1,448 results on '"R. Higgins"'
Search Results
202. 117: Performance of routine first trimester sonographic evaluation of fetal anatomy: results of the multicentre test rct
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Cecelia Mulcahy, Alison Hunter, Fionnuala Breathnach, Patrick Dicker, Fionnuala M. McAuliffe, Elizabeth Tully, Fiona Cody, John J. Morrison, Amanda Cotter, Peter McParland, John R. Higgins, Sean Daly, Fionnuala Mone, and Fergal D. Malone
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medicine.medical_specialty ,First trimester ,Fetal anatomy ,Randomized controlled trial ,Obstetrics ,law ,business.industry ,medicine ,Obstetrics and Gynecology ,business ,Test (assessment) ,Surgery ,law.invention - Published
- 2017
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203. 562: The effect of excessive gestational weight gain on mode of delivery and intrapartum complications
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Cecelia Mulcahy, Michael J. Turner, Fiona Cody, Fergal D. Malone, Ann McHugh, Fionnuala Breathnach, Naomi Burke, Gerard Burke, Amanda Cotter, Michael Geary, Peter McParland, Elizabeth Tully, Fionnuala M. McAuliffe, John R. Higgins, Sean Daly, John J. Morrison, Samina Dornan, and Pat Dicker
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medicine.medical_specialty ,Mode of delivery ,business.industry ,Obstetrics ,medicine ,Obstetrics and Gynecology ,Gestation ,medicine.symptom ,business ,Weight gain - Published
- 2017
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204. Evaluation and Verification of the Seeplex Diarrhea-V ACE Assay for Simultaneous Detection of Adenovirus, Rotavirus, and Norovirus Genogroups I and II in Clinical Stool Specimens
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Rachel R. Higgins, Melissa Beniprashad, Mark Cardona, Steven Masney, Jonathan B. Gubbay, and Donald E. Low
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Adult ,Male ,Rotavirus ,Microbiology (medical) ,Adolescent ,Genotype ,viruses ,medicine.disease_cause ,Sensitivity and Specificity ,Adenoviridae ,Astrovirus ,Microbiology ,Feces ,Young Adult ,fluids and secretions ,Virology ,Multiplex polymerase chain reaction ,medicine ,Humans ,Multiplex ,Child ,Aged ,Retrospective Studies ,Aged, 80 and over ,biology ,Reverse Transcriptase Polymerase Chain Reaction ,Norovirus ,Infant ,virus diseases ,Middle Aged ,biology.organism_classification ,Gastroenteritis ,Diarrhea ,Virus Diseases ,Child, Preschool ,Female ,medicine.symptom ,Adenovirus+Rotavirus ,Multiplex Polymerase Chain Reaction - Abstract
Acute viral gastroenteritis is an intestinal infection that can be caused by several different viruses. Here we describe the evaluation and verification of Seeplex Diarrhea-V ACE (Seeplex DV), a novel commercial multiplex reverse transcription-PCR (RT-PCR) assay that detects 5 diarrheal pathogens, including adenovirus, rotavirus, norovirus genogroup I (GI) and GII, and astrovirus. We describe a retrospective study of 200 clinical specimens of which 177 were stool specimens previously tested for the presence of gastrointestinal viruses by electron microscopy (EM) and/or real-time RT-PCR (rRT-PCR). The remaining 23 specimens comprised other human pathogens of viral or bacterial origin. Discordant norovirus GI and GII results were resolved using a commercial kit; discordant adenovirus and rotavirus results were resolved using a home brew multiplex rRT-PCR assay. Diagnostic sensitivities and specificities were calculated before and after discordant analysis. After discordant analysis, estimated diagnostic sensitivities were 100% for adenovirus, rotavirus, and norovirus GI and 97% for norovirus GII. Diagnostic specificities after discordant analysis were 100% for adenovirus, rotavirus, and norovirus GI and 99.4% for norovirus GII. The 95% limits of detection were 31, 10, 2, and 1 genome equivalent per reaction for adenovirus, rotavirus, and norovirus GI and GII, respectively. The results demonstrate that the Seeplex DV assay is sensitive, specific, convenient, and reliable for the simultaneous detection of several viral pathogens directly in specimens from patients with gastroenteritis. Importantly, this novel multiplex PCR assay enabled the identification of viral coinfections in 12 (6.8%) stool specimens.
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- 2011
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205. Standardized Characterization of a Flow Through Microbial Fuel Cell
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Shelley D. Minteer, Michael J. Cooney, Scott R. Higgins, Plamen Atanassov, and Carolin Lau
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Microbial fuel cell ,Data collection ,Stack (abstract data type) ,Computer science ,Continuous flow ,Flow (psychology) ,Electrochemistry ,Nanotechnology ,Biochemical engineering ,Cell design ,Engineering analysis ,Analytical Chemistry ,Characterization (materials science) - Abstract
Microbial fuel cell research is a relatively new and fast growing field of interdisciplinary effort that has drawn scientists from several disparate disciplines. Consequently, establishing a “common language” regarding the “means and ways” of experimental preparation, data collection and characterization to obtain accurate and comparable figures of merit (describing microbial fuel cell performance) has proven difficult. We present a methodology for comprehensive engineering analysis from inoculation through batch, fed-batch and finally continuous flow operation, and detail how a modified stack cell design complements this. More, our cell is able to operate near the thermodynamic maximum potential for oxidation of lactate.
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- 2011
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206. Hybrid Biofuel Cell: Microbial Fuel Cell with an Enzymatic Air-Breathing Cathode
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Carolin Lau, Scott R. Higgins, Michael J. Cooney, Shelley D. Minteer, and Plamen Atanassov
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Nanotube ,Microbial fuel cell ,Materials science ,biology ,Open-circuit voltage ,General Chemistry ,Direct-ethanol fuel cell ,biology.organism_classification ,Shewanella ,Catalysis ,Cathode ,law.invention ,Anode ,Chemical engineering ,law ,Polarization (electrochemistry) - Abstract
A hybrid lactate/air biofuel cell has been created using a microbial anode with Shewanella MR1 integrated into a chitosan–carbon nanotube porous matrix and a DET-based laccase air-breathing cathode. Open circuit potentials of 1 V and power densities of 26 W/m3 are reported. A stable 5-day galvanostatic polarization shows a loss of only 4% of potential.
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- 2011
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207. 22q13.32 Deletion and Duplication and Inversion in the Same Family: A Rare Occurrence
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Rodney R. Higgins, Farooqua Jafri, Raymond C. Tervo, and James M. Fink
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Genetics ,medicine.diagnostic_test ,business.industry ,Gene duplication ,Medicine ,Inversion (evolutionary biology) ,Chromosome ,Case Report ,Deletion syndrome ,Global developmental delay ,business ,Early infancy ,Genetic testing - Abstract
Chromosome 22q13.3 deletion syndrome is a well-recognized cause of global developmental delay, while duplication of the same chromosome is a rare occurrence. The presence of both abnormalities in the same family has never been reported, to our knowledge. We report a rare occurrence of 22q13.3 duplication and 22q13.3 deletion in siblings, as a consequence of a mother's inversion on her 22nd chromosome (p13;q13.32). A 6 year old male was noted in infancy to have mild global developmental delay without dysmorphic features. His genetic testing revealed he had 22q13.3 duplication to the terminus. His 4 year old brother was noted in early infancy to have severe global developmental delay and dysmorphic features related to 22q13.3 deletion to the terminus. Their mother had a long inversion on her 22nd chromosome. Genetic tests for their father and eldest brother were unremarkable. The mother's inversion may rearrange to form 22q duplication or deletion when passed on to children. The chance of a child born with a chromosome imbalance is as high as 50%.
