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In pipeline ultrasonic testing, the accurate identification of defect types is a prerequisite for quantifying defect sizes. To this end, this paper proposes a defect identification algorithm based on the combination of Wavelet Packet Transform (WPT), Distance Evaluation Technique (DET) and GA-SVM to precisely identify defect boundaries. First, the ultrasonic echo signals are processed using WPT to more accurately extract defect information. Then, DET is employed to eliminate redundant feature parameters, which are sorted by sensitivity to determine the input feature parameters for the GA-SVM. On this basis, a self-developed ultrasonic testing experimental system is used to collect ultrasonic echo signals from Q235 steel pipes with cylindrical, spherical, and conical defects at different spatial orientations of the probe and the pipe. After processing and identifying the signals, it was found that the proposed algorithm achieves an average identification accuracy of 99% for different types of defects, thereby realising automatic identification of pipeline defects. The results provide new ideas and methods for the intelligent identification of volumetric defect types in pipeline ultrasonic internal testing and promote the development of industrial-grade ultrasonic internal detectors. [ABSTRACT FROM AUTHOR]

Introduction: The aim of this study was to assess whether the choice between double embryo transfer (DET) and single embryo transfer (SET) in healthy women of advanced maternal age (AMA) was associated with an increased risk of adverse outcomes. Materials and Methods: Healthy women aged 39?40 years who achieved live birth after in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) treatment between 2009 and 2020 at Karolinska University Hospital, Stockholm in Sweden, were included in this prospective, single-center cohort study. Results: A total of 310 women, who underwent IVF/ICSI treatments and achieved live births, were included in our analysis. Within this cohort, 78% of the women received SET, while 22% received DET. Nulliparity was common in both the SET (62.7%) and DET (85.3%) groups. Fresh embryo transfers were more prevalent in the DET group (91.2%) than in the SET group (31.1%). The rate of pregnancy-induced hypertension was higher in the SET group (8.3%) compared to the DET group (1.5%, p?=?0.048). Furthermore, the DET group had a significantly higher rate of twin pregnancies (13.2%) compared to the SET group (0.4%). No statistically significant differences were observed in composite obstetric and perinatal complications between the SET and DET groups across all model estimates following different adjustments. Clinical Trial Registration number: ClinicalTrials.gov NTC04602962. Conclusions: While DET was more common in nulliparous women and associated with a higher rate of twin pregnancies, our analysis did not reveal significant differences in adverse outcomes between the SET and DET groups after comprehensive adjustments. Our study suggests that in the absence of co-morbidities, meticulous patient selection coupled with comprehensive maternal care can potentially mitigate potential DET-associated risks in women of AMA.

Amide herbicides have been extensively used worldwide and have received substantial attention due to their adverse environmental effects. Here, a novel amidohydrolase gene was identified from a soil metagenomic library using diethyl terephthalate (DET) as a screening substrate. The recombinant enzyme, AmiH52, was heterologously expressed in Escherichia coli and later purified and characterized, with the highest activity occurring at 40 ℃ and pH 8.0. AmiH52 was demonstrated to have both esterase and amidohydrolase activities, which exhibited highly specific activity for p-nitrophenyl butyrate (2669 U/mg) and degrading activity against several amide herbicides. In particular, it displayed the strongest activity against propanil, with a high degradation rate of 84% at 8 h. A GC–MS analysis revealed that propanil was transformed into 3,4-dichloroaniline (3,4-DCA) during this degradation. The molecular interactions and binding stability were then analyzed by molecular docking and molecular dynamics simulation, which revealed that several key amino acid residues, including Tyr164, Trp66, Ala59, Val283, Arg58, His33, His191, and His226, are involved in the specific interactions with propanil. This study provides a function-driven screening method for amide herbicide hydrolase from the metagenomic libraries and a promising propanil-degrading enzyme (AmiH52) for potential applications in environmental remediation. [ABSTRACT FROM AUTHOR]

Electrical bus is needed for the operation of all active spacecraft systems and subsystems. In the spacecraft mechanism, the battery charging system and the bus storage continued with bus control, the conditioning and bus distribution is an essential part for keeping the spacecraft in working mode. In this paper, the discussion for electrical power system (EPS) analysis in the spacecraft body will be elaborated from the previous research papers on this subject covering the topics of solar array, solar array drive, over current and over voltage protection, battery charging and discharging, bus control, conversion.

