A new subsurface record of the Pliensbachian-Toarcian, Lower Jurassic, of Yorkshire

Here, we describe the upper Pliensbachian to middle Toarcian stratigraphy of the Dove's Nest borehole, which was drilled near Whitby, North Yorkshire, in 2013. The core represents a single, continuous vertical section through unweathered, immature Lower Jurassic sedimentary rocks. The thickness of the Lias Group formations in the Dove's Nest core is approximately the same as that exposed along the North Yorkshire coast between Hawsker Bottoms and Whitby. The studied succession consists of epeiric-neritic sediments and comprises cross-laminated very fine sandstones, (oolitic) ironstones, and argillaceous mudstones. Dark argillaceous mudstone is the dominant lithology. These sediments were deposited in the Cleveland Basin, a more subsident area of an epeiric sea, the Laurasian Sea. We present a set of geochemical data that includes organic carbon isotope ratios (δ13Corg) and total organic carbon (TOC). The δ13Corg record contains a negative excursion across the Pliensbachian–Toarcian boundary and another in the lower Toarcian that corresponds to the Toarcian Oceanic Anoxic Event (T-OAE). Below the T-OAE negative excursion, δ13Corg values are less 13C-depleted than above it. We find no evidence of a long-term δ13Corg positive excursion. TOC values below the T-OAE negative excursion are lower than above it. Sedimentary evidence suggests that, during much of the Pliensbachian–Toarcian interval, the seafloor of the Cleveland Basin was above storm wave-base and that storm-driven bottom currents were responsible for much sediment erosion, transport, and redeposition during the interval of oceanic anoxia. The abrupt shifts observed in the δ13Corg record (lower Toarcian) are likely to reflect the impact of erosion by storms on the morphology of the δ13C record of the T-OAE

Dynamic Control of Photoresponse in ZnO-Based Thin-Film Transistors in the Visible Spectrum

Cataloged from PDF version of article.We present ZnO-channel thin-film transistors with actively tunable photocurrent in the visible spectrum, although ZnO band edge is in the ultraviolet. ZnO channel is deposited by atomic layer deposition technique at a low temperature (80 C), which is known to introduce deep level traps within the forbidden band of ZnO. The gate bias dynamically modifies the occupancy probability of these trap states by controlling the depletion region in the ZnO channel. Unoccupied trap states enable the absorption of the photons with lower energies than the bandgap of ZnO. Photoresponse to visible light is controlled by the applied voltage bias at the gate terminal

Plasmonically enhanced hot electron based photovoltaic device

Cataloged from PDF version of article.Hot electron photovoltaics is emerging as a candidate for low cost and ultra thin solar cells. Plasmonic means can be utilized to significantly boost device efficiency. We separately form the tunneling metal-insulator-metal (MIM) junction for electron collection and the plasmon exciting MIM structure on top of each other, which provides high flexibility in plasmonic design and tunneling MIM design separately. We demonstrate close to one order of magnitude enhancement in the short circuit current at the resonance wavelengths. (C) 2013 Optical Society of Americ

Modeling abstinence education effectiveness

Background: Controversy about the effectiveness of abstinence education has posed troubling dilemmas for everyone involved in this area of study. Strident statements about the lack of efficacy of abstinence education have approached the level of bitter ideology. One remedy to lessen this focus on ideology is to provide a broader analysis of program efforts. Method: This paper provides an innovative analysis of a community-based abstinence education program that encompassed multiple schools across several counties that includes thousands of students. The design addressed many deficits in published studies; it used hierarchical linear modeling to remedy the design flaws of a simple pretest-posttest analysis. Results: Pretests were the principal predictors of posttest scores. Gender was also a significant predictor of posttest scores. Age however was not a significant predictor. An interaction between gender and age was a significant predictor although a three-way interaction of gender x age x race was not. Conclusion: Implications for the findings are stated with recommendations for further research