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- 2011
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208. Structural and depositional evolution of the East Balkan thrust belt, Bulgaria
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Michal Nemcok, Chelsea Welker, Eric R. Higgins, David P. Meaux, Dian Vangelov, and Charles J. Stuart
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geography ,geography.geographical_feature_category ,Continental crust ,Energy Engineering and Power Technology ,Geology ,Fold (geology) ,Thermal subsidence ,Sedimentary depositional environment ,Paleontology ,Fuel Technology ,Geochemistry and Petrology ,Fold and thrust belt ,Earth and Planetary Sciences (miscellaneous) ,Piggyback basin ,Paleogene ,Foreland basin - Abstract
Analysis of structural and sedimentologic data from onshore outcrops, offshore wells, and offshore seismic profiles indicates that the thrust belt geometry in eastern Bulgaria from the Paleocene to the Holocene is characterized by a southeastward plunge toward the western Black Sea Basin. This plunge was caused by (1) a combination of eastward-thinning continental crust in the west and oceanic crust in the east; (2) a postrift thermal subsidence of the continental crust; (3) buttressing and no buttressing of the Moesian platform against the thrust belt in its western and eastern parts, respectively; and (4) northeastward thrust belt advance. These factors controlled the overall eastward-diminishing uplift of the thrust belt and associated eastward sediment funneling into the Black Sea. Evidence for the eastward-fading uplift and buttressing includes the (1) eastward decreasing amount of shortening along constructed cross sections, yielding 30, 10.5, 11, and 4 km (18.6, 6.5, 6.8, and 2.5 mi, respectively) from west to east, respectively; (2) eastward trend of more complete stratigraphic sections and shallower erosional levels; and (3) eastward increase in decollement depths, being 3.7, 3.8, 9.5 to 13.5, and 12.3 to 14.1 km (2.3, 2.4, 5.9–8.4, and 7.6–8.8 mi). The age of the last thrusting is progressively younger toward the east from the middle Eocene through the late Eocene to the Oligocene from west to east, respectively. Onshore parts of the thrust belt, which were significantly affected by buttressing against the Moesian platform, exhibit thrusting followed by late Eocene gravitational collapse, Oligocene quiescence, and Neogene extension. The thrust belt part farther east exhibits thrusting followed by Oligocene–Neogene extension. A Paleocene–middle Eocene piggyback basin formed in the onshore part of the thrust belt, centered in the East Balkan zone, with a southeastward-plunging axis, which migrated northeastward with basin shortening and filling. The development of the East Balkan thrust belt and its later extensional modification had a dominant control over sediment transport, lithofacies, and depositional patterns. Developing thrust belt fold structures, together with the orogenic hinterland and highs in the foreland, formed a northeastward and eastward expanding system of sediment input. Southeastward-plunging axes of the foreland basin and the Paleocene–middle Eocene piggyback basin were the principal sediment transport pathways, together with subordinate internal synclinal axes. These depressions funneled sediments toward and into the western Black Sea Basin. As orogenesis advanced to the northeast, former depositional areas were uplifted and eroded, providing local sources of sediment.
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- 2011
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209. A Random Control Trial of Contrast Baths and Ice Baths for Recovery during Competition in U/20 Rugby Union
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Ian Heazlewood, Mike Climstein, and Trevor R. Higgins
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Male ,Adolescent ,Treatment outcome ,Football ,Passive recovery ,Physical Therapy, Sports Therapy and Rehabilitation ,Field tests ,Phosphates ,Young Adult ,Animal science ,Heart Rate ,Humans ,Orthopedics and Sports Medicine ,Statistical analysis ,Fatigue ,Mathematics ,Ice ,Significant difference ,Contrast (statistics) ,Repeated measures design ,Baths ,Recovery of Function ,General Medicine ,Mental Fatigue ,Treatment Outcome ,Cryotherapy ,Exercise Test - Abstract
Higgins, TR, Heazlewood, IT, and Climstein, M. A random control trial of contrast baths and ice baths for recovery during competition in U/20 rugby union. J Strength Cond Res 25(4): 1046-1051, 2011-Players in team sports must recover in a relatively short period of time to perform at optimal levels. To enhance recovery, cryotherapy is widely used. To date, there are limited scientific data to support the use of cryotherapy for recovery. Players (n = 26) from a premier rugby club volunteered to participate in a random control trial (RCT) using contrast baths, ice baths, and no recovery. Statistical analysis, between group and within group, with repeated measures was conducted along with determination of effect sizes in 2 field tests. Pre and postfield tests including a 300-m test and a phosphate decrement test and subjective reports were conducted during the RCT. No significant difference was identified between base tests and retests in the phosphate decrement test or the 300-m tests. Effect size calculations identified a medium to large effect (d = 0.72) for 300-m tests for contrast baths against control. Trivial effects were identified for ice baths (d = 0.17) in the 300-m test against control. Effect size calculations in the phosphate decrement test showed a trivial effect (d = 0.18) contrast baths and a negative effect (d = −0.62) for ice baths. Treatment-treatment analysis identified a large effect for contrast baths (d = 0.99) in the phosphate decrement test and a medium effect for contrast baths (d = 0.53) in the 300-m test. Effect scores across contrast baths, ice baths, and passive recovery along with subjective reports indicate a trend toward contrast baths benefiting recovery in rugby. The continued use of 5-minute ice baths for recovery should be reconsidered based on this research because trends suggest a detrimental effect.
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- 2011
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210. Multiplex signal transmission and the development of sampling techniques: the work of Herbert Raabe in contrast to that of Claude Shannon
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P. Seidler, Paul L. Butzer, Paulo J. S. G. Ferreira, O. Lange, J. R. Higgins, M.M. Dodson, and R. L. Stens
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Digital Multiplex System ,business.industry ,Applied Mathematics ,Sampling (statistics) ,Context (language use) ,Information theory ,Nyquist–Shannon sampling theorem ,Telephony ,business ,German literature ,Mathematical economics ,Analysis ,Telegraphy ,Mathematics - Abstract
This article discusses the interplay between multiplex signal transmission in telegraphy and telephony, and sampling methods. It emphasizes the works of Herbert Raabe (1909–2004) and Claude Shannon (1916–2001) and the context in which they occurred. Attention is given to the role that the exceptional research atmosphere in Berlin during the 1920s and early 1930s played in the development of some of the ideas underlying these works, first in Germany and then in the USA, as some of the protagonists moved there. Raabe's thesis, published in 1939, describes and analyses a time-division multiplex system for telephony. In order to build his working prototype, Raabe had to develop the theoretical tools he needed and achieved a thorough understanding of sampling, including sampling with pulses of finite duration and sampling of low-pass and band-pass signals. His condition for reconstruction was known as ‘Raabe's condition’ in the German literature of the time. On the other hand, Shannon's works of 1948 and 1949 ...
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- 2011
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211. The sampling theorem, Poisson's summation formula, general Parseval formula, reproducing kernel formula and the Paley–Wiener theorem for bandlimited signals – their interconnections
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J. R. Higgins, Paul L. Butzer, Gerhard Schmeisser, R. L. Stens, and Paulo J. S. G. Ferreira
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Discrete mathematics ,Liouville's formula ,Factor theorem ,Paley–Wiener theorem ,Applied Mathematics ,Poisson summation formula ,Whittaker–Shannon interpolation formula ,Parseval's theorem ,symbols.namesake ,symbols ,Nyquist–Shannon sampling theorem ,Analysis ,Cauchy's integral formula ,Mathematics - Abstract
It is shown that the Whittaker–Kotel'nikov–Shannon sampling theorem of signal analysis, which plays the central role in this article, as well as (a particular case) of Poisson's summation formula, the general Parseval formula and the reproducing kernel formula, are all equivalent to one another in the case of bandlimited functions. Here equivalent is meant in the sense that each is a corollary of the other. Further, the sampling theorem is equivalent to the Valiron–Tschakaloff sampling formula as well as to the Paley–Wiener theorem of Fourier analysis. An independent proof of the Valiron formula is provided. Many of the equivalences mentioned are new results. Although the above theorems are equivalent amongst themselves, it turns out that not only the sampling theorem but also Poisson's formula are in a certain sense the ‘strongest’ assertions of the six well-known, basic theorems under discussion.
