Biomedical subjects

J R Thompson

Publications and source records attributed to J R Thompson.

At least 19 recordsLinked to original sources

PubMed2007

An evaluation of bivariate random-effects meta-analysis for the joint synthesis of two correlated outcomes.

Often multiple outcomes are of interest in each study identified by a systematic review, and in this situation a separate univariate meta-analysis is usually applied to synthesize the evidence for each outcome independently; an alternative approach is a single multivariate meta-analysis model that utilizes any correlation between outcomes and obtains all the pooled estimates jointly. Surprisingly, multivariate meta-analysis is rarely considered in practice, so in this paper we illustrate the benefits and limitations of the approach to provide helpful insight for practitioners. We compare a bivariate random-effects meta-analysis (BRMA) to two independent univariate random-effects meta-analyses (URMA), and show how and why a BRMA is able to 'borrow strength' across outcomes. Then, on application to two examples in healthcare, we show: (i) given complete data for both outcomes in each study, BRMA is likely to produce individual pooled estimates with very similar standard errors to those from URMA; (ii) given some studies where one of the outcomes is missing at random, the 'borrowing of strength' is likely to allow BRMA to produce individual pooled estimates with noticeably smaller standard errors than those from URMA; (iii) for either complete data or missing data, BRMA will produce a more appropriate standard error of the pooled difference between outcomes as it incorporates their correlation, which is not possible using URMA; and (iv) despite its advantages, BRMA may often not be possible due to the difficulty in obtaining the within-study correlations required to fit the model. Bivariate meta-regression and further research priorities are also discussed.

Analysis of Variance↗

PubMed2007

Standardizing lung function laboratories for multicenter trials.

Multi-center studies provide advantages in clinical research but differences between centers can introduce bias. Three specialist pediatric respiratory laboratories standardized their methodology and examined differences between centers. The specific aims were to (i) assess the variability of measurements on adults within and between centers and (ii) to exchange and cross-analyze data from children to assess the extent of agreement between centers. Each laboratory used identical equipment and software. Inter-laboratory visits were used to (i) standardize protocols for data collection and analysis and (ii) make spirometric and plethysmographic measurements on participating staff at each location. Staff also had repeat measurements in their home laboratories. Measurements from children in each laboratory were exchanged on disk, cross-analyzed, and data compared by ANOVA. There were no significant within-subject, between-center differences in FVC, FEV1, FEF50, FRCpleth, or VC. There was a slight trend for TLC and RV (P=0.07) to be higher at one center. The 95% limits of agreement within and between centers were similar for all parameters. There were no differences between centers in cross-analyzed data from 10 children. By standardizing hardware, software, and protocol, potential inter-laboratory differences can be minimized. We recommend that this approach be adopted prior to multi-center studies.

Adult↗

PubMed2006

High-performance high-TC superconducting wires.

We demonstrated short segments of a superconducting wire that meets or exceeds performance requirements for many large-scale applications of high-temperature superconducting materials, especially those requiring a high supercurrent and/or a high engineering critical current density in applied magnetic fields. The performance requirements for these varied applications were met in 3-micrometer-thick YBa2Cu3O(7-delta) films epitaxially grown via pulsed laser ablation on rolling assisted biaxially textured substrates. Enhancements of the critical current in self-field as well as excellent retention of this current in high applied magnetic fields were achieved in the thick films via incorporation of a periodic array of extended columnar defects, composed of self-aligned nanodots of nonsuperconducting material extending through the entire thickness of the film. These columnar defects are highly effective in pinning the superconducting vortices or flux lines, thereby resulting in the substantially enhanced performance of this wire.

Journal Article↗

PubMed2006

The natural history of overactive bladder and stress urinary incontinence in older women in the community: a 3-year prospective cohort study.

