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Acoustofluidic semen analysis for veterinary male bovine infertility assessment
- Jasmine O. Castro, Melati S. Abdul Halim, Lizebona A. Ambattu, Amgad R. Rezk, Ranganathan Prabhakar, Reza Nosrati, Leslie Y. Yeo
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- Journal:
- Flow: Applications of Fluid Mechanics / Volume 3 / 2023
- Published online by Cambridge University Press:
- 03 February 2023, E6
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We demonstrate through the use of a unique acoustically driven microfluidic extensional rheometry platform (ADMiER) that a single measurement – i.e. the time required for a liquid bridge filament comprising a microlitre semen sample to thin and break up under elastocapillary stresses – constitutes an appropriate proxy for quantifying the motile sperm concentration of the sample in place of computer-assisted sperm analysis (CASA) and haemocytometer measurements used in conventional semen assessment – without the need to separately resolve for individual dependencies on each sperm parameter. By benchmarking diagnostic test accuracy results of blind random bull semen samples ($n=35$) against OpenCASA measurements of these parameters, ADMiER is capable of predicting sperm quality to 93.7 % accuracy, 91.4 % sensitivity and 97.5 % specificity, with respect to commonly adopted veterinary industry minimum values for fertility. These results therefore highlight the potential diagnostic capability of the platform as a conceptual first step towards the development of a rapid, low-cost and portable alternative for veterinary male bovine fertility assessment.
C.5 Musashi-1 is a master regulator of aberrant translation in MYC-amplified Group 3 medulloblastoma
- MM Kameda-Smith, H Zhu, E Luo, C Venugopal, K Brown, BA Yee, S Xing, F Tan, D Bakhshinyan, AA Adile, M Subapanditha, D Picard, J Moffat, A Fleming, K Hope, J Provias, M Remke, Y Lu, J Reimand, R Wechsler-Reya, G Yeo, SK Singh
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- Journal:
- Canadian Journal of Neurological Sciences / Volume 48 / Issue s3 / November 2021
- Published online by Cambridge University Press:
- 05 January 2022, p. S19
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Background: Medulloblastoma (MB) is the most common solid malignant pediatric brain neoplasm. Group 3 (G3) MB, particularly MYC amplified G3 MB, is the most aggressive subgroup with the highest frequency of children presenting with metastatic disease, and is associated with a poor prognosis. To further our understanding of the role of MSI1 in MYC amplified G3 MB, we performed an unbiased integrative analysis of eCLIP binding sites, with changes observed at the transcriptome, the translatome, and the proteome after shMSI1 inhibition. Methods: Primary human pediatric MBs, SU_MB002 and HD-MB03 were kind gifts from Dr. Yoon-Jae Cho (Harvard, MS) and Dr. Till Milde (Heidelberg) and cultured for in vitro and in vivo experiments. eCLIP, RNA-seq, Polysome-seq, and TMT-MS were completed as previously described. Results:MSI1 is overexpressed in G3 MB. shRNA Msi1 interference resulted in a reduction in tumour burden conferring a survival advantage to mice injected with shMSI1 G3MB cells. Robust ranked multiomic analysis (RRA) identified an unconventional gene set directly perturbed by MSI1 in G3 MB. Conclusions: Our robust unbiased integrative analysis revealed a distinct role for MSI1 in the maintenance of the stem cell state in G3 MB through post-transcriptional modification of multiple pathways including identification of unconventional targets such as HIPK1.