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- 2011
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212. Hemostasis in Pre-Eclampsia
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S.K. Ismail and John R. Higgins
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medicine.medical_specialty ,Preeclampsia ,Pre-Eclampsia ,Pregnancy ,medicine ,Humans ,Thrombophilia ,Placental Circulation ,Hemostasis ,Eclampsia ,Aspirin ,business.industry ,Obstetrics ,Placentation ,Hypertension, Pregnancy-Induced ,Hematology ,Heparin, Low-Molecular-Weight ,medicine.disease ,Uteroplacental Circulation ,Gestation ,Female ,Cardiology and Cardiovascular Medicine ,business - Abstract
Pre-eclampsia (P-EC) is a multisystem disorder exclusive to pregnancy. It complicates ~2 to 8% of all pregnancies and remains a major cause of maternal mortality. P-EC is characterized by a profound hypercoagulable state. The delicate hemostatic balance that must be maintained in the uteroplacental circulation during pregnancy makes this system vulnerable to perturbation. An abnormal hemostatic pattern occurs within the uteroplacental circulation in P-EC compared with normal pregnancy. Much recent research has focused on the epidemiological link between inherited thrombophilia and P-EC. The data suggest a weak statistical association, indicating an improbable primary role in the pathogenesis. Without clear evidence, low molecular weight heparins have been widely used to reduce recurrence of P-EC in thrombophilia-positive women. This practice now should be reviewed. Future research needs to focus on improving our basic scientific understanding of the role of the hemostatic system in human placentation.
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- 2011
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213. Comparing birth plan preferences among Irish and Nigerian women
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G Oyeye, G Oluyede, Carmel P. Sheridan, I Yekinni, K Ogunleye, John R. Higgins, and Kathleen O'Sullivan
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education.field_of_study ,Pregnancy ,business.industry ,Vaginal delivery ,media_common.quotation_subject ,Immigration ,Population ,Birth plan ,medicine.disease ,language.human_language ,Nursing ,Irish ,Maternity and Midwifery ,language ,Medicine ,Gestation ,Observational study ,business ,education ,media_common ,Demography - Abstract
The demographics of the obstetric population in Ireland are increasingly changing due to immigration patterns. As the obstetric population becomes more ethnically diverse, the challenge for health professionals is to provide more appropriate, culturally-specific care. This observational study compared birth plan preferences among Irish and Nigerian pregnant women. Included in this study were 113 Nigerian women and 519 Irish women attending the Unified Maternity Services in Cork. A questionnaire was used to assess patients' attitudes toward varying aspects of obstetric care. Differences between the two study populations were seen across all aspects of care. Among other differences, Nigerian women booked at a later gestation compared to their Irish counterparts (33.8 weeks vs. 20.8 weeks respectively, P < 0.001), preferred to have a vaginal delivery (90.7% vs. 64.2%) and an analgesia-free birth (39.6% vs. 5.8%). This study demonstrates a need to recognize the cultural variations in preferences for pregnancy and childbirth in order to provide culturally-specific care.
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- 2011
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214. Effects of magnesium ions on near-equilibrium calcite dissolution: Step kinetics and morphology
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Man Xu and Steven R. Higgins
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Calcite ,Molality ,Aqueous solution ,Chemistry ,Magnesium ,Kinetics ,Analytical chemistry ,chemistry.chemical_element ,chemistry.chemical_compound ,Crystallography ,Geochemistry and Petrology ,Saturation (chemistry) ,Magnesium ion ,Dissolution - Abstract
Dissolution kinetics at the aqueous solution-calcite ( 1 0 1 ¯ 4 ) interface at 50 °C were investigated using in situ atomic force microscopy (AFM) to reveal the influence of magnesium concentration and solution saturation state on calcite dissolution kinetics and surface morphology. Under near-equilibrium conditions, dissolved Mg 2 + displayed negligible inhibitory effects on calcite dissolution even at concentrations of 10 - 4 molal ( m ) . Upon the introduction of 10 - 3 m Mg 2 + , the solution saturation state with respect to calcite, Ω calcite ( = a Ca 2 + · a CO 3 2 - K sp ( calcite ) ) , acted as a “switch” for magnesium inhibition whereby no significant changes in step kinetics were observed at Ω calcite 0.2 , whereas a sudden inhibition from Mg 2 + was activated at Ω calcite ⩾ 0.2 . The presence of the Ω -switch in dissolution kinetics indicates the presence of critical undersaturation in accordance with thermodynamic principles. The etch pits formed in solutions with 10 - 3 m Mg 2 + exhibited a unique distorted rhombic profile, different from those formed in Mg-free solutions and in de-ionized water. Such unique etch pit morphology may be associated with the anisotropy in net detachment rates of counter-propagating kink sites upon the addition of Mg 2 + .
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- 2011
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215. Dissolution kinetics of calcite at 50–70°C: An atomic force microscopic study under near-equilibrium conditions
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Xiaoming Hu, Man Xu, Steven R. Higgins, and Kevin G. Knauss
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Calcite ,Curvilinear coordinates ,chemistry.chemical_compound ,Crystallography ,Geochemistry and Petrology ,Chemistry ,Atomic force microscopy ,Equilibrium conditions ,Kinetics ,Thermodynamics ,Anisotropy ,Saturation (chemistry) ,Dissolution - Abstract
Direct measurements of calcite ( 10 1 ¯ 4 ) faces were performed using in situ atomic force microscopy (AFM) to reveal the dissolution processes as a function of solution saturation state and temperature. Time-sequential AFM images demonstrated that step velocities at constant temperature increased with increasing undersaturation. The anisotropy of obtuse and acute step velocities appeared to become more significant as solutions approached equilibrium and temperature increased. At saturation state Ω > 0.02, a curvilinear boundary was formed at the intersection of two acute steps and the initially rhombohedral etch pit exhibited a nearly triangular shape. This suggests that the [ 4 ¯ 41 ] a and [ 48 1 ¯ ] a steps may not belong to the calcite-aqueous solution equilibrium system. Further increase in the saturation state (Ω ⩾ 0.3) led to a lack of etch pit formation and dissolution primarily occurred at existing steps, in accordance with Teng (2004) . Analysis of step kinetics at different temperatures yielded activation energies of 25 ± 6 kJ/mol and 14 ± 13 kJ/mol for obtuse and acute steps, respectively. The inconsistencies in etch pit morphology, step anisotropy, and step activation energies from the present study with those of studies far-from-equilibrium can be explained by increased influence of the backward reaction, or growth, near-equilibrium. We propose that the backward reaction occurs preferentially at the acute–acute kink sites. The kinetics and effective activation energies of near-equilibrium calcite dissolution presented in this work provide accurate experimental data under likely CO2 sequestration conditions, and thus are crucial to the development of robust geochemical models that predict the long-term performance of mineral-trapped CO2.
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- 2010
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216. The management of reduced fetal movements in an uncomplicated pregnancy at term: Results from an anonymous national online survey in the Republic of Ireland
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Richard P. Horgan, Richard A. Greene, John R. Higgins, and Julia Unterscheider
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Male ,Pediatrics ,medicine.medical_specialty ,MEDLINE ,Reduced fetal movements ,Gestational Age ,The Republic ,Pregnancy ,Surveys and Questionnaires ,medicine ,Humans ,Practice Patterns, Physicians' ,Fetal Monitoring ,Fetal Movement ,Uncomplicated pregnancy ,business.industry ,Obstetrics and Gynecology ,Gestational age ,medicine.disease ,Pregnancy Complications ,Family medicine ,Practice Guidelines as Topic ,Fetal movement ,Gestation ,Female ,business ,Ireland - Abstract
There is currently inconsistent evidence and clinical guidance on how to best manage a pregnancy complicated by reduced fetal movements. This novel, web-based, anonymous questionnaire evaluated 96 assessment and management approaches from doctors working in obstetrics in the Republic of Ireland who were presented with a clinical scenario of a primigravida concerned about reduced fetal movements at 39+3 weeks' gestation. This study identified a lack of clinical practice guidelines available in maternity hospitals in the Republic of Ireland. We demonstrated that almost all clinicians applied more than one assessment method and that most incorporated a cardiotocograph into their assessment. There was a low uptake of simple symphysio-fundal height measurement and high usage of kickcharts. The minority of clinicians admitted or induced their patients. This survey identified the need for national and international guidelines to ensure safe antepartum care and delivery.
