Colossal Tunneling Electroresistance in Co-Planar Polymer Ferroelectric Tunnel Junctions

Ferroelectric tunnel junctions (FTJs) are ideal resistance-switching devices due to their deterministic behavior and operation at low voltages. However, FTJs have remained mostly as a scientific curiosity due to three critical issues: lack of rectification in their current-voltage characteristic, small tunneling electroresistance (TER) effect, and absence of a straightforward lithography-based device fabrication method that would allow for their mass production. Co-planar FTJs that are fabricated using wafer-scale adhesion lithography technique are demonstrated, and a bi-stable rectifying behavior with colossal TER approaching 106% at room temperature is exhibited. The FTJs are based on poly(vinylidenefluoride-co-trifluoroethylene) [P(VDF-TrFE)], and employ asymmetric co-planar metallic electrodes separated by &lt;20 nm. The tunneling nature of the charge transport is corroborated using Simmons direct tunneling model. The present work is the first demonstration of functional FTJs manufactured via a scalable lithography-based nano-patterning technique and could pave the way to new and exciting memory device concepts.</p

Classification of children as slow or rapid acetylators based on concentrations of isoniazid in saliva folowing oral administration of body-weight and surface-area-related dosages of the drug

The acetylator phenotype of 180 children aged 3-11 years was determined on the basis of isoniazid concentrations in saliva collected at 5 hours after oral administration of body-weight and surfacearea- related &sages of the drug in a syrup form. isoniazid 25 mglkg was administered on one occasion and 75 mg/m2 surface-area on another, with an interval of 3 days between the occasions. A cross-over design was employed and the sequence was determined by random allocation. The distribution of the concentrations was bimodal with both procedures, indicating the presence of two groups namely, the slow and rapid acetylators. The criterion for a rapid acetylator was a concentration of 0.3 μg/ml or less by body-weight-related dosage and 0.4 μg/ml or less by that based on surface-area. Based on these criteria, 62 % of the children were classified as slow acetylators and 38% as rapid acetylators by body-weight, and 59 and 41 %, respectively by surface-area, and the findings were similar in children in the different age-groups. The agreement between the two procedures was 98%

Response to foot and mouth disease (FMD) vaccination among local Malaysian cattle of various vaccination backgrounds from endemic and non-endemic FMD areas

A longitudinal study assessed the response to foot and mouth disease virus (FMDV) vaccination on sequential sera of local Malaysian Kedah-Kelantan cattle in two states of Peninsular Malaysia; Perlis, a foot and mouth (FMD) disease non-endemic state, and Kelantan, an endemic state for FMD. These cattle were from various vaccination backgrounds and some with unknown vaccination status. For the cattle in both states, the antibody against FMDV type O effectively increased to a strong protective level in the first week following vaccination, regardless of the vaccination background of the animals. In the endemic state, where vaccination was performed more routinely than the non-endemic state, the response had better magnitude and duration. In the non-endemic state, the antibody response level was good but appeared to last for a shorter period of time before it significantly declined. For naïve cattle with no evidence of infection or vaccination, the response was rapid and reached a strong level immediately by the first week. However, the level was not sustained and significantly declined thereafter. All the cattle stayed healthy and clinically FMD- free throughout the study, even when there was a transient evidence of natural field infection detected among the cattle. A marked difference was observed in the patterns of antibody response between cattle in the FMD endemic and non-endemic areas. However, the level of antibodies generally rose to a strong protective level within the stipulated 7-14 days post-vaccination. The vaccine used was effective in eliciting immune response when naturally challenged by the local field FMD virus

