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1.
J Intellect Disabil Res ; 66(1-2): 121-132, 2022 01.
Article in English | MEDLINE | ID: mdl-34213015

ABSTRACT

BACKGROUND: Deficits in executive functioning (EF) have been measured in individuals with developmental disabilities, such as autism spectrum disorder and attention-deficit/hyperactivity disorder, through the use of behaviour rating scales and performance-based assessment. Associations between EF and variables such as challenging and adaptive behaviour have been observed; however, limited research exists on EF profiles in children with heterogeneous developmental delay or with intellectual disability (ID) or the impact of EF on adaptive and challenging behaviour with this population. METHODS: The present study sought to examine the EF profile of 93 children (75 male and 18 female) previously identified with developmental delay in early childhood. EF was assessed using the Behaviour Rating Inventory of Executive Function, Second Edition (BRIEF-2). Children were categorised into an ID group (n = 14) or no ID group (n = 79) based on scores from cognitive and adaptive behaviour assessments. EF profiles were investigated and compared by group. In addition, the impact of EF on both adaptive behaviour and challenging behaviour was measured using hierarchical linear regressions. RESULTS: Statistically significant differences in caregiver-reported EF were not observed between groups; however, both the ID and the no ID group scores were elevated as reported by their caregivers. For the overall sample, caregiver-EF accounted for significant variance in both adaptive (22%) and challenging (68%) behaviour after accounting for child age and sex. CONCLUSIONS: Results indicated deficits in EF for children with and without ID. The significance of EF was accounted for in both adaptive and challenging behaviour for all children in the sample. Future research could elucidate the role of adaptive and challenging behaviour in understanding EF variability among children with histories of developmental delay.


Subject(s)
Attention Deficit Disorder with Hyperactivity , Autism Spectrum Disorder , Adaptation, Psychological , Autism Spectrum Disorder/complications , Caregivers , Child , Child, Preschool , Executive Function , Female , Humans , Male
2.
J Intellect Disabil Res ; 64(10): 739-749, 2020 10.
Article in English | MEDLINE | ID: mdl-32808424

ABSTRACT

BACKGROUND: The COVID-19 pandemic introduced challenges to families with young children with developmental delays. Beyond the widespread concerns surrounding illness, loss of employment and social isolation, caregivers are responsible for overseeing their children's educational and therapeutic programmes at home often without the much needed support of professionals. METHOD: The present study sought to examine the impact of COVID-19 in 77 ethnically, linguistically and socioeconomically diverse families with young children with intellectual and developmental disabilities (IDDs) in California and Oregon, who were participating in larger intervention studies. Parents responded to five interview questions about the impact of the pandemic, services for their child, silver linings or positive aspects, coping and their concerns about the long-term impact of the pandemic. RESULTS: Parents reported that their biggest challenge was being at home caring for their children with the loss of many essential services. Parents reported some positive aspects of the pandemic, especially being together as a family. Although there were positive aspects of the situation, many parents expressed concern about long-term impacts of the pandemic on their children's development, given the loss of services, education and social engagement opportunities. CONCLUSION: Results suggest that parents of young children with IDD report significant challenges at home during the pandemic. Professional support, especially during the reopening phases, will be critical to support family well-being and child developmental outcomes.


Subject(s)
Coronavirus Infections , Developmental Disabilities/nursing , Family , Health Services Accessibility , Intellectual Disability/nursing , Pandemics , Pneumonia, Viral , Adult , COVID-19 , California/ethnology , Child , Child, Preschool , Family/ethnology , Family/psychology , Female , Humans , Male , Oregon/ethnology , Parents
3.
Am J Clin Nutr ; 108(5): 988-996, 2018 11 01.
Article in English | MEDLINE | ID: mdl-30475959