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- 2010
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217. Interpolation and Sampling: E.T. Whittaker, K. Ogura and Their Followers
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Paulo J. S. G. Ferreira, Paul L. Butzer, R. L. Stens, Gerhard Schmeisser, J. R. Higgins, and Saburou Saitoh
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Applied Mathematics ,General Mathematics ,Converse ,Nonuniform sampling ,Calculus ,Sampling (statistics) ,Nyquist–Shannon sampling theorem ,Context (language use) ,Whittaker–Shannon interpolation formula ,Analysis ,Mathematics ,Interpolation theory ,Interpolation - Abstract
The classical sampling theorem has often been attributed to E.T. Whittaker, but this attribution is not strictly valid. One must carefully distinguish, for example, between the concepts of sampling and of interpolation, and we find that Whittaker worked in interpolation theory, not sampling theory. Again, it has been said that K. Ogura was the first to give a properly rigorous proof of the sampling theorem. We find that he only indicated where the method of proof could be found; we identify what is, in all probability, the proof he had in mind. Ogura states his sampling theorem as a “converse of Whittaker’s theorem”, but identifies an error in Whittaker’s work. In order to study these matters in detail we find it necessary to make a complete review of the famous 1915 paper of E.T. Whittaker, and two not so well known papers of Ogura dating from 1920. Since the life and work of Ogura is practically unknown outside Japan, and there he is usually regarded only as an educationalist, we present a detailed overview together with a list of some 70 papers of his which we had to compile. K. Ogura is presented in the setting of mathematics in Japan of the early 20th century. Finally, because many engineering textbooks refer to Whittaker as a source for the sampling theorem, we make a very brief review of some early introductions of sampling methods in the engineering context, mentioning H. Nyquist, K. Kupfmuller, V. Kotel’nikov, H. Raabe, C.E. Shannon and I. Someya.
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- 2010
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218. Herbert Raabe's work in multiplex signal transmission and his development of sampling methods
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O. Lange, J. R. Higgins, P. Seidler, Maurice Dodson, Paul L. Butzer, and Paulo J. S. G. Ferreira
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Computer science ,business.industry ,Sampling (statistics) ,Development (topology) ,Duration (philosophy) ,Work (electrical) ,Control and Systems Engineering ,Signal Processing ,Nyquist–Shannon sampling theorem ,Computer Vision and Pattern Recognition ,Nyquist rate ,Electrical and Electronic Engineering ,Telecommunications ,business ,Mathematical economics ,Software ,Telegraphy - Abstract
This paper discusses the work of Herbert Raabe (1909-2004) and its significance in terms of sampling. Raabe's thesis, published in 1939, represents a milestone in the development of sampling, as pointed out in the historical works of Luke. Raabe built and analysed the first time-division multiplex system for telephony, a task that required of him a thorough understanding of sampling, including sampling with pulses of finite duration and sampling of low-pass and band-pass signals. We analyse his approach, its significance from the viewpoint of sampling, the generality of its conclusions, and also the milieu that lead to his remarkable achievements: the exceptional research climate existing in Berlin at the time he worked. We also examine the connection between ''Raabe's condition'', the work of Harry Nyquist (1924, 1928) on telegraphy and the so-called ''Nyquist rate''. An English translation of the sections of Raabe's dissertation more closely related to sampling is included as an appendix.
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- 2010
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219. The Natural History of Anencephaly
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Keelin O'Donoghue, Noirin Russell, Nidaa Obeidi, and John R. Higgins
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medicine.medical_specialty ,Pregnancy ,Polyhydramnios ,Obstetrics ,business.industry ,Obstetrics and Gynecology ,Prenatal diagnosis ,medicine.disease ,Transplantation ,Natural history ,Shoulder dystocia ,Anencephaly ,medicine ,Gestation ,business ,Genetics (clinical) - Abstract
Objective Early elective termination of pregnancy is the most common outcome of a diagnosis of anencephaly in developed countries. Experience and expertise with management of ongoing pregnancies is limited. We aimed to investigate the natural history of these pregnancies from diagnosis to delivery and to determine timing of death. Method A retrospective review of cases of anencephaly diagnosed between 2003 and 2009 in tertiary-referral university teaching hospitals in Cork. Results The majority of cases (25/26; 96%) were diagnosed prenatally at a median gestation of 21+2 weeks (range 13+4–32+4). The median maternal age was 30 years (range 17–41) and 50% were primigravidae. Seven pregnancies were complicated by polyhydramnios and four deliveries were complicated by shoulder dystocia. The median gestation at delivery was 35 weeks (range 22+5–42+6); 69% of labours were induced at a median gestation of 34 weeks. Six women (6/26; 23%) had a pre-labour intrauterine fetal death and nine women (9/26; 35%) had an intrapartum fetal death. Median neonatal survival time was 55 min (range 10 min to 8 days). Six parents donated neonatal organs for transplantation. Conclusion This study provides useful information for health professionals caring for patients with a diagnosis of anencephaly. The majority of these infants die prior to delivery but short-term survival is possible. Copyright © 2010 John Wiley & Sons, Ltd.
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- 2010
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220. 578: Right instrument, right patient, right time: vacuum and forceps vs. forceps alone
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Fionnuala M. McAuliffe, Sean Daly, Fionnuala Breathnach, Amanda Cotter, Michael J. Turner, Fergal D. Malone, Fiona Cody, Samina Dornan, Peter McParland, Patrick Dicker, Gerard Burke, Elizabeth Tully, John J. Morrison, John R. Higgins, Naomi Burke, Michael Geary, and Mark P. Hehir
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medicine.medical_specialty ,business.industry ,Forceps ,Obstetrics and Gynecology ,Medicine ,business ,Surgery - Published
- 2018
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221. Altered reference ranges for protein C and protein S during early pregnancy: Implications for the diagnosis of protein C and protein S deficiency during pregnancy
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Joanne M Said, Paul Monagle, Vera Ignjatovic, John R. Higgins, Shaun P. Brennecke, and Susan P. Walker
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Adult ,medicine.medical_specialty ,Protein S Deficiency ,Thrombophilia ,Antithrombins ,Protein S ,Pregnancy ,Reference Values ,Protein C deficiency ,Internal medicine ,medicine ,Humans ,Prospective Studies ,Protein S deficiency ,Pregnancy Trimesters ,Blood Coagulation ,biology ,business.industry ,Pregnancy Complications, Hematologic ,Antithrombin ,Protein C Deficiency ,Hematology ,medicine.disease ,Endocrinology ,Gene Expression Regulation ,biology.protein ,Gestation ,Female ,business ,Protein C ,medicine.drug - Abstract
SummaryProtein S, protein C and antithrombin are important regulators of coagulation. While deficiencies of these proteins have been linked to adverse pregnancy outcomes, testing for these deficiencies during pregnancy is limited by the use of non-pregnant reference ranges and a limited understanding of the changes that occur during pregnancy. Although several small studies have previously reported on the activity of these proteins during pregnancy, potentially important changes have been overlooked by continuing to compare the activity during pregnancy with non-pregnant reference ranges. In the current study, we investigated the activity of protein S, protein C and antithrombin during the first half of pregnancy in 440 otherwise asymptomatic women who went on to have uncomplicated singleton pregnancies. Consistent with previous studies, we found that antithrombin activity remained unchanged, while protein S activity decreased significantly to a mean level of 46%. We did not observe a progressive decrease in protein S during the second trimester as several studies have suggested previously. In contrast, we observed a potentially biologically significant increase in protein C activity throughout the first 22 weeks of pregnancy. Given the physiological role of protein C, we postulate that this increase may play a role in maintaining early pregnancy through both an anticoagulant and an inflammatory regulation pathway.
