraction was observed on UTE images with hard pulse excitation compared with half pulse excitation (75.6% vs 68.8% in bovine bone, 79.9% vs 73.2% in human bone). Fat saturation pulses slightly reduced the short T2* fraction relative to regular UTE sequences (5.0% and 2.0% reduction, respectively, with half and hard excitation pulses for bovine bone, 6.3% and 8.2% reduction, respectively, with half and hard excitation pulses for human bone). Long T2 saturation pulses significantly reduced the long T2* fraction relative to regular UTE sequence (18.9% and 17.2% reduction, respectively, with half and hard excitation pulses for bovine bone, 26.4% and 27.7% reduction, respectively, with half and hard excitation pulses for human bone). With IR‐UTE preparation the long T2* components were significantly reduced relative to regular UTE sequence (75.3% and 66.4% reduction, respectively, with half and hard excitation pulses for bovine bone, 87.7% and 90.3% reduction, respectively, with half and hard excitation pulses for human bone).

Conclusions:

Bound and free water T2*s and relative fractions can be assessed using UTE bicomponent analysis. Long T2* components are affected more by long T2 saturation and IR pulses, and short T2* components are affected more by fat saturation pulses.
Sensing HIV
Authors: Pickersgill Helen
Published: January 2014

The intracellular sensor that triggers the death of human lymphoid CD4 T cells abortively infected with HIV is identified.
The Sugar-Cancer Connection in 3D
Authors: Ferrarelli Leslie K.
Published: January 2014

A three-dimensional culture model shows that increased glycolysis can initiate and maintain malignant phenotypes.
Gender-Specific Differences in Hematopoeisis
Authors: Gough Nancy R.
Published: January 2014

In female mice, estrogen stimulates hematopoietic stem cell division.
Life or Death Decisions
Authors: Wong Wei
Published: January 2014

The abundance of a phosphatase that targets a death receptor determines whether autophagy protects cells against apoptosis.
Evaluation of Acanthamoeba Myosin-IC as a Potential Therapeutic Target
Authors: Martín-Navarro Carmen M. , Lorenzo-Morales Jacob , López-Arencibia Atteneri , Reyes-Batlle María , Piñero José E. , Valladares Basilio , Maciver Sutherland K.
Published: January 2014

Members of the genus
Acanthamoeba
are facultative pathogens of humans, causing a sight-threatening keratitis and a fatal encephalitis. We have targeted myosin-IC by using small interfering RNA (siRNA) silencing as a therapeutic approach, since it is known that the function of this protein is vital for the amoeba. In this work, specific siRNAs against the
Acanthamoeba
myosin-IC gene were developed. Treated and control amoebae were cultured in growth and encystment media to evaluate the induced effects after myosin-IC gene knockdown, as we have anticipated that cyst formation may be impaired. The effects of myosin-IC gene silencing were inhibition of cyst formation, inhibition of completion of cytokinesis, inhibition of osmoregulation under osmotic stress conditions, and death of the amoebae. The finding that myosin-IC silencing caused incompletion of cytokinesis is in agreement with earlier suggestions that the protein plays a role in cell locomotion, which is necessary to pull daughter cells apart after mitosis in a process known as “traction-mediated cytokinesis”. We conclude that myosin-IC is a very promising potential drug target for the development of much-needed antiamoebal drugs and that it should be further exploited for
Acanthamoeba
therapy.
Strategy for Rapid Detection of Carbapenemase-Producing Enterobacteriaceae
Authors: Dortet Laurent , Bréchard Ludivine , Cuzon Gaëlle , Poirel Laurent , Nordmann Patrice
Published: January 2014

A prospective survey was conducted on 862
Enterobacteriaceae
isolates with reduced susceptibility to carbapenems. The Carba NP test, UV spectrophotometry, and a DNA microarray were used to detect carbapenemase producers, and the results were compared to those from PCR and sequencing. The 172 carbapenemase producers were detected using the Carba NP test and UV spectrophotometry, whereas the DNA microarray failed to detect IMI producers. The use of the Carba NP test as a first screening, followed by the use of molecular techniques, has been determined to be an efficient strategy for identifying carbapenemase-producing
Enterobacteriaceae
.
Alkyl Galactofuranosides Strongly Interact with Leishmania donovani Membrane and Provide Antileishmanial Activity
Authors: Suleman Muhammad , Gangneux Jean-Pierre , Legentil Laurent , Belaz Sorya , Cabezas Yari , Manuel Christelle , Dureau Rémy , Sergent Odile , Burel Agnès , Daligault Franck , Ferrières Vincent , Robert-Gangneux Florence
Published: January 2014