Antimony (Sb) pollution has raised increasing public concerns and its rapid on-site screening is central for the risk assessment. Herein, we proposed two gel-based methods based on colorimetric diffusive equilibrium in thin films (DET) and surface-enhanced Raman scattering (SERS), for two-dimensional imaging and sensitive detection of Sb(III) by revisiting the phenylfluorone (PhF) complexation reaction. PhF was well dispersed in the polyvinyl alcohol (PVA) hydrogel and reacted with Sb(III) in the DET gel to form a strong PhF-Sb(III) complex. The distribution of Sb(III) was easily visualized at a submillimeter resolution using computer imaging densitometry, with a detection limit (LOD) of ∼100 nmol L−1. Field application in the Sb mine area reveals limited dissolved Sb(III) penetrating the redox barrier below the sediment-water interface by 20 mm in rivers and tailing pond sediments. To improve the detection sensitivity and apply the principle to trace Sb quantification, a SERS platform was established by anchoring PhF on the hydrogel-stabilized Ag nanoparticles via C–O–Ag bonding to specifically detect Raman-inactive Sb(III). Benefiting from the high SERS activity of PhF and enrichment ability of hydrogel, Sb(III) was quantified with a LOD of 1.2–10.7 nmol L−1 depending on the sample volume. The coexisting ions at a 100-fold higher concentration than Sb(III) resulted in only 3.3–10.4 % variation in SERS intensity, indicating a negligible interference on the SERS platform. The platform exhibited a RSD of 6.6–13.1 % and acceptable recoveries for various environmental matrices, highlighting its promise in on-site application. [Display omitted] • Two polyvinyl alcohol gel methods for Sb(III) detection were developed. • Colorimetric DET gel provides submillimeter 2D imaging at a 100 nM detection limit. • Enrichment-type SERS gel achieves detection limits as low as 1.2 nM. • Field study shows limited Sb(III) penetration beyond the sediment-water interface. [ABSTRACT FROM AUTHOR]

Electrical bus is needed for the operation of all active spacecraft systems and subsystems. In the spacecraft mechanism, the battery charging system and the bus storage continued with bus control, the conditioning and bus distribution is an essential part for keeping the spacecraft in working mode. In this paper, the discussion for electrical power system (EPS) analysis in the spacecraft body will be elaborated from the previous research papers on this subject covering the topics of solar array, solar array drive, over current and over voltage protection, battery charging and discharging, bus control, conversion. [ABSTRACT FROM AUTHOR]

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Background Nowadays, both customers and producers prefer thin-tailed fat sheep. To effectively breed for this phenotype, it is important to identify candidate genes and uncover the genetic mechanism related to tail fat deposition in sheep. Accumulating evidence suggesting that post-transcriptional modification events of precursor-messenger RNA (pre-mRNA), including alternative splicing (AS) and alternative polyadenylation (APA), may regulate tail fat deposition in sheep. Differentially expressed transcripts (DETs) analysis is a way to identify candidate genes related to tail fat deposition. However, due to the technological limitation, post-transcriptional modification events in the tail fat of sheep and DETs between thin-tailed and fat-tailed sheep remains unclear. Methods In the present study, we applied pooled PacBio isoform sequencing (Iso-Seq) to generate transcriptomic data of tail fat tissue from six sheep (three thin-tailed sheep and three fat-tailed sheep). By comparing with reference genome, potential gene loci and novel transcripts were identified. Post-transcriptional modification events, including AS and APA, and lncRNA in sheep tail fat were uncovered using pooled Iso-Seq data. Combining Iso-Seq data with six RNA-sequencing (RNA-Seq) data, DETs between thin- and fat-tailed sheep were identified. Protein protein interaction (PPI) network, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were implemented to investigate the potential functions of DETs. Results In the present study, we revealed the transcriptomic complexity of the tail fat of sheep, result in 9,001 potential novel gene loci, 17,834 AS events, 5,791 APA events, and 3,764 lncRNAs. Combining Iso-Seq data with RNA-Seq data, we identified hundreds of DETs between thin- and fat-tailed sheep. Among them, 21 differentially expressed lncRNAs, such as ENSOART00020036299, ENSOART00020033641, ENSOART00020024562, ENSOART00020003848 and 9.53.1 may regulate tail fat deposition. Many novel transcripts were identified as DETs, including 15.527.13 (DGAT2), 13.624.23 (ACSS2), 11.689.28 (ACLY), 11.689.18 (ACLY), 11.689.14 (ACLY), 11.660.12 (ACLY), 22.289.6 (SCD), 22.289.3 (SCD) and 22.289.14 (SCD). Most of the identified DETs have been enriched in GO and KEGG pathways related to extracellular matrix (ECM). Our result revealed the transcriptome complexity and identified many candidate transcripts in tail fat, which could enhance the understanding of molecular mechanisms behind tail fat deposition. [ABSTRACT FROM AUTHOR]