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- 2010
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222. Inherited Thrombophilia Polymorphisms and Pregnancy Outcomes in Nulliparous Women
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Paul Monagle, Anthony J. Borg, Eric K. Moses, Shaun P. Brennecke, John R. Higgins, Susan P. Walker, and Joanne M Said
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Adult ,medicine.medical_specialty ,Thrombomodulin ,Thrombophilia ,Risk Assessment ,Pre-Eclampsia ,Pregnancy ,medicine ,Factor V Leiden ,Humans ,Point Mutation ,Prospective Studies ,Family history ,Prospective cohort study ,Abruptio Placentae ,Methylenetetrahydrofolate Reductase (NADPH2) ,Fetal Growth Retardation ,Polymorphism, Genetic ,Placental abruption ,biology ,Obstetrics ,business.industry ,Homozygote ,Pregnancy Outcome ,Factor V ,Obstetrics and Gynecology ,Odds ratio ,Stillbirth ,medicine.disease ,Logistic Models ,Methylenetetrahydrofolate reductase ,Mutation ,biology.protein ,Female ,Prothrombin ,business - Abstract
OBJECTIVE: To estimate the association between five commonly inherited thrombophilia polymorphisms and adverse pregnancy outcomes in women who had no prior history of adverse pregnancy outcomes or personal or family history of venous thromboembolism. METHODS: Healthy nulliparous women (n2,034) were recruited to this prospective cohort study before 22 weeks of gestation. Genotyping for factor V Leiden, prothrombin gene mutation, methylenetetrahydrofolate reductase enzyme (MTHFR) C677T, MTHFR A1298C, and thrombomodulin polymorphism was performed. Clinicians caring for women were blinded to the results of thrombophilia tests. The primary composite outcome was the development of severe preeclampsia, fetal growth restriction, placental abruption, stillbirth, or neonatal death. RESULTS: Complete molecular results and pregnancy outcome data were available in 1,707 women. These complications were experienced by 136 women (8.0%). Multivariable logistic regression demonstrated two statistically significant findings. Women who carried the prothrombin gene mutation had an odds ratio of 3.58 (95% confidence interval [CI] 1.20–10.61, P.02) for the development of the composite primary outcome. Homozygous carriers of the MTHFR 1298 polymorphism had an odds ratio of 0.26 (95% CI 0.08–0.86, P.03). None of the other polymorphisms studied showed a significant association with the development of the primary outcome in this cohort of women. CONCLUSION: Prothrombin gene mutation confers an increased risk for the development of adverse pregnancy outcomes in otherwise asymptomatic, nulliparous women, whereas homozygosity for MTHFR 1298 may protect against these complications. The majority of asymptomatic women who carry an inherited thrombophilia polymorphism have a successful pregnancy outcome. (Obstet Gynecol 2010;115:5–13) LEVEL OF EVIDENCE: II
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- 2010
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223. Waiting time distributions for clusters of receptors
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Erin R. Higgins, Heiko Schmidle, and Martin Falcke
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Statistics and Probability ,Waiting time ,General Immunology and Microbiology ,Applied Mathematics ,Endoplasmic reticulum ,General Medicine ,Inositol trisphosphate receptor ,General Biochemistry, Genetics and Molecular Biology ,Cytosol ,chemistry.chemical_compound ,chemistry ,Modeling and Simulation ,Biophysics ,Inositol ,General Agricultural and Biological Sciences ,Receptor ,Ion channel ,Control release - Abstract
Inositol 1,4,5-trisphosphate (IP(3)R) receptor channels control release of Ca(2+) from the endoplasmic reticulum into the cytosol of a cell. The binding of both 1,4,5-trisphosphate (IP(3)) and activating Ca(2+) is required for the channel to open. At high Ca(2+) concentrations, IP(3)Rs are inhibited. IP(3)Rs are composed of four identical subunits and form in clusters. Many models have been proposed to describe how the binding of IP(3) and Ca(2+) to subunits results in the opening and closing of IP(3)Rs. Here we compare the opening and closing probability distributions for clusters of IP(3)Rs, resulting from three different models. The distributions are calculated both analytically, using a method we have developed, and with simulations. We found significant differences in the behavior of the three models as the Ca(2+) and IP(3) concentrations are varied.
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- 2009
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224. Expression of Pleiotrophin and its Receptors in Human Placenta Suggests Roles in Trophoblast Life Cycle and Angiogenesis
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M. Carmody, Freda Wynne, Iain T. Cameron, Melanie Ball, Peter Dockery, A. Aigner, John D. Aplin, Tom Moore, Samantha D. Smith, and John R. Higgins
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Angiogenesis ,Mesenchyme ,Gene Expression ,Neovascularization, Physiologic ,Endogenous retrovirus ,Biology ,Pleiotrophin ,Pregnancy ,Cell Line, Tumor ,Placenta ,medicine ,Humans ,Anaplastic Lymphoma Kinase ,Cell Lineage ,Placental Circulation ,Receptor ,Receptor-Like Protein Tyrosine Phosphatases, Class 5 ,Cell Cycle ,Receptor Protein-Tyrosine Kinases ,Obstetrics and Gynecology ,Placentation ,Trophoblast ,Protein-Tyrosine Kinases ,Trophoblasts ,Cell biology ,medicine.anatomical_structure ,Reproductive Medicine ,embryonic structures ,Cancer research ,Cytokines ,Female ,Syndecan-1 ,Syndecan-2 ,Carrier Proteins ,Developmental Biology - Abstract
Pleiotrophin (PTN) is a heparin-binding protein with multiple activities in cell growth, migration and differentiation mediated through multiple receptors. In mammals, PTN expression in trophoblast is found exclusively in the human and in some of the apes in which an endogenous retrovirus upstream of the first coding exon generates a phylogenetically new trophoblast-specific promoter associated with exon UV3. To understand the functions of ERV promoter-mediated trophoblastic PTN expression in pregnancy, we correlated the expression of PTN and its receptors anaplastic lymphoma kinase (ALK), receptor protein tyrosine phosphatase beta/zeta (RPTPbeta/zeta), and Syndecan-1 and Syndecan-3 (SDC1 and SDC3) with key developmental processes in first-trimester human placentation. In an extensive survey of cell lines and primary tissues, we found that trophoblastic transcription of PTN is initiated exclusively from the ERV promoter, whereas decidual expression is initiated at the phylogenetically ancient U1 exon-associated promoter. Using immunohistochemistry, we found that different patterns of overlapping expression of PTN and its receptors occur in different trophoblast subtypes. Notably, a role in angiogenesis is supported by expression of PTN and its receptors in villous mesenchyme, fetal macrophages and villus core fetal vessels. PTN staining of extravillous cytotrophoblasts and the syncytial microvillous membrane is consistent with increasing levels of PTN, as measured by ELISA, in the maternal bloodstream as pregnancy progresses.
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- 2009
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225. A computer program for automated step edge motion analysis from scanning probe microscopy images
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Xiaoming Hu, Brittany D. Campbell, and Steven R. Higgins
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Motion analysis ,Computer program ,business.industry ,Chemistry ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Surfaces and Interfaces ,Edge (geometry) ,Condensed Matter Physics ,Tracking (particle physics) ,Displacement (vector) ,Surfaces, Coatings and Films ,Hough transform ,law.invention ,Scanning probe microscopy ,Optics ,law ,Materials Chemistry ,Canny edge detector ,Computer vision ,Artificial intelligence ,business - Abstract
A computer algorithm was developed to automatically track the displacement of straight step edges between sequential scanning probe microscopy images of single-crystal surfaces. The program utilizes the Canny edge detection algorithm followed by the Hough Transform of the edge map to identify step edges according to their direction, relative to the image axes, and according to their displacement, relative to the image origin. The tracking of individual steps is facilitated by the fact that straight edges in general maintain their direction and therefore, steps of similar displacement but different direction can be sorted. The algorithm is based on the assumption that the rate of image acquisition is much greater than the rate of (mono)layer growth/dissolution, requiring that changes in step displacement are small in successive images. The change in step displacement in sequential images leads directly to the calculation of the step speed. By tabulating all changes in step displacement through a sequence of images, a statistical representation of the step edge data is produced. The program was evaluated using a sequence of 20 atomic force microscopy images from a calcite (104) surface growing from a supersaturated aqueous solution. The program required, in total, 5 CPU-minutes running on a Pentium 4 processor to compute the mean step speed with 60% precision whereas the equivalent number of measurements performed “by hand” required 6 person-hours at 70% precision. For comparable output, the computer program therefore represents a factor of about 100 decrease in required effort.
