N-Channel organic thin-film transistors based on naphthalene- bis(dicarboximide) polymer for organic transistor memory using hole-acceptor layer

An investigation of threshold voltage shifts in organic thin-film transistors (OTFTs) based on poly{[N,N″-bis(2-octyldodecyl)-naphthalene-1, 4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5″-(2,20-bithiophene)} [P(NDI2OD-T2)] with additional poly(3-hexylthiophene) (P3HT) films on a poly(methyl methacrylate) (PMMA) organic dielectric layer is reported. With a top source-drain contact structure, the device exhibited a unipolar property with n-channel characteristics similar to those of the P(NDI2OD-T2)-only device. Furthermore, the existence of P3HT films as hole acceptor-like storage layers resulted in reversible V th shift upon the application of external gate bias (V bias) for a certain bias time (T bias). Hence, the P(NDI2ODT2)/ P3HT-OTFTs exhibited a large memory window (δV th = 10.7 V) for write and erase electrically without major degradation in saturation mobility [μ sat = (1.8-2.8) × 10 ¯� cm 2 V ¯¹ s ¯¹]. These results clearly indicate the utility of the naphthalene-bis(dicarboximide) (NDI)-based polymer-hole acceptor layer in the development of n-channel organic transistor memories

Differences in the Composition of Activated Partial Thromboplastin Time (APTT) Reagents Affect Clot Waveform Analysis

Background Clot waveform analysis (CWA) based on activated partial thromboplastin time (APTT) is a useful assay for hemostasis. However, the effects of activators and phospholipid conditions on CWA have not been adequately investigated. Therefore, we characterized CWA using four different APTT reagents. Methods: We used 39 archived plasma samples from patients with hemophilia A (HA), 16 samples from patients with HA under emicizumab treatment, and 10 samples from healthy individuals for CWA with four different types of APTT reagents (reagents A, B, C, and D). We then compared Ad|min1|, Ad|min2|, and Ad|max2| from the CWA, which reflect the maximum velocity, maximum acceleration, and maximum deceleration, respectively, among the four reagents. Results: Similar clot waveform shapes were observed for each reagent in the healthy donor group, HA group, and HA under emicizumab group, and the waveform was different for each target group. Significant changes were found in clotting time (CT) (s), Ad|min1| (%/s), Ad|min2| (%/s2), and Ad|max2| (%/s2). The waveform pattern for the coagulation reaction by reagent D, comprising silica and synthetic phospholipids, was the fastest among the reagents examined. Further, the difference in Ad|min1| (%/s) and Ad|min2| (%/s2) was larger than that in CT depending on the reagent used(s), indicating that the measured value of CWA was affected by the reagent composition. Conclusion: Our results showed a significant difference among reagents with varying composition and concentration; this was found to affect the parameters obtained from CWA. Thus, the differences between reagents hinder standardization of quantitative evaluation using these parameters; further, this highlights the necessity of understanding the characteristics of APTT reagents and determining the reference range in individual facilities

n-Channel Organic Thin-Film Transistors based on Naphthalene-Bis(dicarboximide) Polymer for Organic Transistor Memory Using Hole-Acceptor Layer

Organic semiconductors have been the subject of interest for the past decade. Despite significant progress in the p-channel organic thin-film transistors (OTFTs), there are still problems concerning the development of n-channel OTFTs owing to the selection of n-channel organic materials, which are limited to a very small number of molecules and polymers [1], and also serious drawbacks, including poor solubility, difficulty of synthesis and unstable transistor operation under ambient atmosphere [2]. Since the first air-stable n-channel OTFTs based on naphthalenetetracarboxylic diimides was reported [3], a large number of n-channel organic materials have been based on either naphthalene diimide (NDI) — or perylene diimide (PDI)-based polymers. It is therefore clear that n-channel organic materials have an important role in the continuing development of organic-based circuits and products. In this study, we focused to elucidate the fabrication and characterization of n-channel OTFTs based on poly{[N, N'bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5'-(2,2'-bithiophene)} [P(NDI2D-T2)]. Moreover, we also demonstrate organic transistor memory with an n-channel P(NDI2OD-T2) OTFTs using poly(3-hexylthiophene) (P3HT) as the charge trapping layer

Bias stress and memory effect in pentacene-based organic thin-film transistors with a fullerene layer

Organic memory-transistor devices were fabricated from pentacene-based organic thin-film transistors (OTFTs) with a fullerene layer. The current-voltage (I-V) characteristics show that the fabricated OTFTs exhibit a unipolar property with p-channel characteristics. The fabricated OTFTs devices exhibit a threshold voltage shift upon the application of positive and negative bias. Under the effect of positive bias, the on state was induced and a ΔVth = 12.9 V was obtained. Meanwhile, the threshold voltage was reversibly shifted by ΔVth = 9.1 V under the effect of negative bias and the off state was induced. Upon the effect of bias, the carrier mobility of fabricated OTFTs is almost similar in both on and off states. Pentacene-based OTFTs without a fullerene layer for memory effect was demonstrated for comparison. The memory effect is mainly attributed to the fullerene layer

Organic field-effect transistors with reversible threshold voltage shifts for memory element

We introduce an charge-accepting layer on a poly(methyl methacrylate) (PMMA) dielectric to investigate the reversible threshold voltage (V) shifts in all-polymer n-channel organic field-effect transistor (OFET) using an organic semiconductor of an poly{[N,N’-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5’-(2,2’-bithiophene)} (P(NDI2OD-T2)). Top contact drain-source with a bottom-gate contact structure device exhibited a unipolar property with n-channel behavior. Furthermore, the existence of poly(3-hexylthiophene) (P3HT) films as a charge-accepting-like storage layers resulted in a reversible Vth shifts upon the application of external gate bias (V). Hence, all-polymer organic transistor with the charge-accepting layer exhibited a large memory window (?V th bias = 10.7 V) for write and erase electrically without major degradation in saturation mobility (µsat =1.8~2.8×10-4 cm2V-1s-1)

