244 research outputs found
Low temperature atomic layer deposited ZnO photo thin film transistors
Cataloged from PDF version of article.ZnO thin film transistors (TFTs) are fabricated on Si substrates using atomic layer deposition technique. The growth temperature of ZnO channel layers are selected as 80, 100, 120, 130, and 250°C. Material characteristics of ZnO films are examined using x-ray photoelectron spectroscopy and x-ray diffraction methods. Stoichiometry analyses showed that the amount of both oxygen vacancies and interstitial zinc decrease with decreasing growth temperature. Electrical characteristics improve with decreasing growth temperature. Best results are obtained with ZnO channels deposited at 80°C; Ion/Ioff ratio is extracted as 7.8 × 109 and subthreshold slope is extracted as 0.116 V/dec. Flexible ZnO TFT devices are also fabricated using films grown at 80°C. ID-VGS characterization results showed that devices fabricated on different substrates (Si and polyethylene terephthalate) show similar electrical characteristics. Sub-bandgap photo sensing properties of ZnO based TFTs are investigated; it is shown that visible light absorption of ZnO based TFTs can be actively controlled by external gate bias. © 2014 American Vacuum Society
Reducing bias in auditory duration reproduction by integrating the reproduced signal
Duration estimation is known to be far from veridical and to differ for sensory estimates and motor reproduction. To investigate how these differential estimates are integrated for estimating or reproducing a duration and to examine sensorimotor biases in duration comparison and reproduction tasks, we compared estimation biases and variances among three different duration estimation tasks: perceptual comparison, motor reproduction, and auditory reproduction (i.e. a combined perceptual-motor task). We found consistent overestimation in both motor and perceptual-motor auditory reproduction tasks, and the least overestimation in the comparison task. More interestingly, compared to pure motor reproduction, the overestimation bias was reduced in the auditory reproduction task, due to the additional reproduced auditory signal. We further manipulated the signal-to-noise ratio (SNR) in the feedback/comparison tones to examine the changes in estimation biases and variances. Considering perceptual and motor biases as two independent components, we applied the reliability-based model, which successfully predicted the biases in auditory reproduction. Our findings thus provide behavioral evidence of how the brain combines motor and perceptual information together to reduce duration estimation biases and improve estimation reliability
Određivanje aflatoksina, okratoksina A, fumonizina i zearalenona u žitaricama i krmivu primjenom kompetetivnoga direktnog imunoenzimatskog testa (CD-ELISA) i tankoslojne kromatografije (TLC)
Aspergillus, Penicillium, and Fusarium species frequently contaminate crops. For this reason mycotoxins such as afl atoxins (AFs), ochratoxin A (OTA), fumonisins (FBs), and zearalenone (ZEA) are found in food and feed in a wide range of concentrations, depending on environmental and storage conditions.
Consumption of mycotoxin-contaminated food and feed has been associated with acute and chronic poisoning and carcinoma. The aim of this study was to determine the incidence and co-occurrence of AFs
(B1+B2+G1+G2), OTA, FBs (B1+B2+B3), and ZEA in 37 samples of cereals and feed randomly collected in 2007 from households of an endemic nephropathy (EN) area in Croatia. The mycotoxins were determined using the competitive direct ELISA test (CD-ELISA) in combination with thin-layer chromatography (TLC). The most frequent mycotoxin was ZEA (92 %, mean 318.3 μg kg-1), followed by FBs (27 %, 3690 μg kg-1), AFs (24.3 %, 4.6 μg kg-1), and OTA (16.2 %, 9.8 μg kg-1). Levels of AFs, ZEA, and FBs detected by CD-ELISA signifi cantly correlated with the TLC results. However, only one OTA-positive sample was confi rmed by TLC due to its high limit of detection. The levels of these mycotoxins were below the permissible limit for animal feed. Twenty-nine percent of cereals were contaminated with FBs, OTA, or ZEA in mass fractions above the permissible limit for humans. Co-occurrence of two toxins
varied between 4.2 % and 54 % and of three between 4.2 % and 7.6 %. Prolonged co-exposure to AFs, OTA, FBs, and ZEA might increase the risk of various chronic diseases.Vrste plijesni iz rodova Aspergillus, Penicillium i Fusarium česti su kontaminanti usjeva te na takvim supstratima tvore mikotoksine. Stoga su žitarice i krmiva često kontaminirana afl atoksinima (AFs),
okratoksinom A (OTA), fumonizinima (FBs) i zearalenonom (ZEA) u različitim koncentracijama ovisno o mikroklimatskim uvjetima na polju i u skladištu. Konzumiranje hrane kontaminirane mikotoksinima