31 Intracranial growing teratoma syndrome (IGTS): An international retrospective study
- George Michaiel, Douglas Strother, Nicholas Gottardo, Ute Bartels, Hallie Coltin, David D. Eisenstat, Juliette Hukin, Donna L. Johnston, Beverly Wilson, Shayna Zelcer, Jordan R. Hansford, Olivia Wells, Mohamed S. AbdelBaki, Mohammad H. Abu-Arja, Kristina A. Cole, Girish Dhall, Paul G. Fisher, Lindsey Hoffman, Sarah E.S. Leary, Emily E. Owens Pickle, Natasha P. Smiley, Amy Smith, Anna Vinitsky, Nicholas A. Vitanza, Avery Wright, Kee K. Yeo, Lionel M.L. Chow, Maria Kirby, Santosh Valvi, Magimairajan I. Vanan, Grace Wong, David Ziegler, Eric Bouffet, Lucie Lafay-Cousi
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- Canadian Journal of Neurological Sciences / Volume 45 / Issue S3 / June 2018
- Published online by Cambridge University Press:
- 27 July 2018, p. S13
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BACKGROUND: IGTS is a rare phenomenon of paradoxical germ cell tumor (GCT) growth during or following treatment despite normalization of tumor markers. We sought to evaluate the frequency, clinical characteristics and outcome of IGTS in patients in 21 North-American and Australian institutions. METHODS: Patients with IGTS diagnosed from 2000-2017 were retrospectively evaluated. RESULTS: Out of 739 GCT diagnoses, IGTS was identified in 33 patients (4.5%). IGTS occurred in 9/191 (4.7%) mixed-malignant GCTs, 4/22 (18.2%) immature teratomas (ITs), 3/472 (0.6%) germinomas/germinomas with mature teratoma, and in 17 secreting non-biopsied tumours. Median age at GCT diagnosis was 10.9 years (range 1.8-19.4). Male gender (84%) and pineal location (88%) predominated. Of 27 patients with elevated markers, median serum AFP and Beta-HCG were 70 ng/mL (range 9.2-932) and 44 IU/L (range 4.2-493), respectively. IGTS occurred at a median time of 2 months (range 0.5-32) from diagnosis, during chemotherapy in 85%, radiation in 3%, and after treatment completion in 12%. Surgical resection was attempted in all, leading to gross total resection in 76%. Most patients (79%) resumed GCT chemotherapy/radiation after surgery. At a median follow-up of 5.3 years (range 0.3-12), all but 2 patients are alive (1 succumbed to progressive disease, 1 to malignant transformation of GCT). CONCLUSION: IGTS occurred in less than 5% of patients with GCT and most commonly after initiation of chemotherapy. IGTS was more common in patients with IT-only on biopsy than with mixed-malignant GCT. Surgical resection is a principal treatment modality. Survival outcomes for patients who developed IGTS are favourable.
Life History and Ecology of Dwarf Spikerush (Eleocharis coloradoensis)
- Richard R. Yeo
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- Journal:
- Weed Science / Volume 28 / Issue 3 / May 1980
- Published online by Cambridge University Press:
- 12 June 2017, pp. 263-272
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Dwarf spikerush [Eleocharis coloradoensis (Britt.) Gilly], a perennial aquatic plant, is composed of many individual rosettes connected by rhizomes. Each rosette has needlelike culms attached to a stalk, a crown with an apical meristem, and many fibrous roots. It reproduces by achenes, subterranean tubers, and crown tubers. Dwarf spikerush achenes were harvested three times in 1 yr after the water level had been manipulated to promote flowering. The annual yield of achenes following this treatment was 79 kg per ha. Subterranean tubers began to form in September and formation was maximum in October. Individual plants grown for 1 yr developed an average of 351 tubers. Maximum density of tubers formed in hydrosoil was 7 per cm2. Longevity studies showed that the percentage germination of achenes and tubers decreased, respectively, from 48 to 32% and from 100 to 46% when stored wet at 4 C for 4 yr. Plants grown for 6 months from a single subterranean tuber, rosette, or achene spanned 150, 127, and 99 cm, respectively. The species thrived in a wide range of water qualities and on soft hydrosoils largely made up of silt, clay, and organic matter. On plants immersed in 0 to 100% sea water for 1 month, culms were injured in 30% sea water and killed in 40% sea water. Surviving plants showed some new growth after transfer to fresh water. Some tubers were incubated in diluted sea water. They germinated in solutions up to 80% sea water. Plants grown in water under different light intensities grew best at the maximum of 3,900 lux. More rosettes, culms, and inflorescences were produced with a 14-h photoperiod than 11- or 17-h photoperiod. Dwarf spikerush displaced other species by invading them when growth of the other plants was suppressed. The erect crowded culms of dwarf spikerush mechanically resisted incursion of other aquatic plants.
Morphological Development and Germination of Dwarf Spikerush (Eleocharis coloradoensis)
- Richard R. Yeo
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- Journal:
- Weed Science / Volume 27 / Issue 4 / July 1979
- Published online by Cambridge University Press:
- 12 June 2017, pp. 380-385
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Dwarf spikerush [Eleocharis coloradoensis (Britt.) Gilly] is an aquatic plant that will displace waterweeds. It was studied to obtain information that will help to manage unwanted vegetation in natural aquatic situations. The morphology of seed and tubers was examined at the light- and scanning-electron microscope levels. Inflorescences were found to bear 3 to 12 florets that matured acropetally. The pericarp was made up largely of rows of annulated cells covered with a water-soluble, waxlike substance that leached away when stored in water at 4 to 6 C. The seed coat consisted of three layers. Each layer contained lipids, giving evidence that they were composed of cutin. When the seed germinated, the cotyledonary sheath emerged first, followed by the culms. Tubers formed and matured in about 30 days. The shoot apices of tubers each had two buds that were protected by five to seven overlapping membraneous leaf scales. When tubers sprouted the longest bud grew first. The second bud contained the culm meristem.