ABSTRACT

Background: The optimal amount of protein intake in critically ill patients is uncertain. Objective: In this post hoc analysis of the PermiT (Permissive Underfeeding vs. Target Enteral Feeding in Adult Critically Ill Patients) trial, we tested the hypothesis that higher total protein intake was associated with lower 90-d mortality and improved protein biomarkers in critically ill patients. Design: In this post hoc analysis of the PermiT trial, we included patients who received enteral feeding for ≥3 consecutive days. Using the median protein intake of the cohort as a cutoff, patients were categorized into 2 groups: a higher-protein group (>0.80 g · kg-1 · d-1) and a lower-protein group (≤0.80 g · kg-1 · d-1). We developed a propensity score for receiving higher protein. Primary outcome was 90-d mortality. We also compared serial values of prealbumin, transferrin, 24-h urinary nitrogen, and 24-h nitrogen balance on days 1, 7, and 14. Results: Among the 729 patients included in this analysis, the average protein intake was 0.8 ± 0.3 g · kg-1 · d-1 [1.0 ± 0.2 g · kg-1 · d-1 in the higher-protein group (n = 365) and 0.6 ± 0.2 g · kg-1 · d-1 in the lower-protein group (n = 364); P < 0.0001]. There was no difference in 90-d mortality between the 2 groups [88/364 (24.2%) compared with 94/363 (25.9%), propensity score-adjusted OR: 0.80; 95% CI: 0.56, 1.16; P = 0.24]. Higher protein intake was associated with an increase in 24-h urea nitrogen excretion compared with lower protein intake, but without a significant change in prealbumin, transferrin, or 24-h nitrogen balance. Conclusions: In the PermiT trial, a moderate difference in protein intake was not associated with lower mortality. Higher protein intake was associated with increased nitrogen excretion in the urine without a corresponding change in prealbumin, transferrin, or nitrogen balance. Protein intake needs to be tested in adequately powered randomized controlled trials targeting larger differences in protein intake in high-risk populations.


Subject(s)
Critical Care/methods , Critical Illness/therapy , Dietary Proteins/administration & dosage , Energy Intake , Enteral Nutrition , Nutritional Requirements , Adult , Aged , Biomarkers/metabolism , Critical Illness/mortality , Dietary Proteins/therapeutic use , Female , Humans , Male , Middle Aged , Nitrogen/metabolism , Prealbumin/metabolism , Transferrin/metabolism , Urea/metabolism
4.
BMC Med Res Methodol ; 18(1): 94, 2018 09 15.
Article in English | MEDLINE | ID: mdl-30219029

ABSTRACT

BACKGROUND: Conducting prospective epidemiological studies of hospitalized patients with rare diseases like primary subarachnoid hemorrhage (pSAH) are difficult due to time and budgetary constraints. Routinely collected administrative data could remove these barriers. We derived and validated 3 algorithms to identify hospitalized patients with a high probability of pSAH using administrative data. We aim to externally validate their performance in four hospitals across Canada. METHODS: Eligible patients include those ≥18 years of age admitted to these centres from January 1, 2012 to December 31, 2013. We will include patients whose discharge abstracts contain predictive variables identified in the models (ICD-10-CA diagnostic codes I60** (subarachnoid hemorrhage), I61** (intracranial hemorrhage), 162** (other nontrauma intracranial hemorrhage), I67** (other cerebrovascular disease), S06** (intracranial injury), G97 (other postprocedural nervous system disorder) and CCI procedural codes 1JW51 (occlusion of intracranial vessels), 1JE51 (carotid artery inclusion), 3JW10 (intracranial vessel imaging), 3FY20 (CT scan (soft tissue of neck)), and 3OT20 (CT scan (abdominal cavity)). The algorithms will be applied to each patient and the diagnosis confirmed via chart review. We will assess each model's sensitivity, specificity, negative and positive predictive value across the sites. DISCUSSION: Validating the Ottawa SAH Prediction Algorithms will provide a way to accurately identify large SAH cohorts, thereby furthering research and altering care.


Subject(s)
Administrative Claims, Healthcare/statistics & numerical data , Algorithms , Hospitalization/statistics & numerical data , Subarachnoid Hemorrhage/diagnosis , Canada/epidemiology , Cohort Studies , Female , Humans , International Classification of Diseases , Male , Prognosis , Registries/statistics & numerical data , Reproducibility of Results , Sensitivity and Specificity , Subarachnoid Hemorrhage/classification , Subarachnoid Hemorrhage/epidemiology
5.
J Intellect Disabil Res ; 61(7): 719-725, 2017 07.
Article in English | MEDLINE | ID: mdl-28444813