AIMS: This is the first study designed to describe the natural history of stress urinary incontinence (SUI) and overactive bladder (OAB), using validated symptom syndrome severity scores developed for the purpose. METHODS: Two separate but related studies were involved, (i) a clinic sample (N = 2,052) from a randomised controlled trial (RCT) and (ii) a prospective cohort study (N = 12,750) with 3-year follow-up. Subjects in both studies were women aged 40 or more living in the community, approached using similar postal questionnaires. Severity scores using standardised urinary symptoms were derived for SUI and OAB from weightings obtained from logistic regression models of symptoms in relation to urodynamic diagnosis. Symptom severity scores were plotted for baseline and 3 years of follow-up to demonstrate the natural history of the main categories of SUI and OAB. RESULTS: Overactive bladder and SUI syndrome severity scores showed good criterion validity in relation to relevant clinical measures and good test-retest reliability. OAB severity increased progressively with age including a period of accelerated increase in the 60s. In contrast, SUI severity showed two age-related peaks around age 60 and again at age 80. SUI severity also showed a more fluctuating pattern from year to year compared to OAB. CONCLUSIONS: Contrasting patterns of natural history for OAB and SUI syndromes were identified consistent with differences in the patterns of related co-morbidities. Further studies are needed to confirm these findings.

Adult↗

PubMed2006

Parenteral administration of glutamine modulates acute phase response in postparturient dairy cows.

The objective of this study was to investigate whether administration of L-Gln would affect mediators of acute phase response in postparturient dairy cows. Twenty-four multiparous Holstein cows were blocked by the expected day of calving and randomly assigned to 1 of the 3 treatment groups (n = 8/group): 1) i.v. infusion of 10 L of 0.85% NaCl (control), 2) i.v. infusion of 106, or 3) 212 g/d of L-Gln mixed with 10 L of 0.85% NaCl solution; each treatment was given 8 h/d for each of 7 consecutive days starting on d 1 after calving. Blood samples were collected 1 wk before the expected day of parturition as well as on d 0, 7, 14, and 21 after parturition; plasma concentrations of serum amyloid A (SAA), haptoglobin, and lipopolysaccharide-binding protein were measured by ELISA, and alpha(1)-acid glycoprotein was assessed by radial immunodiffusion. Concentrations of SAA, haptoglobin, and alpha(1)-acid glycoprotein increased in control cows after parturition, reaching peak values on d 0 or 7 postpartum (60, 1,093, and 963 microg/mL, respectively). Cows infused with 106 g/d of L-Gln had greater concentrations of SAA in plasma on d 14 and 21 compared with controls (62.8 vs. 30.2 and 71.1 vs. 34.5 microg/mL, respectively). Cows infused with 212 g/d of L-Gln had greater concentrations of SAA on d 7 (82.5 vs. 53.9 microg/mL) and lower concentrations of haptoglobin on d 14 and 21 postpartum compared with controls (264 vs. 621 and 175 vs. 587 microg/mL, respectively). Cows treated with 106 and 212 g/d of L-Gln had greater plasma lipopolysaccharide-binding protein concentrations on d 7 compared with control group (50.0 and 35.6 vs. 10.8 microg/mL, respectively). There were no treatment differences with respect to milk yield and DM intake during the experimental period. In conclusion, our data indicate that i.v. administration of L-Gln modulated acute phase mediators in dairy cows after parturition and warrants further research into the mechanisms behind these effects.

Acute-Phase Proteins↗

PubMed2005

Structure, microstructure, and magnetism in ferrimagnetic bioceramics.

The structural and magnetic properties of ferrimagnetic bioglass ceramics in the system [0.45(CaO,P2O5)(0.52 - x)SiO2 xFe2O3 0.03Na2O], x = 0.05, 0.10, 0.15, 0.20 and heat-treated at the temperature range 600-1100 degrees C are assessed. The structure and microstructure of the samples are characterized with X-ray diffraction, scanning electron microscopy, and energy dispersive X-ray spectroscopy. Calcium phosphate and magnetite develop as the two major crystalline phases. For x = 0.10 and 0.20, calcium phosphate undergoes a gradual transition from the monoclinic to the rhombohedral crystal system (SG P21/a-->R3c) as the heat-treatment temperature increases from 800 to 1100 degrees C. Dendrites of iron oxide with crystallites of various sizes are observed to form within a glassy matrix enriched in calcium, phosphorous, and silicon. Saturation magnetization, remanence, and coercivity are found from dc magnetic measurements. They vary with the specific processing parameters of the composites, and these are correlated with the observed structure and microstructure of the materials.

Biocompatible Materials↗

PubMed2005

Social and visual function in nystagmus.