Outcome of Allogeneic Hematopoietic Stem Cell Transplantation for Acute Myeloid Leukemia Patients with Central Nervous System Involvement

AbstractCentral nervous system (CNS) involvement in adult acute myeloid leukemia (AML) is rare and associated with poor outcomes. Therefore, CNS involvement in AML is an indicator for allogeneic hematopoietic stem cell transplantation (allo-HSCT). However, the impact of CNS involvement in AML on the outcome of allo-HSCT remains unclear. We performed a large-scale nationwide retrospective analysis to elucidate the outcomes of allo-HSCT on AML with CNS involvement (CNS+AML). Clinical data were collected from a registry database of the Japan Society for Hematopoietic Cell Transplantation. CNS involvement was defined as the infiltration of leukemia cells into the CNS or myeloid sarcoma in the CNS identified at any time from diagnosis to transplantation. One hundred fifty-seven patients with CNS+AML underwent allo-HSCT between 2006 and 2011. The estimated overall survival, cumulative incidence of relapse and nonrelapse mortality at 2 years for CNS+AML (51.2%, 30.2%, and 14.5%, respectively) were comparable with those for AML without CNS involvement (48.6%, 27.4%, and 22.0%, respectively). Univariate and multivariate analyses indicated that the development of chronic graft-versus-host disease, disease status, and cytogenetic risk category were independent prognostic factors for overall survival for CNS+AML. These results suggest that allo-HSCT may improve outcomes in patients with CNS+AML

Sequential star formation in a cometary globule (BRC37) of IC1396

We have carried out near-IR/optical observations to examine star formation toward a bright-rimmed cometary globule (BRC37) facing the exciting star(s) of an HII region (IC1396) containing an IRAS source, which is considered to be an intermediate-mass protostar. With slit-less spectroscopy we detected ten H_alpha emission stars around the globule, six of which are near the tip of the globule and are aligned along the direction to the exciting stars. There is evidence that this alignment was originally towards an O9.5 star, but has evolved to align towards a younger O6 star when that formed. Near-IR and optical photometry suggests that four of these six stars are low-mass young stellar objects (YSOs) with masses of ~0.4 M_sun. Their estimated ages of ~1 Myr indicate that they were formed at the tip in advance of the formation of the IRAS source. Therefore, it is likely that sequential star formation has been taking place along the direction from the exciting stars towards the IRAS source, due to the UV impact of the exciting star(s). Interestingly, one faint, H_alpha emission star, which is the closest to the exciting star(s), seems to be a young brown dwarf that was formed by the UV impact in advance of the formation of other YSOs at the tip.Comment: main text (30 pages) + online material, 14 figures, published in A

Intestinal Bacteria as Powerful Trapping Lifeforms for the Elimination of Radioactive Cesium

In March 2011, an accident at the Fukushima Daiichi Nuclear Power Plant led to major problems, including the release of radionuclides such as Cesium (Cs)-137 into the environment. Ever since this accident, Cs-137 in foods has become a serious problem. In this study, we determined the concentration of Cs-137 in the feces, urine, and ruminal contents of cattle and demonstrated the possibility of its elimination from the body by intestinal bacteria. The results revealed a high Cs-137 concentration in the feces; in fact, this concentration was higher than that in skeletal muscles and other samples from several animals. Furthermore, intestinal bacteria were able to trap Cs-137, showing an uptake ratio within the range of 38–81% in vitro. This uptake appeared to be mediated through the sodium–potassium (Na+-K+) ion pump in the bacterial cell membrane. This inference was drawn based on the fact that the uptake ratio of Cs-137 was decreased in media with high potassium concentration. In addition, it was demonstrated that intestinal bacteria hindered the trapping of Cs-137 by the animal. Cattle feces showed high concentration of Cs-137 and intestinal bacteria trapped Cs-137. This study is the first report showing that intestinal bacteria contribute to the elimination of Cs-137 from the body

Ectopic fat deposition and global cardiometabolic risk : New paradigm in cardiovascular medicine

The obesity epidemic is a global public health concern that increases the likelihood of morbidity and mortality of metabolic and cardiovascular disease (CVD) and threatens to reduce life expectancy around the world. The concept of the metabolic syndrome (MetS) takes into account that visceral fat plays an essential role in the development of metabolic and cardiovascular diseases. However, MetS cannot be used to assess global CVD risk but is at best one more modifiable CVD risk factor. Thus, global cardiometabolic risk (the global risk of cardiovascular disease resulting from traditional risk factors combined with the additional contribution of the metabolic syndrome and/or insulin resistance) should be considered individually. There is solid evidence supporting the notion that excess abdominal fat is predictive of insulin resistance and the presence of related metabolic abnormalities currently referred to as MetS. Despite the fact that abdominal obesity is a highly prevalent feature of MetS, the mechanisms by which abdominal obesity is causally related to MetS are not fully elucidated. Besides visceral fat accumulation, ectopic lipid deposition, especially in liver and skeletal muscle, has been implicated in the pathophysiology of diabetes, insulin resistance and obesity-related disorders. Also, ectopic fat deposition could be deteriorated in the heart components such as (1) circulatory and locally recruited fat, (2) intra- and extra-myocellular fat, (3) perivascular fat, and (4) pericardial fat. In this review, the contribution of ectopic lipid deposition to global cardiometabolic risk is reviewed and also discussed are potential underlying mechanisms including adipocytokine, insulin resistance and lipotoxicity