ABSTRACT

BACKGROUND: Parents' positive and negative feelings about their young children influence both parenting behaviour and child problem behaviour. Research has not previously examined factors that contribute to positive and negative feelings in parents of young children with developmental delay (DD). METHOD: The present study sought to examine whether optimism, a known protective factor for parents of children with DD, was predictive of positive and negative feelings for these parents. Data were collected from 119 parents of preschool-aged children with developmental delay. Two separate hierarchical linear regression analyses were conducted to determine if optimism significantly predicted positive feelings and negative feelings and whether optimism moderated relations between parenting stress and parent feelings. RESULTS: Increased optimism was found to predict increased positive feelings and decreased negative feelings after controlling for child problem behaviour and parenting stress. In addition, optimism was found to moderate the relation between parenting stress and positive feelings. CONCLUSION: Results suggest that optimism may impact how parents perceive their children with DD. Future research should examine how positive and negative feelings impact positive parenting behaviour and the trajectory of problem behaviour specifically for children with DD.


Subject(s)
Child Behavior/psychology , Developmental Disabilities/psychology , Emotions , Optimism/psychology , Parenting/psychology , Parents/psychology , Problem Behavior/psychology , Adult , Child, Preschool , Female , Humans , Male
6.
Intensive care med ; 43(3)Mar. 2017.
Article in English | BIGG - GRADE guidelines | ID: biblio-948600

ABSTRACT

OBJECTIVE: To provide an update to "Surviving Sepsis Campaign Guidelines for Management of Sepsis and Septic Shock: 2012". DESIGN: A consensus committee of 55 international experts representing 25 international organizations was convened. Nominal groups were assembled at key international meetings (for those committee members attending the conference). A formal conflict-of-interest (COI) policy wasdeveloped at the onset of the process and enforced throughout. A stand-alone meeting was held for all panel members in December 2015. Teleconferences and electronic-based discussion among subgroupsand among the entire committee served as an integral part of the development. METHODS: The panel consisted of five sections: hemodynamics, infection, adjunctive therapies, metabolic, and ventilation. Population, intervention, comparison, and outcomes (PICO) questions were reviewed and updated as needed, and evidence profiles were generated. Each subgroup generated a list of questions, searched for best available evidence, and then followed the principles of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system to assess the quality of evidence from high to very low, and to formulate recommendations as strong or weak, or best practice statement when applicable. RESULTS: The Surviving Sepsis Guideline panel provided 93 statements on early management and resuscitation of patients with sepsis or septic shock. Overall, 32 were strong recommendations, 39 were weak recommendations, and 18 were best-practice statements. No recommendation was provided for four questions. CONCLUSIONS: Substantial agreement exists among a large cohort of international experts regarding many strong recommendations for the best care of patients with sepsis. Although a significant number of aspects of care have relatively weak support, evidence-based recommendations regarding the acute management of sepsis and septic shock are the foundation of improved outcomes for these critically ill patients with high mortality.(AU)


Subject(s)
Humans , Shock, Septic/drug therapy , Sepsis/drug therapy , Patient Care Planning , Respiration, Artificial , Vasoconstrictor Agents/therapeutic use , Calcitonin/therapeutic use , Nutrition Assessment , Chronic Disease/drug therapy , Renal Replacement Therapy , Fluid Therapy/methods , Anti-Bacterial Agents/administration & dosage
7.
BMJ Open ; 6(12): e012623, 2016 12 07.
Article in English | MEDLINE | ID: mdl-27927658