AIM: To investigate the influence of nystagmus on visual and social function and determine if parents are able to assess visual and social function in children with nystagmus. METHOD: A postal questionnaire comprising 14 questions related to visual function (VF-14) and questions pertaining to social function were sent to all 1013 members of the Nystagmus Network-a UK based organisation for nystagmus sufferers and their families. Visual and social function scores were compared by regression analysis. RESULTS: 180 adult, 233 parent, and 124 child questionnaires were returned. Idiopathic nystagmus was the most common cause. In adults the mean VF-14 score indicated very low visual function, in the same range as patients assessed in low vision services. Children's visual function scored better than adults, between scores of patients with age related macular disease and corneal grafts. There was a strong correlation between perceived visual and social function for adults (p<0.001) and parental assessment of their children (p<0.001), but not between child self assessment of visual and social function. There was strong correlation between parental and child assessment of visual and social function (p<0.001, p<0.001) CONCLUSION: Questionnaires indicated that nystagmus is associated with very low visual function. There is a strong correlation between visual and social impairment. The authors have shown for the first time in an ophthalmic disease that parents are able to estimate the impact of nystagmus on their child both in terms of visual and social functioning, although they underestimate the impact of nystagmus on emotional aspects of wellbeing.

Adolescent↗

PubMed2005

Should acute scaphoid fractures be fixed? A randomized controlled trial.

BACKGROUND: With the proliferation of different fixation screws, there is an increasing trend to recommend early internal fixation of the broken scaphoid even if the fracture is not displaced. The benefits and risks of early fixation of scaphoid fractures have not been established. These were investigated in eighty-eight patients who were of working age with clearly defined minimally displaced or undisplaced bicortical fractures of the waist of the scaphoid. METHODS: Patients who provided informed consent were randomized to treatment with early internal fixation with use of a Herbert screw without a cast (forty-four patients) or to nonoperative treatment for eight weeks with immobilization in a below-the-elbow plaster cast with the thumb left free (forty-four patients). The patients were evaluated at two, eight, twelve, twenty-six, and fifty-two weeks with respect to the severity of pain; tenderness; swelling; wrist movement; grip strength; and symptoms and disability, which were assessed with the Patient Evaluation Measure. In addition, radiographs were made and assessed at each visit. RESULTS: No difference was detected between the groups with respect to age, sex, hand dominance, side of injury, mechanism of injury, or the occupation of the patients. The range of motion, score on the Patient Evaluation Measure, and grip strength were significantly better in the group managed operatively than in the group managed nonoperatively at the eight-week follow-up evaluation, which corresponded with the visit when the cast was removed in that group. Patients returned to work at five to six weeks after the injury in both groups. At twelve weeks, grip strength was better in patients who had had surgery. No significant difference was detected between the two groups with respect to any other outcome measure at any other time. Ten of the forty-four fractures treated nonoperatively had not healed radiographically at twelve weeks, and, as a consequence, the treatment was altered. Complications occurred in thirteen patients who had been managed operatively. All complications were minor, and ten were related to the scar. CONCLUSIONS: This study did not demonstrate a clear overall benefit of early fixation of acute scaphoid fractures beyond the decrease in the rate of a change in treatment because of a delayed union at twelve weeks. Early internal fixation of minimally displaced or nondisplaced fractures of the scaphoid waist, which would heal in a cast, could lead to overtreatment of a large proportion of such fractures, exposing such patients to avoidable surgical risk. Thus, we have adopted a program of so-called aggressive conservative treatment, whereby we carefully assess fracture-healing with plain radiographs, and computed tomography scans if necessary, after six to eight weeks of cast immobilization and recommend surgical fixation with or without bone-grafting at that time if a gap is identified at the fracture site. Such an approach should result in fracture union in over 95% of such patients. LEVEL OF EVIDENCE: Therapeutic Level I.

Acute Disease↗

PubMed2004

Mapping of genetic determinants of the sympathoneural response to stress.