Effect of Hf addition on reciprocating wear performance of ZrN coatings

Bu çalışmada, ZrN ve (Zr, %12 Hf)N kaplamaların aşınma davranışları incelenmiştir. Kaplamalar Zr ve %21Hf alaşımlı Zr katotların kombinasyonu ile üretilmiştir. Üretilen kaplamaların aşınma deneyleri, karşılıklı kazımalı aşınma deney cihazında, 1.5 N sabit yük altında ve 0.02 mm/s deney hızında 10 mm çapındaki Al2O3 bilyenin numune yüzeylerine sürtünmesi ile gerçekleştirilmiştir. Deney sonrası numune yüzeyinde oluşan aşınma izleri, yüzey profilometresi yardımı ile incelenmiş ve deney sonuçları aşınma iz alanları ölçülerek mm2 cinsinden alan kaybına göre değerlendirilmiştir. Deney sonuçları, (Zr, %12 Hf)N kaplamanın ZrN kaplamaya göre daha az aşındığını ve Hf ilavesinin aşınmaya karşı direnci artırdığını  göstermiştir.Anahtar Kelimler: Kaplama, FBB, ZrN, Hf, aşınma.In this study, a commercial ZrN and new (Zr, Hf)N coatings by alloying ZrN with Hf were deposited on hardened AISI D2 quality cold work tool steel plates by arc PVD technique. The coatings were prepared using combination of two cathodes under the equvalent PVD process conditions. ZrN and (Zr, %12 Hf)N coatings were obtained by utilising two Zr cathodes and one Zr and one Zr+21% Hf cothodes, respectively. The characterisation of the coatings were made by Scanning Electron Microscopic (SEM) examinations, X-ray diffraction analyses (XRD), hardness and adhesion tests as well as roughness and thickness measurements. Hardness measurements were carried out ultramicrohardness tester with a Vickers pyramid indenter. The indentation procedure consisted of 60 steps, with a waiting period between consecutive steps of 1 s. During the tests, load (P)-indentation depth (h)-time (t) data were recorded. Hardness measurements were performed under constant load of 25 mN. In order to investigate adhesion properties of the ZrN and the (Zr, 12% Hf)N coatings, scratch tests were used. The coatings were scratched up to 100 N normal load by using 10 mm/min scratching speed and 100 N/min loading speed. The dry sliding wear behaviour of ZrN and (Zr,12%Hf)N were examined by a reciprocating wear tester in ambient atmoshper. Alloying of ZrN coating with 12% Hf did not change the hardness significantly, but achieved an improvement on adhesion strength and wear resistance.Keywords: Coating, PVD, ZrN, Hf, wear

Edoxaban vs. warfarin in patients with atrial fibrillation on amiodarone: a subgroup analysis of the ENGAGE AF-TIMI 48 trial

Background In the ENGAGE AF-TIMI 48 trial, the higher-dose edoxaban (HDE) regimen had a similar incidence of ischaemic stroke compared with warfarin, whereas a higher incidence was observed with the lower-dose regimen (LDE). Amiodarone increases edoxaban plasma levels via P-glycoprotein inhibition. The current pre-specified exploratory analysis was performed to determine the effect of amiodarone on the relative efficacy and safety profile of edoxaban. Methods and results At randomization, 2492 patients (11.8%) were receiving amiodarone. The primary efficacy endpoint of stroke or systemic embolic event was significantly lower with LDE compared with warfarin in amiodarone treated patients vs. patients not on amiodarone (hazard ratio [HR] 0.60, 95% confidence intervals [CIs] 0.36-0.99 and HR 1.20, 95% CI 1.03-1.40, respectively; P interaction <0.01). In patients randomized to HDE, no such interaction for efficacy was observed (HR 0.73, 95% CI 0.46-1.17 vs. HR 0.89, 95% CI 0.75-1.05, P interaction = 0.446). Major bleeding was similar in patients on LDE (HR 0.35, 95% CI 0.21-0.59 vs. HR 0.53, 95% CI 0.46-0.61, P interaction = 0.131) and HDE (HR 0.94, 95% CI 0.65-1.38 vs. HR 0.79, 95% CI 0.69-0.90, P interaction = 0.392) when compared with warfarin, independent of amiodarone use. Conclusions Patients randomized to the LDE treated with amiodarone at the time of randomization demonstrated a significant reduction in ischaemic events vs. warfarin when compared with those not on amiodarone, while preserving a favourable bleeding profile. In contrast, amiodarone had no effect on the relative efficacy and safety of HD

Liver metastases from colorectal cancer: regional intra-arterial treatment following failure of systemic chemotherapy

This study was designed to determine response rate, survival and toxicity associated with combination chemotherapy delivered intra-arterially to liver in patients with hepatic metastases of colorectal origin refractory to standard systemic treatment. A total of 28 patients who failed prior systemic treatment with fluoropyrimidines received a median of 5 cycles of intra-arterial treatment consisting of 5-fluorouracil 700 mg/m2/d, leucovorin 120 mg/m2/d, and cisplatin 20 mg/m2/d for 5 consecutive days. Cycles were repeated at intervals of 5–6 weeks. A major response was achieved in 48% of patients: complete response in 8% and partial response in 40%. The median duration of response was 11.5 months. Median survival was 12 months at a median follow up of 12 months. On multivariate analysis, the only variables with a significant impact on survival were response to treatment and performance status. Toxicity was moderate: grades III–IV neutropenia occurred in 29% of patients. Most of the patients complained of fatigue lasting for a few days following each cycle. There were no cases of hepatobiliary toxicity. These findings indicate that regional intra-arterial treatment should be considered in selected patients with predominantly liver disease following failure of standard treatment. © 2001 Cancer Research Campaign http://www.bjcancer.co

Plasmonically enhanced ZnO thin-film-photo-transistor with dynamic responsivity control

We fabricated an ZnO based thin-film photo-transistor with electrically tunable photo-responsivity operating in the UV and visible spectra and designed plasmonic structures enhancing the device performance up to 6 folds below the band-gap of ZnO. © 2013 IEEE