To progress towards as quick as possible feasible pre-design of space missions, spacecraft early design today is organized gathering together experts from different spacecraft subsystems that share information (and results). This Concurrent Design (CD) approach needs accurate but quick solutions from all subsystems involved in each phase of that mission early design. At IDR/UPM Institute researchers have been working in simplified models for the spacecraft power distribution subsystem. In the present paper three models, for solar panels, the battery and DC-DC converters are described and tested with experimental data. The models were designed to be coupled within the simulation of a spacecraft mission. The model regarding the solar panels is focused on accurately estimate the power production from the panels, whereas the model of the batteries is based on the discharged energy rate as the main/control parameter instead of the discharged/charged ampere·hour rate. Finally, the solar-panels/battery coupled design is described in this paper, the UPMSat-2 mission being used as case study. • The testing results related DC-DC spacecraft converters are used to model these parts. • Spacecraft solar panels are modeled with simplified approaches based on information from the manufacturer. • A simple model for Li-ion battery performance is proposed. • The power system of the UPMSat-2 spacecraft mission is simulated. • DET and MPPT are compared, DET being more efficient for the UPMSat-2 mission. [ABSTRACT FROM AUTHOR]

Introduction: The aim of this study was to assess whether the choice between double embryo transfer (DET) and single embryo transfer (SET) in healthy women of advanced maternal age (AMA) was associated with an increased risk of adverse outcomes., Materials and Methods: Healthy women aged 39-40 years who achieved live birth after in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) treatment between 2009 and 2020 at Karolinska University Hospital, Stockholm in Sweden, were included in this prospective, single-center cohort study., Results: A total of 310 women, who underwent IVF/ICSI treatments and achieved live births, were included in our analysis. Within this cohort, 78% of the women received SET, while 22% received DET. Nulliparity was common in both the SET (62.7%) and DET (85.3%) groups. Fresh embryo transfers were more prevalent in the DET group (91.2%) than in the SET group (31.1%). The rate of pregnancy-induced hypertension was higher in the SET group (8.3%) compared to the DET group (1.5%, p  = 0.048). Furthermore, the DET group had a significantly higher rate of twin pregnancies (13.2%) compared to the SET group (0.4%). No statistically significant differences were observed in composite obstetric and perinatal complications between the SET and DET groups across all model estimates following different adjustments.Clinical Trial Registration number: ClinicalTrials.gov NTC04602962., Conclusions: While DET was more common in nulliparous women and associated with a higher rate of twin pregnancies, our analysis did not reveal significant differences in adverse outcomes between the SET and DET groups after comprehensive adjustments. Our study suggests that in the absence of co-morbidities, meticulous patient selection coupled with comprehensive maternal care can potentially mitigate potential DET-associated risks in women of AMA., (© Ellen-Elena Reinolds et al., 2024; Published by Mary Ann Liebert, Inc.)

Background This study aimed to evaluate the offspring sex ratio, born through fresh and cryo-thawed single blastocyst (BL) transfers regarding a single morphological, static parameter, namely, BL diameter. Methodology This retrospective, observational study was conducted at an assisted reproductive technology (ART) center, Kinderwunschzentrum Niederrhein Germany. We conducted a statistical analysis of all births resulting from fresh and thawed in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) cycles after a single embryo transfer (SET). The main outcome measure was the offspring sex ratio after SET of a day five BL in relation to the BL diameter measurement. Results There were more female than male babies born in our study. We observed a tendency for BL to have a higher diameter, resulting in female offspring, which was not statistically relevant. We also compared the BL diameter in the fresh embryo transfer (ET) group with that of the cryo-thawed ET group, showing a tendency toward a larger diameter in the fresh ET group. In the ICSI cycles, there was a higher tendency for a larger BL diameter when compared to IVF cycles. In the fresh ET cycles, BL leading to the male sex at birth had a tendency toward a larger diameter than the female BL. In the cryo-thaw ET cycles, BL leading to the female sex had a tendency toward a larger diameter than the male BL. Conclusions Our results showed a tendency in the sex of offspring toward the female sex and no significant difference in the BL diameter of BL leading to birth after ART and consecutive transfer of day five BL., Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. Ethics Committee, Aerztekammer Nordrhein issued approval 293/2022. Animal subjects: All authors have confirmed that this study did not involve animal subjects or tissue. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Hajder et al.)