često je povezano s akutnim ili kroničnim trovanjima, ali i s razvojem karcinoma. Cilj ovog rada bio je odrediti istodobnu pojavnost AFs (B1+B2+G1+G2), OTA, FBs (B1+B2+B3) i ZEA u uzorcima žitarica i krme (N=37) koji su nasumično skupljeni u individualnim domaćinstvima na području endemske nefropatije (EN) u Hrvatskoj (2007). Za određivanje navedenih mikotoksina korišten je kompetitivni direktni ELISA-test (CD-ELISA) u kombinaciji s tankoslojnom kromatografi jom (TLC). Najzastupljeniji mikotoksin bio
je ZEA (92 %, srednja koncentracija 318.3 μg kg-1), nakon čega slijede FBs (27 %, 3690 μg kg-1), AFs (24.3 %, 4.6 μg kg-1) te OTA (16.2 %, 9.8 μg kg-1). Koncentracije AFs, FBs i ZEA određene CD-ELISA-testom statistički značajno koreliraju s rezultatima dobivenim s TLC. OTA je potvrđen metodom TLC samo u jednom uzorku zbog visokog limita detekcije. Dokazane koncentracije su ispod razina dopuštenih za krmiva, dok je 29 % uzoraka žitarica sadržavalo FBs, OTA ili ZEA u koncentracijama iznad dopuštenih u hrani za ljude. Kokontaminacija s dvama odnosno trima toksinima varirala je između 4.2 % i 54 % odnosno između 4.2 % i 7.6 %. Dugotrajni unos AFs, OTA, FBs i ZEA putem hrane može povećati rizik od razvoja različitih kroničnih bolesti zbog njihova mogućega sinergističkog djelovanja
Quantitative trait locus analysis identifies Gabra3 as a regulator of behavioral despair in mice
The Tail Suspension Test (TST), which measures behavioral despair, is widely used as an animal model of human depressive disorders and antidepressant efficacy. In order to identify novel genes involved in the regulation of TST performance, we crossed an inbred strain exhibiting low immobility in the TST (RIIIS/J) with two high-immobility strains (C57BL/6J and NZB/BlNJ) to create two distinct F2 hybrid populations. All F2 offspring (n = 655) were genotyped at high density with a panel of SNP markers. Whole-genome interval mapping of the F2 populations identified statistically significant quantitative trait loci (QTLs) on mouse chromosomes (MMU) 4, 6, and X. Microarray analysis of hippocampal gene expression in the three parental strains was used to identify potential candidate genes within the MMUX QTLs identified in the NZB/BlNJ × RIIIS/J cross. Expression of Gabra3, which encodes the GABAA receptor α3 subunit, was robust in the hippocampus of B6 and RIIIS mice but absent from NZB hippocampal tissue. To verify the role of Gabra3 in regulating TST behavior in vivo, mice were treated with SB-205384, a positive modulator of the α3 subunit. SB-205384 significantly reduced TST immobility in B6 mice without affecting general activity, but it had no effect on behavior in NZB mice. This work suggests that GABRA3 regulates a behavioral endophenotype of depression and establishes this gene as a viable new target for the study and treatment of human depression
Erratum to: Changes in patterns of uveitis at a tertiary referral center in Northern Italy: analysis of 990 consecutive cases
Erratum to: Changes in patterns of uveitis at a tertiary referral center in Northern Italy: analysis of 990 consecutive case
Lack of significant association of an insertion/deletion polymorphism in the angiotensin converting enzyme (ACE) gene with tropical calcific pancreatitis
BACKGROUND: The genetic basis of tropical calcific pancreatitis (TCP) is different and is explained by mutations in the pancreatic secretory trypsin inhibitor (SPINK1) gene. However, mutated SPINK1 does not account for the disease in all the patients, neither does it explain the phenotypic heterogeneity between TCP and fibro-calculous pancreatic diabetes (FCPD). Recent studies suggest a crucial role for pancreatic renin-angiotensin system during chronic hypoxia in acute pancreatitis and for angiotensin converting enzyme (ACE) inhibitors in reducing pancreatic fibrosis in experimental models. We investigated the association of ACE gene insertion/deletion (I/D) polymorphism in TCP patients using a case-control approach. Since SPINK1 mutations are proposed a modifier role, we also investigated its interaction with the ACE gene variant. METHODS: We analyzed the I/D polymorphism in the ACE gene (g.11417_11704del287) in 171 subjects comprising 91 TCP and 80 FCPD patients and compared the allelic and genotypic frequency in them with 99 healthy ethnically matched control subjects. RESULTS: We found 46% and 21% of TCP patients, 56% and 19.6% of FCPD patients and 54.5% and 19.2% of the healthy controls carrying the I/D and D/D genotypes respectively (P>0.05). No significant difference in the clinical picture was observed between patients with and without the del allele at the ACE in/del polymorphism in both categories. No association was observed with the presence or absence of N34S SPINK1 mutation in these patients. CONCLUSION: We conclude that the ACE insertion/deletion variant does not show any significant association with the pathogenesis, fibrosis and progression of tropical calcific pancreatitis and the fibro-calculous pancreatic diabetes
Does the Integration of Haptic and Visual Cues Reduce the Effect of a Biased Visual Reference Frame on the Subjective Head Orientation?