ABSTRACT

INTRODUCTION: Anaemia is common in aneurysmal subarachnoid haemorrhage (aSAH) and is a potential critical modifiable factor affecting secondary injury. Despite physiological evidence and management guidelines that support maintaining a higher haemoglobin level in patients with aSAH, current practice is one of a more restrictive approach to transfusion. The goal of this multicentre pilot trial is to determine the feasibility of successfully conducting a red blood cell (RBC) transfusion trial in adult patients with acute aSAH and anaemia (Hb ≤100 g/L), comparing a liberal transfusion strategy (Hb ≤100 g/L) with a restrictive strategy (Hb ≤80 g/L) on the combined rate of death and severe disability at 12 months. METHODS: Design This is a multicentre open-label randomised controlled pilot trial at 5 academic tertiary care centres. Population We are targeting adult aSAH patients within 14 days of their initial bleed and with anaemia (Hb ≤110 g/L). Randomisation Central computer-generated randomisation, stratified by centre, will be undertaken from the host centre. Randomisation into 1 of the 2 treatment arms will occur when the haemoglobin levels of eligible patients fall to ≤100 g/L. Intervention Patients will be randomly assigned to either a liberal (threshold: Hb ≤100 g/L) or a restrictive transfusion strategy (threshold: Hb ≤80 g/L). Outcome Primary: Centre randomisation rate over the study period. Secondary: (1) transfusion threshold adherence; (2) study RBC transfusion protocol adherence; and (3) outcome assessment including vital status at hospital discharge, modified Rankin Score at 6 and 12 months and Functional Independence Measure and EuroQOL Quality of Life Scale scores at 12 months. Outcome measures will be reported in aggregate. ETHICS AND DISSEMINATION: The study protocol has been approved by the host centre (OHSN-REB 20150433-01H). This study will determine the feasibility of conducting the large pragmatic RCT comparing 2 RBC transfusion strategies examining the effect of a liberal strategy on 12-month outcome following aSAH. TRIAL REGISTRATION NUMBER: NCT02483351; Pre-results.


Subject(s)
Critical Care , Endovascular Procedures/methods , Erythrocyte Transfusion , Subarachnoid Hemorrhage/therapy , Anemia/mortality , Clinical Protocols , Disability Evaluation , Endovascular Procedures/mortality , Erythrocyte Transfusion/methods , Erythrocyte Transfusion/mortality , Feasibility Studies , Female , Humans , Male , North America/epidemiology , Outcome Assessment, Health Care , Pilot Projects , Quality of Life , Risk Factors , Subarachnoid Hemorrhage/mortality , Subarachnoid Hemorrhage/physiopathology , Treatment Outcome
8.
Nat Commun ; 7: 11711, 2016 05 23.
Article in English | MEDLINE | ID: mdl-27210515

ABSTRACT

Metallic transition-metal dichalcogenides (TMDCs) are benchmark systems for studying and controlling intertwined electronic orders in solids, with superconductivity developing from a charge-density wave state. The interplay between such phases is thought to play a critical role in the unconventional superconductivity of cuprates, Fe-based and heavy-fermion systems, yet even for the more moderately-correlated TMDCs, their nature and origins have proved controversial. Here, we study a prototypical example, 2H-NbSe2, by spin- and angle-resolved photoemission and first-principles theory. We find that the normal state, from which its hallmark collective phases emerge, is characterized by quasiparticles whose spin is locked to their valley pseudospin. This results from a combination of strong spin-orbit interactions and local inversion symmetry breaking, while interlayer coupling further drives a rich three-dimensional momentum dependence of the underlying Fermi-surface spin texture. These findings necessitate a re-investigation of the nature of charge order and superconducting pairing in NbSe2 and related TMDCs.

9.
Sci Rep ; 6: 26549, 2016 05 25.
Article in English | MEDLINE | ID: mdl-27221782

ABSTRACT

We present a study of the structure and chemical composition of the Cr-doped 3D topological insulator Bi2Se3. Single-crystalline thin films were grown by molecular beam epitaxy on Al2O3 (0001), and their structural and chemical properties determined on an atomic level by aberration-corrected scanning transmission electron microscopy and electron energy loss spectroscopy. A regular quintuple layer stacking of the Bi2Se3 film is found, with the exception of the first several atomic layers in the initial growth. The spectroscopy data gives direct evidence that Cr is preferentially substituting for Bi in the Bi2Se3 host. We also show that Cr has a tendency to segregate at internal grain boundaries of the Bi2Se3 film.

10.
Sci Rep ; 5: 15767, 2015 Oct 27.
Article in English | MEDLINE | ID: mdl-26503435

ABSTRACT

The breaking of time reversal symmetry (TRS) in three-dimensional (3D) topological insulators (TIs), and thus the opening of a 'Dirac-mass gap' in the linearly dispersed Dirac surface state, is a prerequisite for unlocking exotic physical states. Introducing ferromagnetic long-range order by transition metal doping has been shown to break TRS. Here, we present the study of lanthanide (Ln) doped Bi2Te3, where the magnetic doping with high-moment lanthanides promises large energy gaps. Using molecular beam epitaxy, single-crystalline, rhombohedral thin films with Ln concentrations of up to ~35%, substituting on Bi sites, were achieved for Dy, Gd, and Ho doping. Angle-resolved photoemission spectroscopy shows the characteristic Dirac cone for Gd and Ho doping. In contrast, for Dy doping above a critical doping concentration, a gap opening is observed via the decreased spectral intensity at the Dirac point, indicating a topological quantum phase transition persisting up to room-temperature.