The localized plasmon resonance enhancement mechanisms were investigated as a function to increase the shell thickness of the prepared hexagonal nanodiscs arrays of Au@TiO2 core‐shell. The bare Au hexagonal nanodiscs array exhibited multiple plasmon resonance modes in the ultraviolet (UV) to near‐infrared (NIR) region. Au@TiO2 nanodiscs configuration present three different enhancement mechanisms with increasing TiO2 shell thickness. First, a strengthened plasmon‐induced resonance energy transfer (PIRET) for higher plasmonic resonance mode in the UV region. Second, redshifted and broadened direct electron transfer (DET) processes for the plasmonic dipole resonance mode from the Vis to the NIR region. Third, an increased hybridization retardation effect for the higher plasmonic mode in the Vis region. By using a facile and cost‐effective technique (nonlithographic route) to fabricate highly ordered core‐shell nanodiscs arrays (Au@TiO2 hexagonal nanodiscs) on a large area of Si substrate (>cm2) via an ultrathin alumina membrane (UTAM), this technique provides a perfect shadow mask to fabricate Au nanodiscs arrays; furthermore, the shadow effect of UTAM pores offers enough space to cover Au nanodiscs by the TiO2. These plasmonic core‐shell nanodiscs reveal a highly promising pathway to discovering new enhancement phenomena that can be applied in diverse applications such as plasmon‐enhanced energy conversion, biosensing, and surface‐enhanced vibrational spectroscopy. [ABSTRACT FROM AUTHOR]

Network motifs play an important role in the structural analysis of biological networks. Identification of such network motifs leads to many important applications such as understanding the modularity and the large-scale structure of biological networks, classification of networks into super-families, and protein function annotation. However, identification of large network motifs is a challenging task as it involves the graph isomorphism problem. Although this problem has been studied extensively in the literature using different computational approaches, still there is a lot of scope for improvement. Motivated by the challenges involved in this field, an efficient and scalable network motif finding algorithm using a dynamic expansion tree is proposed. The novelty of the proposed algorithm is that it avoids computationally expensive graph isomorphism tests and overcomes the space limitation of the static expansion tree (SET) which makes it enable to find large motifs. In this algorithm, the embeddings corresponding to a child node of the expansion tree are obtained from the embeddings of a parent node, either by adding a vertex or by adding an edge. This process does not involve any graph isomorphism check. The time complexity of vertex addition and edge addition are O(n) and O(1), respectively. The growth of a dynamic expansion tree (DET) depends on the availability of patterns in the target network. Pruning of branches in the DET significantly reduces the space requirement of the SET. The proposed algorithm has been tested on a protein–protein interaction network obtained from the MINT database. The proposed algorithm is able to identify large network motifs faster than most of the existing motif finding algorithms.

Network motifs play an important role in the structural analysis of biological networks. Identification of such network motifs leads to many important applications such as understanding the modularity and the large-scale structure of biological networks, classification of networks into super-families, and protein function annotation. However, identification of large network motifs is a challenging task as it involves the graph isomorphism problem. Although this problem has been studied extensively in the literature using different computational approaches, still there is a lot of scope for improvement. Motivated by the challenges involved in this field, an efficient and scalable network motif finding algorithm using a dynamic expansion tree is proposed. The novelty of the proposed algorithm is that it avoids computationally expensive graph isomorphism tests and overcomes the space limitation of the static expansion tree (SET) which makes it enable to find large motifs. In this algorithm, the embeddings corresponding to a child node of the expansion tree are obtained from the embeddings of a parent node, either by adding a vertex or by adding an edge. This process does not involve any graph isomorphism check. The time complexity of vertex addition and edge addition are O(n) and O(1), respectively. The growth of a dynamic expansion tree (DET) depends on the availability of patterns in the target network. Pruning of branches in the DET significantly reduces the space requirement of the SET. The proposed algorithm has been tested on a protein–protein interaction network obtained from the MINT database. The proposed algorithm is able to identify large network motifs faster than most of the existing motif finding algorithms. [ABSTRACT FROM AUTHOR]