Diquat and Copper-ion Residues in Salmon-spawning Channel
- R. R. Yeo, N. Dechoretz
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- Journal:
- Weed Science / Volume 24 / Issue 4 / July 1976
- Published online by Cambridge University Press:
- 12 June 2017, pp. 405-409
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A mixture of diquat [6,7-dihydrodipyrido(1,2-α: 2′,1′-c) pyrazinediium ion] and copper sulfate pentahydrate was applied to artificial chinook salmon (Onchorhynchus tshawytscha Wal.) spawning channels to reduce excessive growths of algae [Cladophora glomerata (L.) Kutz]. Juvenile salmon were not harmed by the applications. A concentration of 100 ppb w/w diquat plus 150 ppb copper-ion was maintained for 3 hr. The alga was controlled satisfactorily for distances up to 0.5 km per treatment. Each treatment consisted of one to three applications, each made on consecutive days. Water temperature was 11.2 C during three winter applications and 15.5 C during a spring application. Diquat was rapidly sorbed out of the treated water to 3.8 ppb at 1.6 km. Copper-ion residues dissipated to 60 ppb at 1.6 km.
Germination of Seed of Dwarf Spikerush (Eleocharis coloradoensis)
- R. R. Yeo, R. J. Dow
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- Journal:
- Weed Science / Volume 26 / Issue 5 / September 1978
- Published online by Cambridge University Press:
- 12 June 2017, pp. 425-431
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Treatments that enhanced the germination of dormant seed of dwarf spikerush [Eleocharis coloradoensis (Britt.) Gilly] the most were chilling seed at 2 C for 3 months and then scarifying with sodium hypochlorite, scarifying seed and then chilling wet seed at 7 C for 3 months, or chilling wet seed at 2 C for 24 months. Percentage of germination for these treatments were 58, 56, and 65%, respectively. Scarifying seed with sodium hypochlorite after they had been chilled wet for 12 to 24 months at 2 C reduced germination. Other treatments that significantly enhanced germination were chilling seed wet for 4 months at 2 C, scarifying dry-stored seed with a 5.25% solution of sodium hypochlorite for 10 h, and soaking seed in concentrated hydrochloric acid for 24 min. These latter treatments resulted in germination percentages of 35, 33, and 35, respectively. Eighty percent of the viable seed usually germinated within 10 days, and when germination was poor, seed lacked embryos or were empty. Dormancy appeared to be due to an impermeable seed coat and not to a germination inhibitor.
Dissipation of Endothall and Effects on Aquatic Weeds and Fish
- R. R. Yeo
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- Journal:
- Weed Science / Volume 18 / Issue 2 / March 1970
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- 12 June 2017, pp. 282-284
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Rates of dissipation, control of troublesome aquatic weeds, and toxicity to fish by the disodium and dipotassium salts of 7-oxabicyclo(2,2,1)-heptane-2,3-dicarboxylic acid (endothall) in farm reservoirs and in growth pools were studied from 1964 to 1967. In 4 out of 14 reservoir applications, initial concentrations of 0.3 to 1.4 ppm dissipated to near the limit of detection in 8 to 20 days. In the other 10, the dissipation ranged from 23 to an increase of 160% in 12 days. The average dissipation was 71%. In growth pools, initial concentrations of 0.5 to 4.0 ppm of endothal dissipated to 0.26 to 2.5 ppm in 12 days.
Survival of Seed and Tubers of Dwarf Spikerush (Eleocharis coloradoensis) After Exposure to Extreme Temperatures
- Richard R. Yeo, Jon R. Thurston
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- Journal:
- Weed Science / Volume 27 / Issue 4 / July 1979
- Published online by Cambridge University Press:
- 12 June 2017, pp. 434-436
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Seed and tubers and dwarf spikerush [Eleocharis coloradoensis (Britt.) Gilly] survived extremely cold and hot temperatures if damp-dried before exposure. Damp-dried seed survived 14 days exposure to −196 C and 21 days exposure to 72 C, and then germinated 59 and 24%, respectively. Seed submersed in water germinated 20% when exposed to −15 C for 30 days and 4% when exposed to 60 C for 3 days. When damp-dried seed were warmed at 37 C for 21 days the germination was nearly twice that for wet seed treated similarly. Tubers that were damp-dried before exposure survived −196 C for 14 days and 49 C for 21 days and then germinated 20 and 49%, respectively. Tubers that were exposed wet to hot or cold temperatures were killed at less extreme temperatures than seed. None of the tubers exposed wet survivied −15 C for 30 days or 49 C for 3 days.