We investigated the
in vitro
effects of four alkyl-galactofuranoside derivatives, i.e., octyl-β-
d
-galactofuranoside (compound 1), 6-amino-β-
d
-galactofuranoside (compound 2), 6-
N
-acetamido-β-
d
-galactofuranoside (compound 3), and 6-azido-β-
d
-galactofuranoside (compound 4), on
Leishmania donovani
. Their mechanism of action was explored using electron paramagnetic resonance spectroscopy (EPR) and nuclear magnetic resonance (NMR), and ultrastructural alterations were analyzed by transmission electron microscopy (TEM). Compound 1 showed the most promising effects by inhibiting promastigote growth at a 50% inhibitory concentration (IC
50
) of 8.96 ± 2.5 μM. All compounds exhibit low toxicity toward human macrophages. Compound 1 had a higher selectivity index than the molecule used for comparison, i.e., miltefosine (159.7 versus 37.9, respectively). EPR showed that compound 1 significantly reduced membrane fluidity compared to control promastigotes and to compound 3. The furanose ring was shown to support this effect, since the isomer galactopyranose had no effect on parasite membrane fluidity or growth. NMR showed a direct interaction of all compounds (greatest with compound 1, followed by compounds 2, 3, and 4, in descending order) with the promastigote membrane and with octyl-galactopyranose and octanol, providing evidence that the
n
-octyl chain was primarily involved in anchoring with the parasite membrane, followed by the putative crucial role of the furanose ring in the antileishmanial activity. A morphological analysis of compound 1-treated promastigotes by TEM revealed profound alterations in the parasite membrane and organelles, but this was not the case with compound 3. Quantification of annexin V binding by flow cytometry confirmed that compound 1 induced apoptosis in >90% of promastigotes. The effect of compound 1 was also assessed on intramacrophagic amastigotes and showed a reduction in amastigote growth associated with an increase of reactive oxygen species (ROS) production, thus validating its promising effect.
Community-Onset Escherichia coli Infection Resistant to Expanded-Spectrum Cephalosporins in Low-Prevalence Countries
Authors: Rogers Benjamin A. , Ingram Paul R. , Runnegar Naomi , Pitman Matthew C. , Freeman Joshua T. , Athan Eugene , Havers Sally M. , Sidjabat Hanna E. , Jones Mark , Gunning Earleen , De Almeida Mary , Styles Kaylene , Paterson David L.
Published: January 2014

By global standards, the prevalence of community-onset expanded-spectrum-cephalosporin-resistant (ESC-R)
Escherichia coli
remains low in Australia and New Zealand. Of concern, our countries are in a unique position, with high extramural resistance pressure from close population and trade links to Asia-Pacific neighbors with high ESC-R
E. coli
rates. We aimed to characterize the risks and dynamics of community-onset ESC-R
E. coli
infection in our low-prevalence region. A case-control methodology was used. Patients with ESC-R
E. coli
or ESC-susceptible
E. coli
isolated from blood or urine were recruited at six geographically dispersed tertiary care hospitals in Australia and New Zealand. Epidemiological data were prospectively collected, and bacteria were retained for analysis. In total, 182 patients (91 cases and 91 controls) were recruited. Multivariate logistic regression identified risk factors for ESC-R among
E. coli
strains, including birth on the Indian subcontinent (odds ratio [OR] = 11.13, 95% confidence interval [95% CI] = 2.17 to 56.98,
P
= 0.003), urinary tract infection in the past year (per-infection OR = 1.430, 95% CI = 1.13 to 1.82,
P
= 0.003), travel to southeast Asia, China, the Indian subcontinent, Africa, and the Middle East (OR = 3.089, 95% CI = 1.29 to 7.38,
P
= 0.011), prior exposure to trimethoprim with or without sulfamethoxazole and with or without an expanded-spectrum cephalosporin (OR = 3.665, 95% CI = 1.30 to 10.35,
P
= 0.014), and health care exposure in the previous 6 months (OR = 3.16, 95% CI = 1.54 to 6.46,
P
= 0.02). Among our ESC-R
E. coli
strains, the
bla
CTX-M
ESBLs were dominant (83% of ESC-R
E. coli
strains), and the worldwide pandemic ST-131 clone was frequent (45% of ESC-R
E. coli
strains). In our low-prevalence setting, ESC-R among community-onset
E. coli
strains may be associated with both “export” from health care facilities into the community and direct “import” into the community from high-prevalence regions.
Ultradeep Sequencing Study of Chronic Hepatitis C Virus Genotype 1 Infection in Patients Treated with Daclatasvir, Peginterferon, and Ribavirin
Authors: Murakami Eisuke , Imamura Michio , Hayes C. Nelson , Abe Hiromi , Hiraga Nobuhiko , Honda Yoji , Ono Atsushi , Kosaka Keiichi , Kawaoka Tomokazu , Tsuge Masataka , Aikata Hiroshi , Takahashi Shoichi , Miki Daiki , Ochi Hidenori , Matsui Hirotaka , Kanai Akinori , Inaba Toshiya , McPhee Fiona , Chayama Kazuaki
Published: January 2014