Anomalous metamagnetism in the low carrier density Kondo lattice YbRh3Si7

We report complex metamagnetic transitions in single crystals of the new low carrier Kondo antiferromagnet YbRh3Si7. Electrical transport, magnetization, and specific heat measurements reveal antiferromagnetic order at T_N = 7.5 K. Neutron diffraction measurements show that the magnetic ground state of YbRh3Si7 is a collinear antiferromagnet where the moments are aligned in the ab plane. With such an ordered state, no metamagnetic transitions are expected when a magnetic field is applied along the c axis. It is therefore surprising that high field magnetization, torque, and resistivity measurements with H||c reveal two metamagnetic transitions at mu_0H_1 = 6.7 T and mu_0H_2 = 21 T. When the field is tilted away from the c axis, towards the ab plane, both metamagnetic transitions are shifted to higher fields. The first metamagnetic transition leads to an abrupt increase in the electrical resistivity, while the second transition is accompanied by a dramatic reduction in the electrical resistivity. Thus, the magnetic and electronic degrees of freedom in YbRh3Si7 are strongly coupled. We discuss the origin of the anomalous metamagnetism and conclude that it is related to competition between crystal electric field anisotropy and anisotropic exchange interactions.Comment: 23 pages and 4 figures in the main text. 7 pages and 5 figures in the supplementary materia

Assessing the Potential Risk Factors for Patients with Brain Stroke: A Retrospective Study

The primary cause of impairment is stroke. When you factor in cancer and coronary heart disease, it is the third most common cause of death. It has a significant global impact on public health. The estimated five million stroke-related fatalities globally are expected to double due to anticipated significant changes in demographics and lifestyle, such as rising rates of obesity, diabetes mellitus, smoking, and hypertension. This study traced the risk factors of brain stroke patients using the Kaggle search engine dataset, which comprised the medical records of 201 people with the condition. The mortality was modelled using the Cox regression approach, which took into consideration the observed covariates. It was determined that five variables significantly increased the incidence of brain stroke in patients.&nbsp

Low-carrier density and fragile magnetism in a Kondo lattice system

Kondo-based semimetals and semiconductors are of extensive current interest as a viable platform for strongly correlated states. It is thus important to understand the routes towards such dilute-carrier correlated states. One established pathway is through Kondo effect in metallic non-magnetic analogues. Here we advance a new mechanism, through which Kondo-based semimetals develop out of conduction electrons with a low carrier-density in the presence of an even number of rare-earth sites. We demonstrate this effect by studying the Kondo material Yb3Ir4Ge13 along with its closed-f-shell counterpart, Lu3Ir4Ge13. Through magnetotransport, optical conductivity and thermodynamic measurements, we establish that the correlated semimetallic state of Yb3Ir4Ge13 below its Kondo temperature originates from the Kondo effect of a low carrier conduction-electron background. In addition, it displays fragile magnetism at very low temperatures, which, in turn, can be tuned to a non Fermi liquid regime through Lu-for-Yb substitution. These findings are connected with recent theoretical studies in simplified models. Our results open an entirely new venue to explore the strong correlation physics in a semimetallic environment

Real-Life Anti-Tumour Necrosis Factor Experience in > 500 Paediatric United Kingdom Inflammatory Bowel Disease Patients.

OBJECTIVES: To measure the effectiveness, safety and use of anti-Tumour necrosis Factor (TNF) therapy in paediatric inflammatory bowel disease (PIBD) in the United Kingdom (UK). METHODS: Prospective UK audit of patients newly starting anti-TNF therapy. Disease severity was assessed using Physician Global Assessment (PGA) +/or the Paediatric Crohn's Disease Activity Index (PCDAI). RESULTS: 37 centres participated (23 of 25 specialist PIBD sites). 524 patients were included; 429 Crohn's disease (CD), 76 ulcerative colitis (UC), 19 IBD unclassified (IBDU). 87% (488/562) anti-TNF was infliximab; commonest indication was active luminal CD 77% (330/429) or chronic refractory UC/IBDU 56% (53/95); 79% (445/562) had concomitant co-immunosuppression. In CD (267/429 male), median time from diagnosis to treatment was 1.42 years (IQR 0.63-2.97). Disease (at initiation) was moderate or severe in 91% (156/171) by PGA compared to 41% (88/217) by PCDAI; Kappa (Κ) 0.28 = only 'fair agreement' (p < 0.001).Where documented, 77% (53/69) of CD patients responded to induction; and 65% (46/71) entered remission. 2287 infusions and 301.96 years of patient follow-up (n = 385) are represented; adverse events affected 3% (49/1587) infliximab and 2% (2/98) adalimumab infusions (no deaths or malignancies). Perianal abscess drainage was less common after anti-TNF initiation (CD): 26% (27/102) before, 7% (3/42) after (p = 0.01); however pre and post anti-TNF data collection was not over equal time periods. CONCLUSION: Anti-TNFs are effective treatments, usually given with thiopurine co-immunosuppression. This study highlights deficiencies in formal documentation of effect and disparity between disease severity scoring tools which need to be addressed to improve ongoing patient care