Activation of the sympathoadrenal system (SAS, comprising the sympathetic nervous system and the adrenal medulla) in response to stressful stimuli is an important defense mechanism as well as a contributor to several cardiovascular diseases. There is variability in the SAS response to stress, although the extent to which this is genetically regulated is unclear. Some rodent models, including the hereditary hypertriglyceridemic (hHTg) rat, are hyperresponsive to stress. We investigated whether quantitative trait loci (QTLs) that affect sympathoadrenal response to stress could be identified. Second filial generation rats (n = 189) derived from a cross of the hHTg rat and the Brown Norway rat had plasma norepinephrine (NE) and epinephrine (Epi) levels, indices of activation of the sympathoneural and adrenal medulla components, respectively, measured in the resting state and in response to an immobilization stress. Responses were assessed early (20 min) and late (120 min) after the application of the stress. A genome scan was conducted using 153 microsatellite markers. Two QTLs (maximum peak LOD scores of 4.17 and 3.52, respectively) influencing both the early and late plasma NE response to stress were found on chromosome 10. Together, the QTLs accounted for approximately 20% of the total variation in both the early and late NE responses in the F(2) rats. Interestingly, the QTLs had no effect on plasma Epi response to stress. These findings provide evidence for a genetic determination of the response of a specific component of the SAS response to stress. Genetically determined variation in sympathetic nervous system response to stress may contribute to cardiovascular diseases.

Animals↗

PubMed2004

A new potato virus in a new lineage of picorna-like viruses.

On constructing a cDNA library for potato, 'contaminating' sequences with a significant identity to Apple latent spherical virus (ALSV) were found. Determination of the remaining genome sequence indicated the presence of a bipartite virus with an RNA1 and 2 of 7034 and 3315 nucleotides, respectively, excluding a poly(A)tail. RNA1 encodes a single polyprotein (233 kDa) and shares highest amino acid identity with ALSV at 65%. Conserved amino acid motifs typical for helicase, protease and RNA-dependent polymerase (RdRp) functions are present. RNA2 encodes a single polyprotein (106 kDa) with amino acid identities to the flat apple isolate of Cherry rasp leaf virus (CRLV-FA) (97%) and ALSV (70%), suggesting this is a potato strain of CRLV (CRLV-pot). Phylogenetic analysis using the RdRp region shows that this virus falls within a group separate from the Comoviridae that includes members of the Sequiviridae and the taxonomically unassigned viruses ALSV, Strawberry mottle virus, Satsuma dwarf virus and Navel orange infectious mottling virus. Other regions of the genome have highest identities with both plant and animal infecting members of the picorna-like virus superfamily. The evolutionary context of CRLV-pot and related viruses is discussed. Similar viral sequences from an EST library of peppermint are also analysed.

5' Untranslated Regions↗

PubMed2004

Structural amorphous steels.

Recent advancement in bulk metallic glasses, whose properties are usually superior to their crystalline counterparts, has stimulated great interest in fabricating bulk amorphous steels. While a great deal of effort has been devoted to this field, the fabrication of structural amorphous steels with large cross sections has remained an alchemist's dream because of the limited glass-forming ability (GFA) of these materials. Here we report the discovery of structural amorphous steels that can be cast into glasses with large cross-section sizes using conventional drop-casting methods. These new steels showed interesting physical, magnetic, and mechanical properties, along with high thermal stability. The underlying mechanisms for the superior GFA of these materials are discussed.

Journal Article↗

PubMed2004

Strain diversity and conserved genome elements in Strawberry mild yellow edge virus.

The complete nucleotide sequence of Strawberry mild yellow edge virus isolate D74, and the sequences of a 878 nt region of the coat protein and flanking regions of twenty three isolates of SMYEV were obtained and analysed. The full sequence of the aphid transmissible strain D74 was deduced and found to have an 86% sequence identity to the non-transmissible Agrobacterium infectious MY18 strain. In contrast to isolate MY18 the 5' terminal nucleotides (GAAAAC) of D74 are typical of those from other potexviruses. However, both MY18 and D74 have a non-AUG initiation codon for ORF2 encoding the triple gene block protein 1 (TGB1), and an overlapping TGB3 and coat protein (CP), features unique in the Potexvirus genus. Other conserved features of the genome, including stem-loop structures in the untranslated regions, and motifs common to related viruses are described. The previously postulated ORF6 of MY18 is absent in twenty of the isolates sequenced, including D74. Phylogenetic analysis places all isolates in one of three distinct groups/strains named here I (type-D74), II (type-9Redland), and III (type-MY18), with the majority of isolates, including all European isolates tested, belonging to strain I (type-D74).

Amino Acid Motifs↗

PubMed2004

Carpal tunnel decompression. Is lengthening of the flexor retinaculum better than simple division?