Direct-acting antivirals (DAAs) are either part of the current standard of care or are in advanced clinical development for the treatment of patients chronically infected with hepatitis C virus (HCV) genotype 1, but concern exists with respect to the patients who fail these regimens with emergent drug-resistant variants. In the present study, ultradeep sequencing was performed to analyze resistance to daclatasvir (DCV), which is a highly selective nonstructural protein 5A (NS5A) inhibitor. Eight patients with HCV genotype 1b, who were either treatment naive or prior nonresponders to pegylated interferon plus ribavirin (Rebetol; Schering-Plough) (PEG-IFN/RBV) therapy, were treated with DCV combined with PEG-IFN alpha-2b (Pegintron; Schering-Plough, Kenilworth, NJ) and RBV. To identify the cause of viral breakthrough, the preexistence and emergence of DCV-resistant variants at NS5A amino acids were analyzed by ultradeep sequencing. Sustained virological response (SVR) was achieved in 6 of 8 patients (75%), with viral breakthrough occurring in the other 2 patients (25%). DCV-resistant variant Y93H preexisted as a minor population at higher frequencies (0.1% to 0.5%) in patients who achieved SVR. In patients with viral breakthrough, DCV-resistant variant mixtures emerged at NS5A-31 over time that persisted posttreatment with Y93H. Although enrichment of DCV-resistant variants was detected, the preexistence of a minor population of the variant did not appear to be associated with virologic response in patients treated with DCV/PEG-IFN/RBV. Ultradeep sequencing results shed light on the complexity of DCV-resistant quasispecies emerging over time, suggesting that multiple resistance pathways are possible within a patient who does not rapidly respond to a DCV-containing regimen. (This study has been registered at ClinicalTrials.gov under registration no. NCT01016912.)
Breakthrough Candidemia Due to Multidrug-Resistant Candida glabrata during Prophylaxis with a Low Dose of Micafungin
Authors: Bizerra Fernando César , Jimenez-Ortigosa Cristina , Souza Ana Carolina R. , Breda Giovanni Luis , Queiroz-Telles Flávio , Perlin David S. , Colombo Arnaldo L.
Published: January 2014

We identified a case of breakthrough candidemia in a 25-year-old patient receiving micafungin prophylaxis (50 mg/day). Five
Candida glabrata
isolates were obtained from blood cultures and were classified as multidrug-resistant isolates, since all of them exhibited high MICs for echinocandin and azole drugs. A mutation (S663F) in hot spot 1 of the
FKS
2 gene was found in all five isolates. This mutation yielded a 1,3-β-
d
-glucan synthase enzyme with highly reduced sensitivities to echinocandin drugs.
Class D β-Lactamases: Are They All Carbapenemases?
Authors: Antunes Nuno T. , Lamoureaux Toni L. , Toth Marta , Stewart Nichole K. , Frase Hilary , Vakulenko Sergei B.
Published: January 2014

Carbapenem-hydrolyzing class D β-lactamases (CHDLs) are enzymes of the utmost clinical importance due to their ability to produce resistance to carbapenems, the antibiotics of last resort for the treatment of various life-threatening infections. The vast majority of these enzymes have been identified in
Acinetobacter
spp., notably in
Acinetobacter baumannii
. The OXA-2 and OXA-10 enzymes predominantly occur in
Pseudomonas aeruginosa
and are currently classified as narrow-spectrum class D β-lactamases. Here we demonstrate that when OXA-2 and OXA-10 are expressed in
Escherichia coli
strain JM83, they produce a narrow-spectrum antibiotic resistance pattern. When the enzymes are expressed in
A. baumannii
ATCC 17978, however, they behave as extended-spectrum β-lactamases and confer resistance to carbapenem antibiotics. Kinetic studies of OXA-2 and OXA-10 with four carbapenems have demonstrated that their catalytic efficiencies with these antibiotics are in the same range as those of some recognized class D carbapenemases. These results are in disagreement with the classification of the OXA-2 and OXA-10 enzymes as narrow-spectrum β-lactamases, and they suggest that other class D enzymes that are currently regarded as noncarbapenemases may in fact be CHDLs.