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- 2009
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226. Gender differences in smoking: A longitudinal study of beliefs predicting smoking in 11–15 year olds
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Gary Fry, Mark Conner, Brendan Gough, Andrea R. Higgins, and Sarah Grogan
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Male ,Health Knowledge, Attitudes, Practice ,Longitudinal study ,Adolescent ,Social pressure ,Developmental psychology ,Sex Factors ,Surveys and Questionnaires ,Humans ,Longitudinal Studies ,Prospective Studies ,Child ,Applied Psychology ,Risk behaviour ,Smoking ,Public Health, Environmental and Occupational Health ,General Medicine ,General Chemistry ,humanities ,Large sample ,Cross-Sectional Studies ,England ,behavior and behavior mechanisms ,Normative ,Female ,Smoking status ,Psychology ,Clinical psychology - Abstract
This longitudinal study investigated differences in beliefs and perceived behavioural control between smokers and non-smokers in a large sample of adolescents. Positive and negative instrumental beliefs, normative beliefs, perceived behavioural control (PBC) and smoking status were assessed in the same participants at 11, 13 and 15 years of age. Prospective analyses among non-smokers revealed that for boys, negative instrumental beliefs in non-smokers at age 11 predicted smoking at age 15 years. For girls, normative beliefs and PBC in non-smokers at age 11 predicted smoking status at age 13; normative beliefs at age 11 predicted smoking at age 15; and positive instrumental beliefs and normative beliefs at age 13 predicted smoking status at age 15. Cross-sectional data revealed that smokers were significantly more likely than non-smokers to endorse positive instrumental beliefs, less likely to agree with negative instrumental belief items, more likely than non-smokers to perceive social pressure to smoke, and less likely to report control over smoking, and that female smokers reported less control over smoking and fewer negative instrumental beliefs than all other groups including male smokers at age 13. The need for belief-based preventative interventions that are age- and gender-relevant is discussed.
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- 2009
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227. The prevalence of inherited thrombophilic polymorphisms in an asymptomatic Australian antenatal population
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Susan P. Walker, Joanne M Said, Janine Campbell, Anthony J. Borg, John R. Higgins, Eric K. Moses, Shaun P. Brennecke, Paul Monagle, and Valerie J Bryant
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Heterozygote ,medicine.medical_specialty ,Thrombomodulin ,Population ,Thrombophilia ,Asymptomatic ,Blood Coagulation Disorders, Inherited ,Gene Frequency ,Pregnancy ,Prevalence ,Factor V Leiden ,medicine ,Humans ,Genetic Predisposition to Disease ,Family history ,education ,Allele frequency ,Methylenetetrahydrofolate Reductase (NADPH2) ,Gynecology ,education.field_of_study ,Polymorphism, Genetic ,biology ,business.industry ,Obstetrics ,Homozygote ,Australia ,Pregnancy Outcome ,Factor V ,Obstetrics and Gynecology ,General Medicine ,medicine.disease ,Methylenetetrahydrofolate reductase ,Mutation ,biology.protein ,Female ,Prothrombin ,medicine.symptom ,business - Abstract
Aim: Inherited thrombophilic polymorphisms have been linked to pregnancy-related thromboembolism and other adverse pregnancy outcomes. As there are limited data on the prevalence of these polymorphisms in Australian populations, we aimed to assess this in an antenatal population. Methods: Healthy nulliparous women (n = 2031) were recruited to this study. The women had no past or family history of venous thromboembolism. Women were excluded if they or a family member was known to be a carrier of any thrombophilic marker. Genotyping from venous blood for the factor V Leiden, prothrombin 20210A, MTHFR 677 and 1298 and thrombomodulin C1418T polymorphisms was undertaken. Results: Key findings were that 107 of 2019 (5.30, 95% confidence interval 4.36–6.37%) women tested were heterozygous carriers of factor V Leiden and one was homozygous (0.05, 0–0.27%); 2.43% of women were heterozygous carriers of the prothrombin gene mutation (1.80–3.20%) while no women were homozygous for this mutation; 11.62% (10.22–13.02%) and 9.98% (8.67–11.29%) were homozygous for the MTHFR 677 and 1298 polymorphisms, respectively, and 3.43% (2.63–4.22%) of women were homozygous for the thrombomodulin polymorphism. Conclusions: The prevalence of these polymorphisms is consistent with previously published data in Caucasian populations. These data will provide the basis for further assessment of the relationship between poor pregnancy outcome and these inherited thrombophilic polymorphisms in an asymptomatic antenatal population.
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- 2008
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228. Model nucleation and growth studies of nanoscale oxide coatings suitable for modification of microcellular and nano-structured carbon
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Rajasekhar V. Pulikollu, Sharmila M. Mukhopadhyay, and Steven R. Higgins
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Materials science ,Nucleation ,Oxide ,Analytical chemistry ,Surfaces and Interfaces ,General Chemistry ,engineering.material ,Condensed Matter Physics ,Surfaces, Coatings and Films ,Overlayer ,chemistry.chemical_compound ,Coating ,X-ray photoelectron spectroscopy ,chemistry ,Chemical engineering ,Nano ,Materials Chemistry ,engineering ,Graphite ,Nanoscopic scale - Abstract
In this paper, a detailed study of the nucleation and growth of plasma assisted oxide coatings on model graphitic substrates has been performed. The surface chemistry and morphology of these films (as they grow on graphite) have been monitored using X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). It is shown that oxide coatings start as islands having average height of 3–5 nm. The density and lateral size of these islands grow to form complete layers. Therefore complete and smooth coverage can be obtained with a film thickness in the range of a few nanometers (3–5 nm). The coating chemical composition is identical to SiO2. Detailed XPS analysis during overlayer growth reveals the presence of strong –Si–C– bonds at the graphite–coating interface. This is an important finding that can help to predict the mechanical, thermal and other functional properties of the interface. The durability of this coating at high operating temperatures has been investigated, and it is found to withstand up to 1000 °C heat treatments in argon environment.
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- 2008
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229. Relative Levels of M-CSF and GM-CSF Influence the Specific Generation of Macrophage Populations during Infection with Mycobacterium tuberculosis
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Mercedes Gonzalez-Juarrero, Eric J. Lee, Adrian G. Rosas-Taraco, Ian M. Orme, Jonathan R. Higgins, Joaquin Sanchez-Campillo, and David M. Higgins
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CD4-Positive T-Lymphocytes ,Tuberculosis ,medicine.medical_treatment ,Immunology ,Cell Count ,C-C chemokine receptor type 7 ,Sensitivity and Specificity ,Mycobacterium tuberculosis ,Interferon-gamma ,Mice ,Transforming Growth Factor beta ,medicine ,Animals ,Immunology and Allergy ,Macrophage ,Cells, Cultured ,MHC class II ,biology ,Macrophage Colony-Stimulating Factor ,Macrophages ,Histocompatibility Antigens Class II ,Granulocyte-Macrophage Colony-Stimulating Factor ,Dendritic Cells ,biology.organism_classification ,Acquired immune system ,medicine.disease ,Phenotype ,Cytokine ,Chronic Disease ,Disease Progression ,biology.protein ,Female ,Lymphocyte Culture Test, Mixed ,Biomarkers - Abstract
Members of the CSF cytokine family play important roles in macrophage recruitment and activation. However, the role of M-CSF in pulmonary infection with Mycobacterium tuberculosis is not clear. In this study, we show the lungs of mice infected with M. tuberculosis displayed a progressive decrease in M-CSF in contrast to increasing levels of GM-CSF. Restoring pulmonary M-CSF levels during infection resulted in a significant decrease in the presence of foamy macrophages and increased expression of CCR7 and MHC class II, specifically on alveolar macrophages. In response to M-CSF, alveolar macrophages also increased their T cell-stimulating capacity and expression of DEC-205. These studies show that the levels of expression of M-CSF and GM-CSF participate in the progression of macrophages into foamy cells and that these cytokines are important factors in the differentiation and regulation of expression of dendritic cell-associated markers on alveolar macrophages. In addition, these studies demonstrate that M-CSF may have a role in the adaptive immune response to infection with M. tuberculosis.