Graph Metrics of Structural Brain Networks in Individuals with Schizophrenia and Healthy Controls: Group Differences, Relationships with Intelligence, and Genetics
- Ronald A. Yeo, Sephira G. Ryman, Martijn P. van den Heuvel, Marcel A. de Reus, Rex E. Jung, Jessica Pommy, Andrew R. Mayer, Stefan Ehrlich, S. Charles Schulz, Eric M. Morrow, Dara Manoach, Beng-Choon Ho, Scott R. Sponheim, Vince D. Calhoun
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- Journal:
- Journal of the International Neuropsychological Society / Volume 22 / Issue 2 / February 2016
- Published online by Cambridge University Press:
- 18 February 2016, pp. 240-249
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Objectives: One of the most prominent features of schizophrenia is relatively lower general cognitive ability (GCA). An emerging approach to understanding the roots of variation in GCA relies on network properties of the brain. In this multi-center study, we determined global characteristics of brain networks using graph theory and related these to GCA in healthy controls and individuals with schizophrenia. Methods: Participants (N=116 controls, 80 patients with schizophrenia) were recruited from four sites. GCA was represented by the first principal component of a large battery of neurocognitive tests. Graph metrics were derived from diffusion-weighted imaging. Results: The global metrics of longer characteristic path length and reduced overall connectivity predicted lower GCA across groups, and group differences were noted for both variables. Measures of clustering, efficiency, and modularity did not differ across groups or predict GCA. Follow-up analyses investigated three topological types of connectivity—connections among high degree “rich club” nodes, “feeder” connections to these rich club nodes, and “local” connections not involving the rich club. Rich club and local connectivity predicted performance across groups. In a subsample (N=101 controls, 56 patients), a genetic measure reflecting mutation load, based on rare copy number deletions, was associated with longer characteristic path length. Conclusions: Results highlight the importance of characteristic path lengths and rich club connectivity for GCA and provide no evidence for group differences in the relationships between graph metrics and GCA. (JINS, 2016, 22, 240–249)
Contributors
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- By Arthur S. Abramson, Norhaida Aman, Virginie Attina, Sapna Bhat, B. Bhuvaneshwari, Denis Burnham, Brian Byrne, Hsin-Chin Chen, Shyamala K. Chengappa, Chris Davis, Jackson T. Gandour, Winston D. Goh, Thom Huebner, Lixian Jin, Jing Zhou, R. Malatesha Joshi, Benjawan Kasisopa, Jeesun Kim, Christine Kitamura, Ananthanarayan Krishnan, Lay Wah Lee, Elena Lieven, Sudaporn Luksaneeyanawin, Ramesh Mishra, Sonali Nag, Vishnu K. K. Nair, Loraine K. Obler, Tomasina Oh, Richard K. Olson, Prakash Padakannaya, Aparna Pandey, Avanthi Niranjan Paplikar, Shalmalee Pitale, Chaitra Rao, Theeraporn Ratitamkul, Nan Xu Rattanasone, Sunil Kumar Ravi, Rogayah A. Razak, Ronan Reilly, Susan Rickard Liow, Khazriyati Salehuddin, Stefan Samuelsson, Vaijayanthi M. Sarma, Yasuhiro Shirai, Shruti Sircar, John Song, Sabine Stoll, Lidia Suárez, Jennie Tran, Jie-Li Tsai, Kimiko Tsukada, Jyotsna Vaid, Heather Winskel, Janet Wright, Kelly Yeo
- Edited by Heather Winskel, Southern Cross University, Australia, Prakash Padakannaya, University of Mysore, India
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- South and Southeast Asian Psycholinguistics
- Published online:
- 05 December 2013
- Print publication:
- 28 November 2013, pp xvii-xx
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The impact of parent socio-economic status on executive functioning and cortical morphology in individuals with schizophrenia and healthy controls
- R. A. Yeo, D. Martinez, J. Pommy, S. Ehrlich, S. C. Schulz, B.-C. Ho, J. R. Bustillo, V. D. Calhoun
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- Journal:
- Psychological Medicine / Volume 44 / Issue 6 / April 2014
- Published online by Cambridge University Press:
- 19 July 2013, pp. 1257-1265
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Background
Relatively lower executive functioning is characteristic of individuals with schizophrenia. As low socio-economic status (SES) early in life (i.e. parent SES) has been linked with lower executive skills in healthy children, we hypothesized that parental SES (pSES) would be more strongly related to executive functioning in individuals with schizophrenia than in controls and have a greater impact on prefrontal cortical morphology.