The selection of appropriate frames of reference (FOR) is a key factor in the elaboration of spatial perception and the production of robust interaction with our environment. The extent to which we perceive the head axis orientation (subjective head orientation, SHO) with both accuracy and precision likely contributes to the efficiency of these spatial interactions. A first goal of this study was to investigate the relative contribution of both the visual and egocentric FOR (centre-of-mass) in the SHO processing. A second goal was to investigate humans' ability to process SHO in various sensory response modalities (visual, haptic and visuo-haptic), and the way they modify the reliance to either the visual or egocentric FORs. A third goal was to question whether subjects combined visual and haptic cues optimally to increase SHO certainty and to decrease the FORs disruption effect.Thirteen subjects were asked to indicate their SHO while the visual and/or egocentric FORs were deviated. Four results emerged from our study. First, visual rod settings to SHO were altered by the tilted visual frame but not by the egocentric FOR alteration, whereas no haptic settings alteration was observed whether due to the egocentric FOR alteration or the tilted visual frame. These results are modulated by individual analysis. Second, visual and egocentric FOR dependency appear to be negatively correlated. Third, the response modality enrichment appears to improve SHO. Fourth, several combination rules of the visuo-haptic cues such as the Maximum Likelihood Estimation (MLE), Winner-Take-All (WTA) or Unweighted Mean (UWM) rule seem to account for SHO improvements. However, the UWM rule seems to best account for the improvement of visuo-haptic estimates, especially in situations with high FOR incongruence. Finally, the data also indicated that FOR reliance resulted from the application of UWM rule. This was observed more particularly, in the visual dependent subject. Conclusions: Taken together, these findings emphasize the importance of identifying individual spatial FOR preferences to assess the efficiency of our interaction with the environment whilst performing spatial tasks
Status and Prospects of ZnO-Based Resistive Switching Memory Devices
In the advancement of the semiconductor device technology, ZnO could be a prospective alternative than the other metal oxides for its versatility and huge applications in different aspects. In this review, a thorough overview on ZnO for the application of resistive switching memory (RRAM) devices has been conducted. Various efforts that have been made to investigate and modulate the switching characteristics of ZnO-based switching memory devices are discussed. The use of ZnO layer in different structure, the different types of filament formation, and the different types of switching including complementary switching are reported. By considering the huge interest of transparent devices, this review gives the concrete overview of the present status and prospects of transparent RRAM devices based on ZnO. ZnO-based RRAM can be used for flexible memory devices, which is also covered here. Another challenge in ZnO-based RRAM is that the realization of ultra-thin and low power devices. Nevertheless, ZnO not only offers decent memory properties but also has a unique potential to be used as multifunctional nonvolatile memory devices. The impact of electrode materials, metal doping, stack structures, transparency, and flexibility on resistive switching properties and switching parameters of ZnO-based resistive switching memory devices are briefly compared. This review also covers the different nanostructured-based emerging resistive switching memory devices for low power scalable devices. It may give a valuable insight on developing ZnO-based RRAM and also should encourage researchers to overcome the challenges
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