Photoacoustic characterization of TiO2 thin-films deposited on Silicon substrate using neural networks

In this paper, the possibility of determining the thermal, elastic and geometric characteristics of a thin TiO2 film deposited on a silicon substrate, thickness 30 mikrons, in the frequency range of 20 to 20 kHz with neural networks was analyzed. For this purpose, the substrate parameters remained the known and constant in the two-layer model and nano layer thin-film parameters were changed: thickness, expansion and thermal diffusivity. Prediction of these three parameters was analyzed separately with three neural networks and all of these together by fourth neural network. It was shown that neural network, which analyzed all three parameters at the same time, achieved the highest accuracy, so the use of networks that provide predictions for only one parameter is less reliable.Comment: 21 pages, 5 figure

The RESET project: constructing a European tephra lattice for refined synchronisation of environmental and archaeological events during the last c. 100 ka

This paper introduces the aims and scope of the RESET project (. RESponse of humans to abrupt Environmental Transitions), a programme of research funded by the Natural Environment Research Council (UK) between 2008 and 2013; it also provides the context and rationale for papers included in a special volume of Quaternary Science Reviews that report some of the project's findings. RESET examined the chronological and correlation methods employed to establish causal links between the timing of abrupt environmental transitions (AETs) on the one hand, and of human dispersal and development on the other, with a focus on the Middle and Upper Palaeolithic periods. The period of interest is the Last Glacial cycle and the early Holocene (c. 100-8 ka), during which time a number of pronounced AETs occurred. A long-running topic of debate is the degree to which human history in Europe and the Mediterranean region during the Palaeolithic was shaped by these AETs, but this has proved difficult to assess because of poor dating control. In an attempt to move the science forward, RESET examined the potential that tephra isochrons, and in particular non-visible ash layers (cryptotephras), might offer for synchronising palaeo-records with a greater degree of finesse. New tephrostratigraphical data generated by the project augment previously-established tephra frameworks for the region, and underpin a more evolved tephra 'lattice' that links palaeo-records between Greenland, the European mainland, sub-marine sequences in the Mediterranean and North Africa. The paper also outlines the significance of other contributions to this special volume: collectively, these illustrate how the lattice was constructed, how it links with cognate tephra research in Europe and elsewhere, and how the evidence of tephra isochrons is beginning to challenge long-held views about the impacts of environmental change on humans during the Palaeolithic. © 2015 Elsevier Ltd.RESET was funded through Consortium Grants awarded by the Natural Environment Research Council, UK, to a collaborating team drawn from four institutions: Royal Holloway University of London (grant reference NE/E015905/1), the Natural History Museum, London (NE/E015913/1), Oxford University (NE/E015670/1) and the University of Southampton, including the National Oceanography Centre (NE/01531X/1). The authors also wish to record their deep gratitude to four members of the scientific community who formed a consultative advisory panel during the lifetime of the RESET project: Professor Barbara Wohlfarth (Stockholm University), Professor Jørgen Peder Steffensen (Niels Bohr Institute, Copenhagen), Dr. Martin Street (Romisch-Germanisches Zentralmuseum, Neuwied) and Professor Clive Oppenheimer (Cambridge University). They provided excellent advice at key stages of the work, which we greatly valued. We also thank Jenny Kynaston (Geography Department, Royal Holloway) for construction of several of the figures in this paper, and Debbie Barrett (Elsevier) and Colin Murray Wallace (Editor-in-Chief, QSR) for their considerable assistance in the production of this special volume.Peer Reviewe

Characterization of two poplar homologs of the GRAS/SCL gene, which encodes a transcription factor putatively associated with salt tolerance

To cope with soil salinity, which is one of the most severe forms of abiotic stress, efforts are being undertaken to enhance the salt tolerance of economically important poplar clones in the Vojvodina region of Serbia. One approach is to screen nucleotide diversity in candidate genes (CG) in several poplar clones of high economic importance to Serbia to search for associations with salt stress tolerance. As plant-specific GRAS/SCL transcription factors (TFs) play diverse roles in abiotic stress resistance, two poplar homologs of GRAS/SCL TFs were chosen to differentiate the species background with respect to salt tolerance. A BLAST search of the Populus trichocarpa genome using the P. euphratica gene GRAS/SCL TF_GH611858 sequence identified two putative orthologs, Scaf_5 and Scaf_7, with identities of 100% and 94%, respectively. Primers were designed in identical sequences of Scaf_5 and Scaf_7 to amplify fragments of GRAS/SCL TF orthologs in four poplar clones that are economically important to Serbia. The primers spanned regions where, at least in P. trichocarpa, single nucleotide polymorphisms (SNPs) are present, thereby increasing the probability of distinguishing Scaf_5 and Scaf_7 orthologs in the four clones. Alignments and analyses of the gene fragments revealed that both orthologs were representative of the genetic diversity between different poplar clones, and the identified SNP markers differentiated the four poplar clones with respect to salt tolerance