MethodHealthy controls (n = 125) and individuals with schizophrenia (n = 102) completed tests assessing executive functioning and intelligence. The groups were matched on pSES, which was evaluated with the Hollingshead–Redlich scale. A principal components analysis (PCA) was conducted on 10 variables from six executive tests, yielding three specific components (fluency, planning and response inhibition). Voxel-based morphometry (VBM) was used to evaluate effects of pSES on gray matter (GM) concentration.
ResultsLower pSES was associated with lower scores across the three executive functioning components, and a significant group by pSES interaction was observed such that low pSES, in particular, affected individuals with schizophrenia. These effects remained significant when intellectual ability, education and self-SES (sSES) were added as covariates. VBM revealed that lower pSES was associated with reduced GM volume in several anterior brain regions, especially the superior frontal gyrus, in patients but not in controls.
ConclusionsThese findings suggest that individuals with schizophrenia may be particularly vulnerable to the adverse impact of low pSES, in terms of both lower executive skills and reduced anterior GM volumes.
Using genetic, cognitive and multi-modal neuroimaging data to identify ultra-high-risk and first-episode psychosis at the individual level
- W. Pettersson-Yeo, S. Benetti, A. F. Marquand, F. Dell‘Acqua, S. C. R. Williams, P. Allen, D. Prata, P. McGuire, A. Mechelli
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- Journal:
- Psychological Medicine / Volume 43 / Issue 12 / December 2013
- Published online by Cambridge University Press:
- 14 March 2013, pp. 2547-2562
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Background
Group-level results suggest that relative to healthy controls (HCs), ultra-high-risk (UHR) and first-episode psychosis (FEP) subjects show alterations in neuroanatomy, neurofunction and cognition that may be mediated genetically. It is unclear, however, whether these groups can be differentiated at single-subject level, for instance using the machine learning analysis support vector machine (SVM). Here, we used a multimodal approach to examine the ability of structural magnetic resonance imaging (sMRI), functional MRI (fMRI), diffusion tensor neuroimaging (DTI), genetic and cognitive data to differentiate between UHR, FEP and HC subjects at the single-subject level using SVM.
MethodThree age- and gender-matched SVM paired comparison groups were created comprising 19, 19 and 15 subject pairs for FEP versus HC, UHR versus HC and FEP versus UHR, respectively. Genetic, sMRI, DTI, fMRI and cognitive data were obtained for each participant and the ability of each to discriminate subjects at the individual level in conjunction with SVM was tested.
ResultsSuccessful classification accuracies (p < 0.05) comprised FEP versus HC (genotype, 67.86%; DTI, 65.79%; fMRI, 65.79% and 68.42%; cognitive data, 73.69%), UHR versus HC (sMRI, 68.42%; DTI, 65.79%), and FEP versus UHR (sMRI, 76.67%; fMRI, 73.33%; cognitive data, 66.67%).
ConclusionsThe results suggest that FEP subjects are identifiable at the individual level using a range of biological and cognitive measures. Comparatively, only sMRI and DTI allowed discrimination of UHR from HC subjects. For the first time FEP and UHR subjects have been shown to be directly differentiable at the single-subject level using cognitive, sMRI and fMRI data. Preliminarily, the results support clinical development of SVM to help inform identification of FEP and UHR subjects, though future work is needed to provide enhanced levels of accuracy.
The appearance of boundary layers and drift flows due to high-frequency surface waves
- Ofer Manor, Leslie Y. Yeo, James R. Friend
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- Journal:
- Journal of Fluid Mechanics / Volume 707 / 25 September 2012
- Published online by Cambridge University Press:
- 20 July 2012, pp. 482-495
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The classical Schlichting boundary layer theory is extended to account for the excitation of generalized surface waves in the frequency and velocity amplitude range commonly used in microfluidic applications, including Rayleigh and Sezawa surface waves and Lamb, flexural and surface-skimming bulk waves. These waves possess longitudinal and transverse displacements of similar magnitude along the boundary, often spatiotemporally out of phase, giving rise to a periodic flow shown to consist of a superposition of classical Schlichting streaming and uniaxial flow that have no net influence on the flow over a long period of time. Correcting the velocity field for weak but significant inertial effects results in a non-vanishing steady component, a drift flow, itself sensitive to both the amplitude and phase (prograde or retrograde) of the surface acoustic wave propagating along the boundary. We validate the proposed theory with experimental observations of colloidal pattern assembly in microchannels filled with dilute particle suspensions to show the complexity of the boundary layer, and suggest an asymptotic slip boundary condition for bulk flow in microfluidic applications that are actuated by surface waves.