11.
J Phys Condens Matter ; 27(24): 245602, 2015 Jun 24.
Article in English | MEDLINE | ID: mdl-26000785

ABSTRACT

Breaking the time-reversal symmetry (TRS) in topological insulators (TIs) through ferromagnetic doping is an essential prerequisite for unlocking novel physical phenomena and exploring potential device applications. Here, we report the successful growth of high-quality (Dy(x)Bi(1-x))2Te3 thin films with Dy concentrations up to x = 0.355 by molecular beam epitaxy. Bulk-sensitive magnetisation studies using superconducting quantum interference device magnetometry find paramagnetic behaviour down to 2 K for the entire doping series. The effective magnetic moment, µeff, is strongly doping concentration-dependent and reduces from ∼12.6 µ(B) Dy(-1) for x = 0.023 to ∼4.3 µ(B) Dy(-1) for x = 0.355. X-ray absorption spectra and x-ray magnetic circular dichroism (XMCD) at the Dy M4,5 edge are employed to provide a deeper insight into the magnetic nature of the Dy(3+)-doped films. XMCD, measured in surface-sensitive total-electron-yield detection, gives µ(eff )= 4.2 µ(B) Dy(-1). The large measured moments make Dy-doped films interesting TI systems in which the TRS may be broken via the proximity effect due to an adjacent ferromagnetic insulator.

12.
Sci Rep ; 5: 7907, 2015 Jan 20.
Article in English | MEDLINE | ID: mdl-25601364

ABSTRACT

Topological insulators (TIs) are enticing prospects for the future of spintronics due to their large spin-orbit coupling and dissipationless, counter-propagating conduction channels in the surface state. However, a means to interact with and exploit the topological surface state remains elusive. Here, we report a study of spin pumping at the TI-ferromagnet interface, investigating spin transfer dynamics in a spin-valve like structure using element specific time-resolved x-ray magnetic circular dichroism, and ferromagnetic resonance. Gilbert damping increases approximately linearly with increasing TI thickness, indicating efficient behaviour as a spin sink. However, layer-resolved measurements suggest that a dynamic coupling is limited. These results shed new light on the spin dynamics of this novel material class, and suggest great potential for TIs in spintronic devices, through their novel magnetodynamics that persist even up to room temperature.

14.
N Z Vet J ; 62(6): 343-50, 2014 Nov.
Article in English | MEDLINE | ID: mdl-24961961

ABSTRACT

AIMS: To estimate the number of cases of scrapie that would occur in sheep of different prion protein (PrP) genotypes if scrapie was to become established in New Zealand, and to compare the performance of two commercially available, rapid ELISA kits using ovine retro-pharyngeal lymph nodes (RLN) from non-infected and infected sheep of different PrP genotypes. METHODS: Using published data on the distribution of PrP genotypes within the New Zealand sheep flock and the prevalence of cases of scrapie in these genotypes in the United Kingdom, the annual expected number of cases of scrapie per genotype was estimated, should scrapie become established in New Zealand, assuming a total population of 28 million sheep. A non-infected panel of RLN was collected from 737 sheep from New Zealand that had been culled, found in extremis or died. Brain stem samples were also collected from 131 of these sheep. A second panel of infected samples comprised 218 and 117 RLN from confirmed scrapie cases that had originated in Europe and the United States of America, respectively. All samples were screened using two commercial, rapid, transmissible spongiform encephalopathy ELISA kits: Bio-Rad TeSeE ELISA (ELISA-BR), and IDEXX HerdChek BSE-Scrapie AG Test (ELISA-ID). RESULTS: If scrapie became established in New Zealand, an estimated 596 cases would occur per year; of these 234 (39%) and 271 (46%) would be in sheep carrying ARQ/ARQ and ARQ/VRQ PrP genotypes, respectively. For the non-infected samples from New Zealand the diagnostic specificity of both ELISA kits was 100%. When considering all infected samples, the diagnostic sensitivity was 70.4 (95% CI=65.3-75.3)% for ELISA-BR and 91.6 (95% CI=88.2-94.4)% for ELISA-ID. For the ARQ/ARQ genotype (n=195), sensitivity was 66.2% for ELISA-BR and 90.8% for ELISA-ID, and for the ARQ/VRQ genotype (n=107), sensitivity was 81.3% for ELISA-BR and 98.1% for ELISA-ID. CONCLUSIONS: In this study, the ELISA-ID kit demonstrated a higher diagnostic sensitivity for detecting scrapie in samples of RLN from sheep carrying scrapie-susceptible PrP genotypes than the ELISA-BR kit at comparable diagnostic specificity. CLINICAL RELEVANCE: The diagnostic performance of the ELISA-ID kit using ovine RLN merits the consideration of including this assay in the national scrapie surveillance programme in New Zealand.