This prospective randomized double-blind control trial compared lengthening and simple division of the flexor retinaculum in carpal tunnel decompression. Twenty-six patients with bilateral carpal tunnel syndrome were randomly allocated to have the flexor retinaculum divided on one side and lengthened on the other. All 52 hands were reviewed at regular intervals up to 25 weeks. The patients, therapists and the final reviewer were unaware of treatment allocation. The Levine symptom and function scores were used to assess the severity of the carpal tunnel syndrome and showed that the two treatments were comparable for relief of carpal tunnel symptoms. The two treatments were also similar for function measured with the Jebsen-Taylor test. There is no identifiable benefit in lengthening the flexor retinaculum when decompressing the carpal tunnel. Moderate or severe pillar and scar pain is common, occurring in 13 of 52 hands after surgery, but only in four by the 12th week and two by the 25th week.

Adult↗

PubMed2004

Blood acylcarnitine levels in normal newborns and heterozygotes for medium-chain acyl-CoA dehydrogenase deficiency: a relationship between genotype and biochemical phenotype?

Patients with medium-chain acyl-CoA dehydrogenase (MCAD) deficiency are unable to metabolize medium-chain fatty acids. Affected patients display a characteristic acylcarnitine profile when blood spots are collected after birth and analysed by tandem mass spectrometry. To determine the potential risk of metabolic decompensation in newborns with elevations of diagnostic metabolites (octanoylcarnitine>0.3, but <1 micromol/L), we investigated the relationship between octanoylcarnitine (C8) concentration in neonatal blood spots and the 985A>G MCAD genotype. Octanoylcarnitine values from 7140 newborns' blood spots were sorted. The highest C8 was approximately 0.7 micromol/L, which is below the range in classical MCAD deficiency. Samples with C8 levels above 0.25 micromol/L (group C) represented 1.4% of the total. Values between 0.05 and 0.25 micromol/L (group B) made up 87.8% of the total; 10.8% of the samples had C8 values less than 0.05 micromol/L (group A). One hundred samples from each group were selected at random and genomic DNA was amplified by PCR and analysed for the presence of the 985A>G mutation. The analysed samples from groups A and B were all homozygous normal. The 100 samples from group C contained 26 samples that were heterozygous for the 985A>G mutation. These findings indicated that the frequency distribution of heterozygotes is not random within this population. Group C was further divided into C1, the 26 heterozygotes, and C2, the remaining 74 newborns in group C. In group C1 only 2 (8%) were in the 'high-risk' group characterized by either low birth weight or requiring admission to the neonatal intensive care unit. In contrast, 28 (38%) from C2 had low birth weight or were in the neonatal intensive care unit. In our dataset, C8/C2 and C8/C12 ratios were also significantly elevated in both groups C1 and C2 compared to controls (group B). In contrast to what others have reported, the ratio of C8/C10 did not differentiate the group B controls from heterozygotes or other patients in metabolic distress (group C2), but were lower than those seen in classic MCAD or mild MCAD deficiency.

Acyl-CoA Dehydrogenase↗

PubMed2004

Analysis of the systemic colonization of cucumber plants by Cucumber green mottle mosaic virus.

Systemic movement of Cucumber green mottle mosaic virus (CGMMV) in cucumber plants was shown to be from photoassimilate source to sink, thus indicating phloem transport. Nevertheless, CGMMV was not detected by immunocytochemical procedures in the intermediary cell-sieve element complex in inoculated cotyledons, where photoassimilate loading occurs. In stem internodes, CGMMV was first localized in the companion cells of the external phloem and subsequently in all tissues except the medulla, therefore suggesting leakage of the virus from, and reloading into, the transport phloem during systemic movement. In systemically infected sink leaves, CGMMV was simultaneously detected in the xylem and phloem. Interestingly, CGMMV accumulated to high levels in the differentiating tracheids of young leaves implying that the xylem could be involved in the systemic movement of CGMMV. This possibility was tested using plants in which cell death was induced in a portion of the stem by steam treatment. At 24 degrees C, steam treatment effectively prevented the systemic movement of CGMMV, even though viral RNA was detected in washes of the xylem above the steamed internode suggesting that xylem circulation occurred. At 29 degrees C, CGMMV systemically infected steam-treated cucumber plants, indicating that CGMMV can move systemically via the xylem. Xylem transport of CGMMV was, however, less efficient than phloem transport in terms of the time required for systemic infection and the percentage of plants infected.

Cotyledon↗

PubMed2004

Early physiological development of infants with intrauterine growth retardation.