Nano Superlattice-like Materials as Thermal Insulators for Phase-Change Random Access Memory
- D. Loke, L. P. Shi, W. J. Wang, R. Zhao, L. T. Ng, K. G. Lim, H. X. Yang, T. C. Chong, Y. C. Yeo.
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- Journal:
- MRS Online Proceedings Library Archive / Volume 1404 / 2012
- Published online by Cambridge University Press:
- 16 March 2012, mrsf11-1404-w09-05
- Print publication:
- 2012
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Nanoscale superlattice-like (SLL) dielectric was employed to reduce the power consumption of the Phase-change random access memory (PCRAM) cells. In this study, we have simulated and found that the cells with the SLL dielectric have a higher peak temperature compared to that of the cells with the SiO2 dielectric after constant pulse activation, due to the interface scattering mechanism. Scaling of the SLL dielectric has resulted in higher peak temperatures, which can be even higher after material/structural modifications. Furthermore, the SLL dielectric has good material properties that enable the cells to have high endurance. This shows the effectiveness of the SLL dielectric for advanced memory applications.
Numerical simulations of concentrated suspensions of monodisperse particles in a Poiseuille flow
- KYONGMIN YEO, MARTIN R. MAXEY
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- Journal:
- Journal of Fluid Mechanics / Volume 682 / 10 September 2011
- Published online by Cambridge University Press:
- 03 August 2011, pp. 491-518
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The dynamics of concentrated suspensions of non-colloidal, monodisperse particles in plane Poiseuille flows are investigated by fully three-dimensional numerical simulations for bulk volume fractions of 0.20–0.40 of neutrally-buoyant particles. The ensemble averages of the volume fraction and particle velocity profiles are consistent with previous experiments. A statistical analysis indicates that there is an intermediate region between particle layers near the wall and a plug region in the core, in which the behaviour of ensemble-averaged suspension field can be approximated by a continuum theory. In the intermediate region, the wall-normal and spanwise velocity fluctuations, angular velocity in the vorticity direction and particle shear stress are found to be linear functions of the distance from the wall. The particle normal stresses in the intermediate region are almost uniform, consistent with the concept of normal-stress-driven particle migration. The intermediate region decreases in extent and the width of the core region increases for larger bulk volume fractions. There is a remarkable similarity between the particle–phase pressure profiles scaled by the local shear rate for different bulk volume fractions. The particle pressure profiles in the intermediate region are compared with the rheological model proposed by Morris & Boulay (1999). The effective viscosity, evaluated from the ratio of the total shear stress to the fluid-phase shear stress, shows a good agreement with empirical viscosity relations in Couette-flow suspensions. In the present study, both non-local dynamics and finite-size effects of the particles are evident in the core of the channel. These effects are more pronounced at larger volume fractions.
Contributors
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- By Rose Teteki Abbey, K. C. Abraham, David Tuesday Adamo, LeRoy H. Aden, Efrain Agosto, Victor Aguilan, Gillian T. W. Ahlgren, Charanjit Kaur AjitSingh, Dorothy B E A Akoto, Giuseppe Alberigo, Daniel E. Albrecht, Ruth Albrecht, Daniel O. Aleshire, Urs Altermatt, Anand Amaladass, Michael Amaladoss, James N. Amanze, Lesley G. Anderson, Thomas C. Anderson, Victor Anderson, Hope S. Antone, María Pilar Aquino, Paula Arai, Victorio Araya Guillén, S. Wesley Ariarajah, Ellen T. Armour, Brett Gregory Armstrong, Atsuhiro Asano, Naim Stifan Ateek, Mahmoud Ayoub, John Alembillah Azumah, Mercedes L. García Bachmann, Irena Backus, J. Wayne Baker, Mieke Bal, Lewis V. Baldwin, William Barbieri, António Barbosa da Silva, David Basinger, Bolaji Olukemi Bateye, Oswald Bayer, Daniel H. Bays, Rosalie Beck, Nancy Elizabeth Bedford, Guy-Thomas Bedouelle, Chorbishop Seely Beggiani, Wolfgang Behringer, Christopher M. Bellitto, Byard Bennett, Harold V. Bennett, Teresa Berger, Miguel A. Bernad, Henley Bernard, Alan E. Bernstein, Jon L. Berquist, Johannes Beutler, Ana María Bidegain, Matthew P. Binkewicz, Jennifer Bird, Joseph Blenkinsopp, Dmytro Bondarenko, Paulo Bonfatti, Riet en Pim Bons-Storm, Jessica A. Boon, Marcus J. Borg, Mark Bosco, Peter C. Bouteneff, François Bovon, William D. Bowman, Paul S. Boyer, David