Abstract The use of grasses as cover crops in the off-season of cash crops under no-till has been largely adopted. However, soil phosphorus (P) uptake was previously shown to be reduced when ruzigrass is introduced in the rotation, affecting the viability and sustainability of this cropping system. The objective of this study was to assess the effect of ruzigrass on soil P availability and desorption kinetics under different P fertilizer application rates. A long-term field experiment where soybean (Glycine max) has been grown in rotation with ruzigrass (Urochloa ruziziensis) or fallow for 10 years, with the application of 0, 13, and 26 kg ha−1 of P, was evaluated for two consecutive years. Soil P desorption kinetics was assessed using diffusive equilibrium (DET) and gradient in thin films (DGT) techniques, as well as the DGT-induced fluxes in soils model (DIFS). Microbial biomass P (MBP) was assessed to verify if soil solution P (P DET) was reduced due to immobilization by microorganisms. Ruzigrass reduced MBP and P DET especially when P fertilizer was applied. The concentration of labile P (P DGT) was also lower after ruzigrass than in fallow. The soil ability to resupply P to soil solution was lower after ruzigrass regardless of P rates due to a slower desorption in response to the perturbation imposed by DGT. Growing ruzigrass as cover crop in the soybean off-season decreases soil P availability regardless of P fertilizer application rates by fundamentally reducing P mobility and P resupply from soil solid phase into soil solution. Highlights • The use of ruzigrass as cover crop affect soil P availability in the long-term. • Soil P desorption kinetics was assessed using diffusive gradient in thin films (DGT). • The use of DGT provided new insights into P availability, by considering the P diffusion and resupply process. • Ruzigrass decreases P availability by reducing P mobility and resupply from soil solid phase into soil solution. [ABSTRACT FROM AUTHOR]

Abstract The tanning industry uses large quantities of Cr whose contribution to the contaminant burden of aquatic organisms is not yet fully understood. The present study investigated Cr bioaccumulation by indigenous chironomids in a freshwater ecosystem impacted by tannery effluents. Total Cr content in sediments and in chironomids was determined on several occasions. Chromium distribution among sediments and pore waters, and Cr speciation in overlying and pore waters were studied in detail to understand possible factors controlling Cr bioavailability to chironomids. Total chromium concentration ranged from 69 to over 3000 μg g−1 dry weight in sediments and from negligible to over 300 μg g−1 dry weight in chironomids (values corrected for sediment gut content). Filterable (<0.45 μm) Cr concentration in overlying waters and pore waters from the surface sediment layers (upper 2 cm) ranged from 3 to 120 μg L−1, with Cr(VI) representing 0.5–28% of the total filterable Cr. Chromium profiles in pore waters as determined by diffusive equilibration in thin films (DET) and diffusive gradient in thin films (DGT) were comparable. DGT-labile Cr accounted for <2% of the total Cr measured by DET. Although Cr concentrations in sedimentary and aqueous matrices were not directly proportional to Cr levels measured in chironomids, the available findings suggested that Cr inputs from tanneries were bioavailable to resident chironomids. These observations are of particular importance considering that Cr(III), putatively of limited bioavailability and ecotoxicological concern, is the predominant redox form of Cr in bed sediments impacted by tannery discharges. The companion paper provides further insight into Cr bioavailability and effects in tannery impacted ecosystems using a combination of in situ and laboratory approaches. Graphical abstract Unlabelled Image Highlights • Leather tanning uses large quantities of Cr(III) that mostly accumulates in sediments. • Bioavailability of chromium at tannery-contaminated sites is not fully understood. • Indigenous chironomids show Cr accumulation in zones impacted by tannery discharges. • Cr accumulation in chironomids is not proportional to Cr concentration in sediments. • Chironomid Cr burden exceeds reported tolerance levels for more sensitive organisms. [ABSTRACT FROM AUTHOR]

Abstract Lipidic cubic phase systems (LCPs) are excellent carriers for immobilized enzymes due to their biocompatibility and well-defined nanoporous structure. Lipidic cubic phases act as a convenient matrix to incorporate enzymes and hold them in the vicinity of electrode surfaces in their fully active forms. Corynascus thermophilus cellobiose dehydrogenase (Ct CDH) was trapped in a monoolein cubic phase, which increased not only its stability, but also its catalytic performance with both enhanced mediated and direct electron transfer with electrodes. For studies of mediated electron transfer, three mediators with different formal potentials (E°′) were employed: horse-heart cytochrome c (cyt c), electron acceptor active with the cytochrome domain of Ct CDH, and 2,6-dichlorophenolindophenol (DCPIP) as well as hexaammineruthenium(II) chloride [Ru(NH 3)Cl 2 ] both electron acceptors with the dehydrogenase domain. Ru(NH 3)Cl 2 , having the most negative E°′ of − 0.138 V vs. Ag | AgCl at pH 7.5, gave a catalytic current for lactose oxidation of 32.10 μA cm− 2 in MOPS buffer at pH 7.5. The process carried out in the same solution but under direct electron conditions transfer resulted in a catalytic current of 9.22 μA cm− 2. Electrodes covered with Ct CDH in a LCP film retained their catalytic activity after 28 days showing a slightly increased current density after 6 days. Graphical abstract Image 2 Highlights • Lipidic cubic phase enhances enzyme catalytic activity. • Electrodes with CtCDH in cubic phase are more stable than with adsorbed enzyme. • Both DET and MET mechanism of Ct CDH can be observed in cubic phase. [ABSTRACT FROM AUTHOR]