Conduction of Heat in Inhomgeneous Solids

In this letter we present a method for calculation of linear heat flow in inhomogeneous solids. The method is based on the evaluation of transfer matrices for each layer in a multilayered structure from the Laplace transformation of the partial differential equation of heat conduction. The multilayered structure is then described by a matrix obtained as a chain of products of individual layer transfer matrices and corresponding boundary thermal resistivity matrices. The analytic expression for the nth power of the multilayered transfer matrix is found, describing a periodic multilayered structure composed of n equal multilayered structures. The application of the presented method for calculation of photothermal signals is also shown. Dispersion relation for the thermal waves in inhomogeneous solids is obtained from the matrix elements of the transfer matrix. Finally, from the dispersion relation explicit expressions for the effective values of thermal diffusivity and conductivity of both the discontinuously and continuously inhomogeneous solids are evaluated

Polymorphism of ITS1 and ITS2 regions within and between three distant population of Schizophyllum commune

Schizophyllum commune is one of the most widely distributed fungi and can be isolated from all continents, except for Antarctica. It has an important role as wood decomposer since it is mostly found on fallen branches and timber of deciduous trees, but it can also colonize softwood as well as grass silage. As an edible and medicinal mushroom, it has been shown to have various biological functions including anti-tumor, antioxidative and anti-inflammatory activity. Investigation of molecular diversity of this cosmopolitan species is important since it can make us understand what genetic traits are important in maintaining the global success of this species. In this study we analyzed polymorphisms of ITS1 and ITS2 sequences of S. commune populations from Italy, India and China. Italian sequences were obtained from herbaria samples of S. commune sporocarps from University of Palermo while Indian and Chinese sequences were downloaded from UNITE database. ITS1 and ITS2 regions of all analyzed sequences were extracted using ITSx software and variability of these regions was observed separately. Phylogenetic trees were constructed with MEGA 6 software using Neighbour joining method with 1000 Bootstrap replicates. Trees were constructed using ITS1 and ITS2 sequences separately, as well as concatenated ITS1 and ITS2 regions. ITS1 sequences were more variable (21,16%) than sequences of ITS2 region (11,15%). Variability of ITS1 region within Indian, Chinese and Italian population was 15,32; 5,1 and 1,45% respectively, while variation for same populations of ITS2 region was 4,29; 3,43 and 4,72% respectively. All three phylogenetic trees had similar topologies and the best supported tree was one constructed with concatenated ITS1 and ITS2 sequences. Trees based on ITS1 and ITS2 sequences had 4 major clades within S. commune clade, while ITS1/ITS2 tree showed grouping of 6 major clades and several subclades. Majority of sequences from India were grouped in one or two distinct clades in all analyzed trees which are in correlation with their high variability within ITS1 region. Sequences from Italy and China were mostly clustered in one clade, but with low bootstrap value which indicate high similarity between them. Since there was no clear geographic clustering of the sequences from different geographic origins, our results indicate that ITS1 and ITS2 regions of the S. commune genome are not informative enough, and should be used with additional molecular markers for investigation of geographic distribution of this species. Since S. commune is one of the most widely distributed fungi it can be possible that our results indicate that populations of S. commune have global homogeneity achieved by intensive gene flow through long distance spore dispersal

Measurement of Midregional Pro-Atrial Natriuretic Peptide to Discover Atrial Fibrillation in Patients With Ischemic Stroke

Background: Midregional pro-atrial natriuretic peptide (MR-proANP) is a promising biomarker to differentiate the underlying etiology of acute ischemic stroke (AIS). Objectives: This study aimed to determine the role of MR-proANP for classification as cardioembolic (CE) stroke, identification of newly diagnosed atrial fibrillation (NDAF), and risk assessment for major adverse cardiovascular events (MACE). Methods: This study measured MR-proANP prospectively collected within 24 hours after symptom-onset in patients with AIS from the multicenter BIOSIGNAL (Biomarker Signature of Stroke Aetiology) cohort study. Primary outcomes were CE stroke etiology and NDAF after prolonged cardiac monitoring, as well as a composite outcome of MACE (recurrent cerebrovascular events, myocardial infarction, or cardiovascular death) within 1 year. Logistic/Poisson and subproportional hazard regression were applied to evaluate the association between MR-proANP levels and outcomes. Additionally, a model for prediction of NDAF was derived and validated as a decision tool for immediate clinical application. Results: Between October 1, 2014, and October 31, 2017, this study recruited 1,759 patients. Log10MR-proANP levels were associated with CE stroke (OR: 7.96; 95% CI: 4.82-13.14; risk ratio: 3.12; 95% CI: 2.23-4.37), as well as NDAF (OR: 35.3; 95% CI: 17.58-71.03; risk ratio: 11.47; 95% CI: 6.74-19.53), and MACE (subdistributional HR: 2.02; 95% CI: 1.32-3.08) during follow-up. The model to predict NDAF including only age and MR-proANP levels had a good discriminatory capacity with an area under the curve of 0.81 (95% CI: 0.76-0.86), was well calibrated (calibration in the large: −0.086; calibration slope 1.053), and yielded higher net-benefit compared with validated scores to predict NDAF (AS5F score, CHA2DS2-VASc [Congestive Heart Failure, Hypertension, Age ≥65 or ≥75, Diabetes, Prior Cardioembolic Event, (female) Sex, or Vascular Disease] score). Conclusions: MR-proANP is a valid biomarker to determine risk of NDAF and MACE in patients with AIS and can be used as a decision tool to identify patients for prolonged cardiac monitoring. (Biomarker Signature of Stroke Aetiology Study: The BIOSIGNAL study [BIOSIGNAL]; NCT02274727) © 2022 American College of Cardiology Foundatio