Brakke, Richard E. Brantley, Marcus Braybrooke, Ian Breward, Ênio José da Costa Brito, Jewel Spears Brooker, Johannes Brosseder, Nicholas Canfield Read Brown, Robert F. Brown, Pamela K. Brubaker, Walter Brueggemann, Bishop Colin O. Buchanan, Stanley M. Burgess, Amy Nelson Burnett, J. Patout Burns, David B. Burrell, David Buttrick, James P. Byrd, Lavinia Byrne, Gerado Caetano, Marcos Caldas, Alkiviadis Calivas, William J. Callahan, Salvatore Calomino, Euan K. Cameron, William S. Campbell, Marcelo Ayres Camurça, Daniel F. Caner, Paul E. Capetz, Carlos F. Cardoza-Orlandi, Patrick W. Carey, Barbara Carvill, Hal Cauthron, Subhadra Mitra Channa, Mark D. Chapman, James H. Charlesworth, Kenneth R. Chase, Chen Zemin, Luciano Chianeque, Philip Chia Phin Yin, Francisca H. Chimhanda, Daniel Chiquete, John T. Chirban, Soobin Choi, Robert Choquette, Mita Choudhury, Gerald Christianson, John Chryssavgis, Sejong Chun, Esther Chung-Kim, Charles M. A. Clark, Elizabeth A. Clark, Sathianathan Clarke, Fred Cloud, John B. Cobb, W. Owen Cole, John A Coleman, John J. Collins, Sylvia Collins-Mayo, Paul K. Conkin, Beth A. Conklin, Sean Connolly, Demetrios J. Constantelos, Michael A. Conway, Paula M. Cooey, Austin Cooper, Michael L. Cooper-White, Pamela Cooper-White, L. William Countryman, Sérgio Coutinho, Pamela Couture, Shannon Craigo-Snell, James L. Crenshaw, David Crowner, Humberto Horacio Cucchetti, Lawrence S. Cunningham, Elizabeth Mason Currier, Emmanuel Cutrone, Mary L. Daniel, David D. Daniels, Robert Darden, Rolf Darge, Isaiah Dau, Jeffry C. Davis, Jane Dawson, Valentin Dedji, John W. de Gruchy, Paul DeHart, Wendy J. Deichmann Edwards, Miguel A. De La Torre, George E. Demacopoulos, Thomas de Mayo, Leah DeVun, Beatriz de Vasconcellos Dias, Dennis C. Dickerson, John M. Dillon, Luis Miguel Donatello, Igor Dorfmann-Lazarev, Susanna Drake, Jonathan A. Draper, N. Dreher Martin, Otto Dreydoppel, Angelyn Dries, A. J. Droge, Francis X. D'Sa, Marilyn Dunn, Nicole Wilkinson Duran, Rifaat Ebied, Mark J. Edwards, William H. Edwards, Leonard H. Ehrlich, Nancy L. Eiesland, Martin Elbel, J. Harold Ellens, Stephen Ellingson, Marvin M. Ellison, Robert Ellsberg, Jean Bethke Elshtain, Eldon Jay Epp, Peter C. Erb, Tassilo Erhardt, Maria Erling, Noel Leo Erskine, Gillian R. Evans, Virginia Fabella, Michael A. Fahey, Edward Farley, Margaret A. Farley, Wendy Farley, Robert Fastiggi, Seena Fazel, Duncan S. Ferguson, Helwar Figueroa, Paul Corby Finney, Kyriaki Karidoyanes FitzGerald, Thomas E. FitzGerald, John R. Fitzmier, Marie Therese Flanagan, Sabina Flanagan, Claude Flipo, Ronald B. 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Yee, Viktor Yelensky, Yeo Khiok-Khng, Gustav K. K. Yeung, Angela Yiu, Amos Yong, Yong Ting Jin, You Bin, Youhanna Nessim Youssef, Eliana Yunes, Robert Michael Zaller, Valarie H. Ziegler, Barbara Brown Zikmund, Joyce Ann Zimmerman, Aurora Zlotnik, Zhuo Xinping
- Edited by Daniel Patte, Vanderbilt University, Tennessee
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- The Cambridge Dictionary of Christianity
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- 05 August 2012
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- 20 September 2010, pp xi-xliv
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Dynamics of concentrated suspensions of non-colloidal particles in Couette flow
- KYONGMIN YEO, MARTIN R. MAXEY
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- Journal of Fluid Mechanics / Volume 649 / 25 April 2010
- Published online by Cambridge University Press:
- 13 April 2010, pp. 205-231
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Fully three-dimensional numerical simulations of concentrated suspensions of O(1000) particles in a Couette flow at zero Reynolds number are performed with the goal of determining the wall effects on concentrated suspensions of non-colloidal particles. The simulations, based on the force-coupling method, are performed for 0.2 ≤ φ ≤ 0.4 and 10 < Ly/a < 30, where φ denotes the volume fraction and Ly and a are, respectively, the channel height and the particle radius. It is shown that the suspensions can be divided into three regions depending on the microstructures; the wall region where a structured particle layering is dominant, the core region in which the suspension field is quasi-homogeneous, and the buffer region which shows the characteristics of both the particle layer and the shear structure. The width of the inhomogeneous region (wall and buffer) is a function of φ and not sensitive to Ly/a, once Ly/a is larger than a threshold. Rheological properties in the inhomogeneous and quasi-homogeneous regions are investigated. The particle stresses are compared with previous rheological models.