Subject(s)
Enzyme-Linked Immunosorbent Assay/veterinary , Lymph Nodes/pathology , Reagent Kits, Diagnostic/veterinary , Scrapie/diagnosis , Animals , Enzyme-Linked Immunosorbent Assay/methods , Prions/genetics , Sensitivity and Specificity , Sheep
15.
Int J Public Health ; 59(1): 3-14, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24381979

ABSTRACT

OBJECTIVES: Unintended harm theory as related to public health interventions (PHI) is under developed, with harm evaluation and reporting often absent or incomplete. This review presents a typology for, and underlying factors linked to, PHI-associated unintended harm. METHODS: This scoping review was conducted electronically and includes articles from 1992 to June of 2013. Out of 2,490 originally identified titles, 26 full-text articles were included that discussed unintended harm associated with PHI. An iterative data analysis process was utilized to identify both a typology and underlying factors associated with unintended harm. RESULTS: A typology of PHI-associated unintended harm was identified: (1) physical; (2) psychosocial; (3) economic; (4) cultural and (5) environmental. Five underlying factors associated with PHI unintended harm emerged: (1) limited and/or poor quality evidence; (2) prevention of one extreme leads to another (boomerang effects); (3) lack of community engagement; (4) ignoring root causes; and (5) higher-income country PHI implementation in a lower- or middle-income country. CONCLUSIONS: PHI planning and evaluation frameworks may benefit from the consideration and potential incorporation of the unintended harm typology and underlying factors.


Subject(s)
Health Promotion , Public Health Practice , Safety , Humans , Models, Theoretical , Risk Assessment
17.
J Appl Microbiol ; 115(6): 1427-38, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23957554

ABSTRACT

AIM: To isolate and characterize listeriaphages from seafood environments. METHODS AND  RESULTS: Listeriaphages (phages) isolated from seafood environments were distinguished by physical and biological techniques including restriction digestion of phage DNA. Three phages belonged to order Caudovirales and showed psychrotrophic characteristics. The phages had broad host ranges against 23 Listeria strains by productive infection or at least by adsorption. At 15 ± 1°C, adsorption rate constants of the three phages ranged from 8·93 × 10(-9) to 3·24 × 10(-11 ) ml min(-1) across different Listeria monocytogenes strains. In indicator hosts, the mean burst sizes of phages LiMN4L, LiMN4p and LiMN17 were c. 17, 17 and 11 plaque-forming units (PFU) per cell, respectively, at 15 ± 1°C. The respective latent periods were c. 270 min for phages LiMN4p and LiMN17, whereas for phage LiMN4L, it was c. 240 min. CONCLUSIONS: The three virulent psychrotrophic phages isolated from seafood-processing environments had broad host ranges and low productive replication. These characteristics suggest that the phages may be suitable as passive biocontrol agents against seafood-borne L. monocytogenes. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report on the isolation of autochthonous virulent listeriaphages from seafood-processing environments and information on single-step replication and adsorption characteristics of such listeriaphages.