OBJECTIVES: To assess the patterns of early postnatal physiological adaptation and maturation in intrauterine growth retarded (IUGR) infants by measuring changes in sleeping deep body temperature, heart rate, and concentrations of urinary cortisol. SETTING: At home. PATIENTS: Sixty five IUGR babies and 127 controls matched for sex, social class, and levels of parental smoking. RESULTS: Night time sleeping deep body temperature, heart rate, and cortisol excretion fell with age, eventually establishing an adult type diurnal rhythm of physiological function. Minimum overnight temperature showed a linear decline with age (p < 0.001), but the IUGR infants and the controls had significant differences in intercept (p = 0.007) and slope (p = 0.02). The estimated rate of decline per week was 0.020 degrees C for IUGR infants and 0.031 degrees C for controls. Maximum temperature did not show similar changes. IUGR infants had a mean (SE) age adjusted minimum overnight heart rate that was 4.2 (1.5) beats/min (p = 0.005) higher than controls. Overnight cortisol/creatinine ratios declined with age at a rate of 4.1% per week (log ratio -0.421 (0.0165), p = 0.01), but the ratio for IUGR infants was on average 42% higher (log ratio 0.35 (0.11), p = 0.002) than for controls of the same age. Morning cortisol concentrations did not show a similar pattern. CONCLUSIONS: Postnatal physiological adaptation and maturation of IUGR infants is slower than normal and therefore they remain in a physiologically immature state for longer. The higher heart rates and greater cortisol excretion in such infants may be precursors to hypertension and cardiovascular disease seen in adults.

Adaptation, Physiological↗

PubMed2003

Efficacy and tolerability of borage oil in adults and children with atopic eczema: randomised, double blind, placebo controlled, parallel group trial.

OBJECTIVE: To study the efficacy and tolerability of borage oil, which contains a high concentration of gamma linolenic acid, in children and adults with atopic eczema. DESIGN: Single centre, randomised, double blind, placebo controlled, parallel group trial. SETTING: Acute district general hospital in Nuneaton, England. PARTICIPANTS: 151 patients, of whom 11 failed to return for assessment, leaving an evaluable population of 140 (including 69 children). INTERVENTION: Adults received four capsules of borage oil twice daily (920 mg gamma linolenic acid), and children received two capsules twice daily, for 12 weeks. MAIN OUTCOME MEASURES: Change in total sign score at 12 weeks measured with the six area, six sign, atopic dermatitis (SASSAD) score (primary endpoint); symptom scores, assessed on visual analogue scales; topical corticosteroid requirement, assessed on a five point scale; global assessment of response by participants; adverse events and tolerability. RESULTS: The mean SASSAD score fell from 30 to 27 in the borage oil group and from 28 to 23 in the placebo group. The difference between the mean improvements in the two groups was 1.4 (95% confidence interval -2.2 to 5.0) points in favour of placebo (P = 0.45). No significant differences occurred between treatment groups in the other assessments. Subset analysis of adults and children did not indicate any difference in response. The treatments were well tolerated. CONCLUSION: Gamma linolenic acid is not beneficial in atopic dermatitis.

Adult↗

PubMed2003

Antiferromagnetic order as the competing ground state in electron-doped Nd1.85Ce0.15CuO4.

Superconductivity in the high-transition-temperature (high-T(c)) copper oxides competes with other possible ground states. The physical explanation for superconductivity can be constrained by determining the nature of the closest competing ground state, and establishing if that state is universal among the high-T(c) materials. Antiferromagnetism has been theoretically predicted to be the competing ground state. A competing ground state is revealed when superconductivity is destroyed by the application of a magnetic field, and antiferromagnetism has been observed in hole-doped materials under the influence of modest fields. None of the previous experiments have revealed the quantum phase transition from the superconducting state to the antiferromagnetic state, because they failed to reach the upper critical field B(c2). Here we report the results of transport and neutron-scattering experiments on electron-doped Nd1.85Ce0.15CuO4 (refs 13, 14), where B(c2) can be reached. The applied field reveals a static, commensurate, anomalously conducting long-range ordered antiferromagnetic state, in which the induced moment scales approximately linearly with the field strength until it saturates at B(c2). This and previous experiments on the hole-doped materials therefore establishes antiferromagnetic order as a competing ground state in the high-T(c) copper oxide materials, irrespective of electron or hole doping.

Journal Article↗