Sorption-Desorption Behavior of Atrazine on Soils Subjected to Different Organic Long-Term Amendments

Sorption of atrazine on soils subjected to three different organic amendments was measured using a batch equilibrium technique. A higher K(F) value (2.20 kg(-1)(mg L(-1))(-)N) was obtained for soil fertilized with compost, which had a higher organic matter (OM) content. A correlation between the K(Foc) values and the percentage of aromatic carbon in OM was observed. The highest K(Foc) value was obtained for the soil with the highest aromatic content. Higher aromatic content results in higher hydrophobicity of OM, and hydrophobic interactions play a key role in binding of atrazine, On the other hand, the soil amended with farmyard manure had a higher content of carboxylic units, which could be responsible for hydrogen bonding between atrazine and OR Dominance of hydrogen bonds compared to hydrophobic interactions can be responsible for the lower desorption capacity observed with the farmyard manure soil, The stronger hydrogen bonding can reduce the leaching of atrazine into drinking water resources and runoff to rivers and other surface waters

Household catastrophic healthcare expenditure and impoverishment due to rotavirus gastroenteritis requiring hospitalization in Malaysia.

BACKGROUND: While healthcare costs for rotavirus gastroenteritis requiring hospitalization may be burdensome on households in Malaysia, exploration on the distribution and catastrophic impact of these expenses on households are lacking. OBJECTIVES: We assessed the economic burden, levels and distribution of catastrophic healthcare expenditure, the poverty impact on households and inequities related to healthcare payments for acute gastroenteritis requiring hospitalization in Malaysia. METHODS: A two-year prospective, hospital-based study was conducted from 2008 to 2010 in an urban (Kuala Lumpur) and rural (Kuala Terengganu) setting in Malaysia. All children under the age of 5 years admitted for acute gastroenteritis were included. Patients were screened for rotavirus and information on healthcare expenditure was obtained. RESULTS: Of the 658 stool samples collected at both centers, 248 (38%) were positive for rotavirus. Direct and indirect costs incurred were significantly higher in Kuala Lumpur compared with Kuala Terengganu (US$222 Vs. US$45; p<0.001). The mean direct and indirect costs for rotavirus gastroenteritis consisted 20% of monthly household income in Kuala Lumpur, as compared with only 5% in Kuala Terengganu. Direct medical costs paid out-of-pocket caused 141 (33%) households in Kuala Lumpur to experience catastrophic expenditure and 11 (3%) households to incur poverty. However in Kuala Terengganu, only one household (0.5%) experienced catastrophic healthcare expenditure and none were impoverished. The lowest income quintile in Kuala Lumpur was more likely to experience catastrophic payments compared to the highest quintile (87% vs 8%). The concentration index for out-of-pocket healthcare payments was closer to zero at Kuala Lumpur (0.03) than at Kuala Terengganu (0.24). CONCLUSIONS: While urban households were wealthier, healthcare expenditure due to gastroenteritis had more catastrophic and poverty impact on the urban poor. Universal rotavirus vaccination would reduce both disease burden and health inequities in Malaysia