18.
Sci Rep ; 3: 2087, 2013.
Article in English | MEDLINE | ID: mdl-23804036

ABSTRACT

Magnetoresistance (MR) effects are at the heart of modern information technology. However, future progress of giant and tunnelling MR based storage and logic devices is limited by the usable MR ratios of currently about 200% at room-temperature. Colossal MR structures, on the other hand, achieve their high MR ratios of up to 10(6)% only at low temperatures and high magnetic fields. We introduce the extraordinary Hall balance (EHB) and demonstrate room-temperature MR ratios in excess of 31,000%. The new device concept exploits the extraordinary Hall effect in two separated ferromagnetic layers with perpendicular anisotropy in which the Hall voltages can be configured to be carefully balanced or tipped out of balance. Reprogrammable logic and memory is realised using a single EHB element. PACS numbers: 85.75.Nn,85.70.Kh,72.15.Gd,75.60.Ej.

19.
Transfus Med ; 23(2): 94-9, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23448208

ABSTRACT

BACKGROUND: Red blood cell transfusion has been associated with adverse outcomes including infection, delayed recovery and increased mortality in some patient populations. Circulating cells that yield endothelial-like vascular progenitor cell (VPC) clusters are correlated with vascular repair and recovery after ischaemic injury. The impact of red cell transfusion on VPC clusters and vascular repair remains uncertain. STUDY DESIGN: We prospectively enrolled patients admitted to intensive care requiring red cell transfusion and subjects at low likelihood of requiring red cell transfusion. Levels of VPC clusters and plasma levels of angiogenic cytokines were compared. A total of 17 patients were recruited and had blood samples collected at time of enrolment and at 24-48 h, 48-72 h and 1 week following transfusion. RESULTS: We could not discern differences in the number of VPC clusters between transfused patients (n = 6) and non-transfused subjects (n = 11) at baseline or throughout the study period. VPC cluster levels demonstrated wide variance and were highest at 24-h post-enrolment in the entire cohort. Furthermore, levels of all 16 cytokines analysed were not significantly different between transfused and non-transfused patients and we did not observe a correlation between cytokine concentrations and levels of circulating VPC-cluster forming cells in the overall study population. CONCLUSIONS: Our data suggest that assessment of vascular repair responses after red blood cell transfusion in critically ill patients is challenging. Although our study did not allow us to discern an influence of red cell transfusion on VPC cluster levels or angiogenic cytokines, new methods evaluating vascular repair mechanisms may be required.


Subject(s)
Angiogenesis Inducing Agents/blood , Cytokines/blood , Endothelial Cells/cytology , Erythrocyte Transfusion , Regeneration , Stem Cells/cytology , Critical Illness , Female , Humans , Male , Middle Aged , Pilot Projects , Prospective Studies
20.
Eur J Neurol ; 20(3): 448-452, 2013 Mar.
Article in English | MEDLINE | ID: mdl-22816507

ABSTRACT

BACKGROUND AND PURPOSE: To evaluate a dipstick algorithm for urinary tract colonization, prior to high-dose corticosteroid treatment in acute relapses of multiple sclerosis (MS). METHODS: Prospective cohort study of 267 consecutive patients with MS relapses requiring corticosteroid treatment in a hospital-based, ambulatory, acute MS relapse clinic. A total of 18 participants met the exclusion criteria, leaving 249 for analysis. Main outcome measures were urinary dipstick sensitivity, specificity, positive predictive value, negative predictive value and safety of antibiotic co-treatment with high-dose corticosteroids. RESULTS: Significant bacteriuria (≥10(5) colonies ml) rate in this population was 11% (95% CI, 7.1-14.9). Specificity and sensitivity of positive leucocyte esterase or nitrite were 78% and 65%. Negative predictive value of urine dipstick was 96%. No clinical adverse events occurred in the 3% (95% CI, 0.9-5.1) of patients with a false-negative dipstick. Eighteen per cent of patients were unnecessarily treated with antibiotics for 48 h. CONCLUSION: Urinary dipstick testing allows for rapid and safe management of patients suffering from an acute MS relapse. The algorithm is conservative, and future work is needed to reduce the false-positive rate.


Subject(s)
Adrenal Cortex Hormones/therapeutic use , Algorithms , Bacteriuria/urine , Multiple Sclerosis, Relapsing-Remitting/drug therapy , Multiple Sclerosis, Relapsing-Remitting/urine , Adult , Bacteriuria/complications , Bacteriuria/diagnosis , Female , Humans , Male , Multiple Sclerosis, Relapsing-Remitting/complications , Sensitivity and Specificity
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