• A DET analysis has been applied to a BWR during a hot shutdown phase. • RAVEN acts as a logic driver while MELCOR simulates the thermal–hydraulic response. • Cyberattack alters plant state variable processed by I&C disabling coolant injection systems. • DET focuses on cyberattack and recovery time that would compromise core integrity. Over the last decade, probabilistic risk assessment (PRA) for nuclear power plants shifted its focus toward simulation-based methods of evaluating safety and risk aspects. Classical reliability modeling based on static Boolean structures does not capture the dynamic nature of plants experiencing accident sequences. Dynamic PRA extends conventional reliability modeling, adding a higher degree of variability to events occuring during accident sequences. This paper demonstrates the capability of a new dynamic event tree (DET) analysis tool applicable to severe accident sequences. A cyberattack was assumed to penetrate the instrumentation system of a boiling water reactor during its hot shutdown phase, altering the thermal–hydraulic variables being processed. The analysis focused on scenarios that lead to the core being uncovered, in which the peak cladding temperature is reached due to the disabling of the cooling systems. A limiting surface is defined, associating the cyberattack timing to the recovery time limit that would compromise the core integrity. [ABSTRACT FROM AUTHOR]

In this study, polythiophene copolymers have been used as modifier for electrode surfaces in order to allow the immobilization of active pyrroloquinoline quinone dependent glucose dehydrogenase (PQQ-GDH) and to simultaneously improve the direct electrical connection of the enzyme with the electrode. Polymer films are electrosynthesized in aqueous solution without the need of surfactants onto carbon nanotubes modified gold electrodes from mixtures of 3-thiopheneacetic acid (ThCH 2 CO 2 H) and 3-methoxythiophene (ThOCH 3 ) using a potentiostatic pulse method. Polythiophene deposition significantly improves the bioelectrocatalysis of PQQ-GDH: the process starts at − 200 mV vs. Ag/AgCl and allows well-defined glucose detection at 0 V vs. Ag/AgCl with high current density. Several parameters of the electro-polymerization method have been evaluated to maximize the anodic current output after enzyme coupling. The polymer deposited by this new procedure has been morphologically and chemically characterized by different methods (SEM, EDX, FT-IR, UV–Vis, XPS and Raman spectroscopy). The bioelectrocatalytic response towards increasing glucose concentrations exhibits a dynamic range extending from 1 μM to 2 mM. The low applied potential allows to avoid interferences from easily oxidizable substances such as uric acid and ascorbic acid. Short and long-term stability has been evaluated. Finally, the PQQ-GDH electrode has been coupled to a bilirubin oxidase (BOD)- and carbon nanotube-based cathode in order to test its performance as anode of a biofuel cell. The promising results suggest a further investigation of this kind of polymers and, in particular, the study of the interaction with other enzymes in order to employ them in building up biosensors and biofuel cells. [ABSTRACT FROM AUTHOR]

The consequences of a transient in an advanced sodium-cooled fast reactor are difficult to capture with the traditional approach to probabilistic risk assessment (PRA). Numerous safety-relevant systems are passive and may have operational states that cannot be represented by binary success or failure. In addition, the specific order and timing of events may be crucial which necessitates the use of dynamic PRA tools such as ADAPT. The modifications to the SAS4A/SASSYS-1 sodium-cooled fast reactor safety analysis code for linking it to ADAPT to perform a dynamic PRA are described. A test case is used to demonstrate the linking process and to illustrate the type of insights that may be gained with this process. Newly-developed dynamic importance measures are used to assess the significance of reactor parameters/constituents on calculated consequences of initiating events. [ABSTRACT FROM AUTHOR]