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- 2008
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230. Dissolution kinetics and topographic relaxation on celestite (001) surfaces: The effect of solution saturation state studied using Atomic Force Microscopy
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Xiaoming Hu, Sweta Bose, and Steven R. Higgins
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Geochemistry and Petrology ,Atomic force microscopy ,Chemistry ,Kinetics ,Nucleation ,Step edges ,Mineralogy ,Thermodynamics ,Saturation (chemistry) ,Dissolution ,Ion - Abstract
Dissolution of celestite (0 0 1) was studied by atomic force microscopy as a function of solution undersaturation. In solutions near saturation with respect to celestite, dissolution of the mineral took place exclusively by removal of ions from existing step edges. The onset of etch pit nucleation was observed at a critical saturation state of Ω crit ∼ 0.1 ( = [ Sr 2 + ] [ SO 4 2 - ] / K sp ) . Below this saturation state, dissolution took place both at existing step edges and via the creation of new steps surrounding the etch pits. The dissolution rates of celestite exhibited a non-linear dependence on saturation state. Basic crystal dissolution/growth models were inadequate to describe the non-linearity, but a model that incorporates a critical undersaturation provided an improved fit to data collected at high undersaturation. A simple model for dissolution at low undersaturation also fit the rate data well, but in light of the conditions necessary to produce new step edges, the rate coefficient in this model is poorly constrained due to the effects of sample surface history. Consideration of the process of topographic relaxation, consisting of changes in the surface microtopography (i.e., step density) resulting from changes in solution conditions, led to predicted relaxation times on the order of days for the celestite–water interface.
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- 2008
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231. Prevalence of Migraine Headaches in Patients With Congenital Heart Disease
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Adam Tanious, Leo Slavin, Jonathan M. Tobis, Joseph K. Perloff, James R. Higgins, Malika Chowdhry, A. R. Puri, Ramin Kashani, Tam Huu Truong, Philip Cheung, and John S. Child
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Adult ,Heart Defects, Congenital ,Male ,medicine.medical_specialty ,Heart disease ,Migraine Disorders ,Population ,Coronary Circulation ,Internal medicine ,Epidemiology ,Prevalence ,medicine ,Humans ,education ,Retrospective Studies ,education.field_of_study ,Vascular disease ,business.industry ,Retrospective cohort study ,Middle Aged ,medicine.disease ,Surgery ,Migraine ,Patent foramen ovale ,Cardiology ,Female ,Headaches ,medicine.symptom ,Cardiology and Cardiovascular Medicine ,business - Abstract
The prevalence of migraine headaches (MH) is 12% in the general population and increases to 40% in patients with patent foramen ovale. This study evaluated the prevalence of MH in patients with congenital heart disease (CHD). Of 466 patients contacted from the UCLA Adult Congenital Heart Disease Center, 395 (85%) completed a questionnaire to determine the prevalence of MH. Patients were stratified by diagnosis of right-to-left, left-to-right, or no shunt. A group of 252 sex-matched patients with acquired cardiovascular disease served as controls. The prevalence of MH was 45% in adults with CHD compared to 11% in the controls (p50% reduction in headache days per month. In conclusion, the prevalence of MH in all groups of adults with CHD is 3 to 4 times more than a sex-matched control population, with increasing prevalence of MH in patients with no shunt, left-to-right, and right-to-left shunt. The higher than expected frequency of MH in patients with CHD without an intracardiac shunt, suggests additional mechanisms to explain the significant association with MH.
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- 2008
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232. Mark IV Vs A7V : Villers-Bretonneux 1918
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David R. Higgins and David R. Higgins
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- A7V (Tank), World War, 1914-1918--Tank warfare, Mark IV (Tank), Lys, Battle of the, 1918
- Abstract
The German A7V and the British Mark IV were similar in weight, size, and speed, but differed significantly in armour, armament and maneuverability. The A7V had thicker armour, and had nearly double the horsepower per ton. The Mark IV's pair of side-mounted 6pdr cannons forced the vehicle to present its side arc to an enemy in order to fire one of its main guns. Possessing twice as many machine guns as the Mark IV, the A7V had a frontally mounted 57mm gun that proved capable of defeating the Mark IV's armour. The Mark IV's rhomboid design proved superior in crossing trenches, climbing obstacles and moving over rough terrain. As the first tank-versus-tank engagement in history, the fighting around Villers-Bretonneux showcased the British Mark IV and German A7V designs. Although not purpose-built to combat enemy armour, both vehicles proved the viability of such operations, which during the postwar period led to key advances in suspension, armour, gunsights, ammunition, and command and control. While the British continued to develop their armoured forces, German armour development never materialized, and only in the postwar period did they address the issue.
- Published
- 2014
233. Utility of interphase FISH to stratify patients into cytogenetic risk categories at diagnosis of AML in an Eastern Cooperative Oncology Group (ECOG) clinical trial (E1900)
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Martin S. Tallman, Haesook T. Kim, Gail H. Vance, Gordon W. Dewald, Hugo F. Fernandez, Gary A. Hicks, Athena M. Cherry, Rachael L. Hulshizer, and Rodney R. Higgins
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Oncology ,Cancer Research ,medicine.medical_specialty ,Concordance ,Antineoplastic Agents ,Risk category ,Bone Marrow ,Internal medicine ,medicine ,Chromosomes, Human ,Humans ,Interphase ,In Situ Hybridization, Fluorescence ,Chromosome Aberrations ,business.industry ,Cytogenetics ,DNA, Neoplasm ,Hematology ,Middle Aged ,Prognosis ,Minimal residual disease ,Chromosome Banding ,Clinical trial ,medicine.anatomical_structure ,Leukemia, Myeloid ,Karyotyping ,Acute Disease ,%22">Fish ,Bone marrow ,DNA Probes ,business ,Kappa - Abstract
We evaluated the efficacy of FISH to detect chromosome anomalies in the evaluation of young (
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- 2007
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234. Free Communications: Lymphoproliferative Disorders
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Buck Gan., Lorna M. Secker-Walker, Christine J. Harrison, Letizia Foroni, Mark R. Litzow, Susan M. Richards, Rodney R. Higgins, Anthony V. Moorman, P H Wernik, Ah Goldstone, Jacob M. Rowe, Martin S. Tallman, Gordon W. Dewald, Elisabeth Paietta, Adele K. Fielding, Athena M. Cherry, Gail H. Vance, and M Martineau
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Oncology ,medicine.medical_specialty ,Prognostic factor ,business.industry ,Internal medicine ,medicine ,Lymphoblastic leukaemia ,Karyotype ,Hematology ,business - Published
- 2007
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235. Structure and reactivity of the dolomite (104)–water interface: New insights into the dolomite problem
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Steven R. Higgins, Zhan Zhang, Changyong Park, Xiaoming Hu, Neil C. Sturchio, and Paul Fenter
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chemistry.chemical_compound ,Supersaturation ,Crystallography ,Chemical engineering ,Geochemistry and Petrology ,Chemistry ,Dolomite ,Surface force ,Carbonate ,Reactivity (chemistry) ,Surface layer ,Layer (electronics) ,Stoichiometry - Abstract
The structure and reactivity of the dolomite (104)–water interface was probed in situ with high resolution X-ray reflectivity and surface force microscopy at room temperature. Measurements in stoichiometric solutions alternating between saturated and supersaturated (log IAP/K = 2.3) conditions show that the dolomite surface termination readily changes in response to solution composition, but these changes are self-limiting and partially irreversible. The freshly cleaved dolomite (104) surface in contact with the saturated solution has a stoichiometric termination, a distinct surface hydration layer and small surface structural displacements, similar to those observed previously at the calcite–water interface. After reaction with supersaturated solutions dolomite is terminated by a two-layer thick Ca-rich film with substantial structural displacements of the cations. With subsequent exposure to a saturated solution this surface was transformed to an interfacial structure different from the freshly cleaved surface, having a reduced density of the outermost surface layer and a Ca-rich second layer. These results provide new insight into the lack of dolomite growth in modern carbonate environments (i.e., the “dolomite problem”), suggesting that this behavior is associated with a combination of thermodynamic and kinetic factors, including (1) growth of compositionally modified epitaxial CaXMg2−X(CO3)2 layers having thicknesses limited by lattice strain, (2) slow incorporation of Mg during layer growth, and (3) partial irreversibility of surface reactions.