The molecular epidemiology and phylogeography of Trypanosoma cruzi and parallel research on Leishmania: looking back and to the future
- M. A. MILES, M. S. LLEWELLYN, M. D. LEWIS, M. YEO, R. BALEELA, S. FITZPATRICK, M. W. GAUNT, I. L. MAURICIO
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- Parasitology / Volume 136 / Issue 12 / October 2009
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- 20 August 2009, pp. 1509-1528
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Trypanosoma cruzi is the protozoan agent of Chagas disease, and the most important parasitic disease in Latin America. Protozoa of the genus Leishmania are global agents of visceral and cutaneous leishmaniasis, fatal and disfiguring diseases. In the 1970s multilocus enzyme electrophoresis demonstrated that T. cruzi is a heterogeneous complex. Six zymodemes were described, corresponding with currently recognized lineages, TcI and TcIIa-e – now defined by multiple genetic markers. Molecular epidemiology has substantially resolved the phylogeography and ecological niches of the T. cruzi lineages. Genetic hybridization has fundamentally influenced T. cruzi evolution and epidemiology of Chagas disease. Genetic exchange of T. cruzi in vitro involves fusion of diploids and genome erosion, producing aneuploid hybrids. Transgenic fluorescent clones are new tools to elucidate molecular genetics and phenotypic variation. We speculate that pericardial sequestration plays a role in pathogenesis. Multilocus sequence typing, microsatellites and, ultimately, comparative genomics are improving understanding of T. cruzi population genetics. Similarly, in Leishmania, genetic groups have been defined, including epidemiologically important hybrids; genetic exchange can occur in the sand fly vector. We describe the profound impact of this parallel research on genetic diversity of T. cruzi and Leishmania, in the context of epidemiology, taxonomy and disease control.
Aircraft applications of insecticides in East Africa: XII.—Preliminary attempts to reduce the cost of controlling the tsetse species Glossina morsitans Westw., G. swynnertoni Aust. and G. pallidipes Aust. in Savannah Woodland
- R. Foster, P. J. White, D. Yeo
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- Bulletin of Entomological Research / Volume 52 / Issue 2 / June 1961
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- 10 July 2009, pp. 293-303
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Following successful small-scale trials, an attempt was made, by aircraft application of insecticide, to eradicate Glossina morsitans Westw. and G. pallidipes Aust. from an isolated block of savannah woodland, approximately 11 sq. miles in extent, at Chungai in the Central Province of Tanganyika between July 1958 and January 1959. A single-engined aircraft, fitted with two belt-driven rotary-cage atomisers, was used to apply a 5 per cent, solution of γ BHC in power kerosene at a nominal dosage of 0·08 gal. per acre (0.04 lb. γ BHC per acre). Seven applications were made at approximately 28-day intervals, the time taken to complete an application varying from five to eight days. The operation failed to control the flies. Although each of the first two applications reduced the apparent density of G. morsitans by about 90 per cent, and that of G. pallidipes by a lesser, although still considerable, factor, later applications gave varying and often low mortalities, and the populations increased slowly for some time, the insecticide applications causing only temporary depressions in numbers. Numbers fell towards the end of the operation, but final reductions were only about 50 per cent, or less. Kills of female flies were low, and this undoubtedly led to the eventual failure.
The low volume-dosage, a drop spectrum that possibly contained too few droplets of the required size, meteorological conditions, and biological factors that apparently favoured the survival of female flies are suggested as contributory elements to the low mortalities.
Operational costs were considerably lower than in previous work.