Arsenic concentration in the pore water of paddy fields (C soln ) irrigated with arsenic-rich groundwater is a key parameter in arsenic uptake by rice. Pore water extracts from cores and in situ deployment of DET and DGT probes were used to measure the arsenic concentration in the pore water. Ferrihydrite (Fe) and titanium dioxide (Ti) were used as DGT binding agents. Six sampling events during different growing stages of the rice, inducing different biogeochemical conditions, were performed in one rice field. A time series of DGT experiments allow the determination of an in situ arsenic diffusion coefficient in the diffusive gel (3.34 × 10 − 6 cm 2 s − 1 ) needed to calculate the so-called C DGT (Fe) and C DGT (Ti) concentrations. Over 3 days of a given sampling event and for cores sampled at intervals smaller than 50 cm, great variability in arsenic C soln concentrations between vertical profiles was observed, with maxima of concentrations varying from 690 to 2800 μg L − 1 . Comparisons between arsenic measured C sol and C DET and calculated C DGT (Fe) and C DGT (Ti) concentrations show either, in a few cases, roughly similar vertical profiles, or in other cases, significantly different profiles. An established iron oxyhydroxide precipitation in the DET gel may explain why measured arsenic C DET concentrations occasionally exceeded C soln . The large spread in results suggests limitations to the use of DET and type of DGT probes used here for similarly representing the spatio-temporal variations of arsenic content in soil pore water in specific environmental such as paddy soils. [ABSTRACT FROM AUTHOR]

General relativity is critically reviewed on its theoretical framework, predictions, experimental tests, applications, and its impact to particle physics and cosmology. It has been shown that all three crucial experimental tests of general relativity are either invalid or not convincing. It has also been shown that general relativity has some insoluble inconsistencies, such as the singularity problem which leads to concepts like black hole, white hole, worm hole, multiverse, reversal of causality, and the multitude inconsistencies with the Big Bang cosmology. The rotational relativity is also discussed. It has been shown that no global rotational transformation exists and the rotational relativity is in conflict with the constancy and limit of speed of light. The well accepted concept of space warping by gravity is reviewed in depth. It is found that the two analytical solutions, the Schwarzschild metric and the Kerr metric, both have zero Riemann curvature scalar. It means that the space time is flat, which is borne out by the fact that the mass density parameter that measures the curvature of cosmos cannot deviate from the flat space by more than 10-58. An alternative theory to interpret the cosmic redshift--the dispersive extinction theory (DET)--is also presented. DET allows a classical stable universe infinite in space and time. [ABSTRACT FROM AUTHOR]

Bearing‐fault‐diagnosis problem can be conceived as a pattern recognition problem, which includes three main phases: feature extraction, feature selection and feature classification. Thus, to improve the performance of the whole bearing‐fault‐diagnosis system, the performance of each phase must be improved. The aim of this study is threefold. First, in the feature extraction step, a new feature extraction technique based on non‐local‐means de‐noising and empirical mode decomposition is developed to more accurately obtain fault‐characteristic information. Second, in the feature selection phase, a novel two‐stage feature selection, hybrid distance evaluation technique (DET)–particle swarm optimisation (PSO), is proposed by combining DET and PSO to select the superior combining feature subset that discriminates well among classes. Third, in the classification phase, a comparison among three types of popular classifiers: K‐nearest neighbours, probabilistic neural network and support‐vector machine is done to figure out the sensitivity of each classifier corresponding to the irrelevant and redundant features and the curse of dimensionality; then, find out a most suitable classifier incorporating with feature selection phase. The experimental results for the vibration signal of the bearing are shown to verify the effectiveness of the proposed fault‐diagnosis scheme. [ABSTRACT FROM AUTHOR]

Novel label-free impedimetric platform based on a three-dimensional interdigitated electrode array (3D-IDEA) sensor and new conductive polymer as a transducer for oxidoreductases is introduced. This platform is cost-effective, simple to construct and miniaturize. Monomer of conductive polymer N-(N’,N’-diethyldithiocarbamoylethylamidoethyl) aniline (AnD) was deposited onto 3D-IDEA by chemical polymerisation. It was found that the polymer film resistance depends on the redox-potential of the solution. For the first time polyAnD was used as enzyme immobilisation matrix. Pyrroloquinolinequinone (PQQ) dependent alcohol and glucose dehydrogenases were immobilized on 3D-IDEA covered with polyAnD by two different methods. 3D-IDEA sensors with enzymes, which were immobilised by physisorption on polyAnD layer, showed specific response in the presence of 1 μM of the corresponding substrates. Obtained results revealed that PQQ dependent dehydrogenases can re-oxidize on polyAnD via direct electron transfer (DET) from enzyme active site to the polymer surface. This process can be monitored by methods of electrochemical impedance spectroscopy (EIS) and chronoamperometry. Presented study shows that EIS method gives a useful tool for research of re-oxidation process and interaction of electroactive enzymes with conducting materials giving information required to construct and develop analytical devices. [ABSTRACT FROM AUTHOR]