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- 2007
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236. Preventing Diabetic Foot Ulcer Recurrence in High-Risk Patients
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George Constantinides, Kyriacos A. Athanasiou, David G. Armstrong, Kevin R. Higgins, C. Mauli Agrawal, Dan R. Lanctot, Ruben G. Zamorano, and Lawrence A. Lavery
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Advanced and Specialized Nursing ,medicine.medical_specialty ,medicine.diagnostic_test ,business.industry ,Endocrinology, Diabetes and Metabolism ,Physical examination ,medicine.disease ,Diabetic foot ,law.invention ,Diabetic foot ulcer ,Peripheral neuropathy ,Randomized controlled trial ,law ,Multicenter trial ,Diabetes mellitus ,Internal Medicine ,medicine ,Physical therapy ,business ,Foot (unit) - Abstract
OBJECTIVE—The purpose of this study was to evaluate the effectiveness of a temperature monitoring instrument to reduce the incidence of foot ulcers in individuals with diabetes who have a high risk for lower extremity complications. RESEARCH DESIGN AND METHODS—In this physician-blinded, randomized, 15-month, multicenter trial, 173 subjects with a previous history of diabetic foot ulceration were assigned to standard therapy, structured foot examination, or enhanced therapy groups. Each group received therapeutic footwear, diabetic foot education, and regular foot care. Subjects in the structured foot examination group performed a structured foot inspection daily and recorded their findings in a logbook. If standard therapy or structured foot examinations identified any foot abnormalities, subjects were instructed to contact the study nurse immediately. Subjects in the enhanced therapy group used an infrared skin thermometer to measure temperatures on six foot sites each day. Temperature differences >4°F (>2.2°C) between left and right corresponding sites triggered patients to contact the study nurse and reduce activity until temperatures normalized. RESULTS—The enhanced therapy group had fewer foot ulcers than the standard therapy and structured foot examination groups (enhanced therapy 8.5 vs. standard therapy 29.3%, P = 0.0046 and enhanced therapy vs. structured foot examination 30.4%, P = 0.0029). Patients in the standard therapy and structured foot examination groups were 4.37 and 4.71 times more likely to develop ulcers than patients in the enhanced therapy group. CONCLUSIONS—Infrared temperature home monitoring, in serving as an “early warning sign,” appears to be a simple and useful adjunct in the prevention of diabetic foot ulcerations.
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- 2007
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237. Gestational hypertensive disease in twin pregnancy: Influence on outcomes in a large national prospective cohort
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Mark P. Hehir, Rhona Mahony, Fionnuala M. McAuliffe, Shane Higgins, Patrick Dicker, Fionnuala Breathnach, John R. Higgins, Gerard Burke, Alyson Hunter, Fergal D. Malone, Sean Daly, John J. Morrison, Michael Geary, and Elizabeth Tully
- Subjects
Gestational hypertension ,Pediatrics ,medicine.medical_specialty ,Neonatal intensive care unit ,Birth weight ,Body Mass Index ,03 medical and health sciences ,0302 clinical medicine ,Pregnancy ,Prevalence ,Medicine ,Birth Weight ,Humans ,030212 general & internal medicine ,Prospective Studies ,Prospective cohort study ,Twin Pregnancy ,030219 obstetrics & reproductive medicine ,business.industry ,Obstetrics ,Cesarean Section ,Obstetrics and Gynecology ,General Medicine ,Hypertension, Pregnancy-Induced ,medicine.disease ,Parity ,Intensive Care, Neonatal ,Pregnancy, Twin ,Gestation ,Female ,business ,Cohort study - Abstract
Objective Gestational hypertensive disease (GHD) is associated with pregnancy-related complications and poor maternal and fetal outcomes in singleton pregnancies. We sought to examine the influence of GHD in a large prospective cohort of twin pregnancies. Study design The ESPRIT study was a national multicenter observational cohort study of 1028 structurally normal twin pregnancies. Each pregnancy underwent sonographic surveillance with two-week ultrasound from 24 weeks for dichorionic and from 16 weeks for monochorionic gestations. Characteristics and demographics as well as labour and delivery outcome data were prospectively recorded. Perinatal mortality, admission to the neonatal intensive care unit (NICU) and a composite of morbidity of respiratory distress syndrome, hypoxic ischaemic encephalopathy, periventricular leukomalacia, necrotising enterocolitis and sepsis were documented for all cases. Outcomes for patients with documented GHD (pre-eclampsia and gestational hypertension) were compared with those without GHD. Results Perinatal outcome data were recorded for 977 patients. Women with GHD had a higher body mass index (27.1 ± 6.4 vs 25.2 ± 4.5, P < 0.0001) than those without and were more likely to be nulliparous (65% (59/92) vs 46% (407/885), P = 0.001). Both groups had similar mean birthweights, but those with GHD were more likely to have a birthweight discordance ≥18% (35% (32/92) vs 20% (179/885), P = 0.001). Rates of caesarean delivery were higher in those twin pregnancies affected by GHD, and while the rate of composite morbidity was similar in both groups, twins in the GHD group had higher rates of NICU admission. Conclusion In twin gestations, gestational hypertension independently confers an increased risk for emergency caesarean delivery, birthweight discordance and NICU admission, such that intensive maternal–fetal monitoring is justified when hypertension develops in a twin pregnancy.
- Published
- 2015
238. Peer Review #2 of 'Partitioning the impact of environment and spatial structure on alpha and beta components of taxonomic, functional, and phylogenetic diversity in European ants (v0.1)'
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R Higgins
- Published
- 2015
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239. P2‐227: A support group for senior caregivers of persons diagnosed with Alzheimer's‐type dementia
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Bernard Comber and Catherine R. Higgins
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medicine.medical_specialty ,Epidemiology ,business.industry ,Health Policy ,medicine.medical_treatment ,Support group ,Alzheimer s type dementia ,Psychiatry and Mental health ,Cellular and Molecular Neuroscience ,Developmental Neuroscience ,medicine ,Neurology (clinical) ,Geriatrics and Gerontology ,business ,Psychiatry - Published
- 2015
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240. FOOTNOTES TO CHAPTER 5
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F. R. Higgins
- Published
- 2015
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241. ADDITIONAL REFERENCES [December 1978]
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F. R. Higgins
- Published
- 2015
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242. FOOTNOTES TO CHAPTER 4
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F. R. Higgins
- Published
- 2015
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243. THE PSEUDO-CLEFT TRANSFORMATION
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F. R. Higgins
- Subjects
Pure mathematics ,Transformation (music) ,Mathematics - Published
- 2015
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244. NOMINALIZATIONS, THE TRANSFORMATIONAL ANALYSIS, AND SYNTACTIC CONNECTEDNESS
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F. R. Higgins
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Transformational leadership ,Social connectedness ,Psychology ,Linguistics ,Nominalization - Published
- 2015
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245. FOOTNOTES TO CHAPTER 2
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F. R. Higgins
- Published
- 2015
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246. SOME SPECIAL PROPERTIES OF SPECIFICATIONAL PSEUDO-CLEFT SENTENCES
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F. R. Higgins
- Published
- 2015
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247. FOOTNOTES TO CHAPTER 6
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F. R. Higgins
- Published
- 2015
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248. The Pseudo-Cleft Construction in English
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F. R. Higgins
- Published
- 2015
- Full Text
- View/download PDF
249. COPULAR SENTENCES AND AMBIGUITY
- Author
-
F. R. Higgins
- Subjects
Computer science ,media_common.quotation_subject ,Ambiguity ,Linguistics ,media_common - Published
- 2015
- Full Text
- View/download PDF
250. FOOTNOTES TO CHAPTER 3
- Author
-
F. R. Higgins
- Published
- 2015
- Full Text
- View/download PDF
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