The hyporheic zone of riverbed sediments has the potential to attenuate nitrate from upwelling, polluted groundwater. However, the coarse-scale (5-10 cm) measurement of nitrogen biogeochemistry in the hyporheic zone can often mask fine-scale (<1 cm) biogeochemical patterns, especially in near-surface sediments, leading to incomplete or inaccurate representation of the capacity of the hyporheic zone to transform upwelling NO3−. In this study, we utilised diffusive equilibrium in thin-films samplers to capture high resolution (cm-scale) vertical concentration profiles of NO3−, SO42−, Fe and Mn in the upper 15 cm of armoured and permeable riverbed sediments. The goal was to test whether nitrate attenuation was occurring in a sub-reach characterised by strong vertical (upwelling) water fluxes. The vertical concentration profiles obtained from diffusive equilibrium in thin-films samplers indicate considerable cm-scale variability in NO3− (4.4 ± 2.9 mg N/L), SO42− (9.9 ± 3.1 mg/l) and dissolved Fe (1.6 ± 2.1 mg/l) and Mn (0.2 ± 0.2 mg/l). However, the overall trend suggests the absence of substantial net chemical transformations and surface-subsurface water mixing in the shallow sediments of our sub-reach under baseflow conditions. The significance of this is that upwelling NO3−-rich groundwater does not appear to be attenuated in the riverbed sediments at <15 cm depth as might occur where hyporheic exchange flows deliver organic matter to the sediments for metabolic processes. It would appear that the chemical patterns observed in the shallow sediments of our sub-reach are not controlled exclusively by redox processes and/or hyporheic exchange flows. Deeper-seated groundwater fluxes and hydro-stratigraphy may be additional important drivers of chemical patterns in the shallow sediments of our study sub-reach. © 2015 The Authors. Hydrological Processes Published by John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]

Measurements of porewater alkalinity are fundamental to the study of organic matter mineralization in sediments, which plays an essential role in the global cycles of carbon and nutrients. A new colorimetric diffusive equilibration in thin film (DET) technique is described for measuring two-dimensional total alkalinity distributions in sediment porewaters at high resolution (1–2 mm 2 ). Thin polyacrylamide hydrogel layers (0.8 mm) equilibrate with the porewater and, after removal, are immediately laid onto another hydrogel containing formic acid, which reacts with alkalinity-generating species, and the pH-indicator bromophenol blue. The resultant color change is quantified using computer-imaging densitometry. The lower limit of detection is 0.2 meq L −1 and the upper measurement limit is 8 meq L −1 . Deployment in seagrass colonized sediment revealed high levels of spatial heterogeneity in the porewater alkalinity distribution, with concentrations ranging from 2.28 meq L −1 in the overlying water to 5.13 meq L −1 in some parts of the sediment. This is the first time that two-dimensional, high-resolution distributions of porewater alkalinity have been measured. [ABSTRACT FROM AUTHOR]

Abstract: We introduce diffracted electron tracking (DET), which combines two electron microscopy techniques, electron backscatter diffraction and the use of an environmental cell in a scanning electron microscope to measure changes in nanocrystal-orientation. The accuracy of DET was verified by measuring the motion of a flat gold crystal caused by the rotation or tilting of the specimen stage. DET was applied to measure the motion of semi-fixed gold nanocrystals in various environments. In addition to large motions induced in water environment, DET could detect small differences in the three-dimensional (3D) motion amplitude between vacuum environment and an Ar gas environment. DET promises to be a useful method for measuring the motion of single nanocrystals in various environments. This measuring technique may be used in a wide range of scientific fields; for example, DET may be a prospective method to track the single molecule dynamics of molecules labeled with gold nanocrystals. [Copyright &y& Elsevier]

Abstract: Constrained DET (Diffusive Equilibration in Thin films) probes equipped with 75 sampling layers of agarose gel (DGT Research©) were used to sample bottom and pore waters in marine sediment with a 2 mm vertical resolution. After retrieval, each piece of hydrogel, corresponding to 25 μL, was introduced into 1 mL of colorimetric reagent (CR) solution consisting of formic acid and bromophenol blue. After the elution/reaction time, absorbance of the latter mixture was read at 590 nm and compared to a calibration curve obtained with the same protocol applied to mini DET probes soaked in sodium hydrogen carbonate standard solutions. This method allows rapid alkalinity determinations for the small volumes of anoxic pore water entrapped into the gel. The method was assessed on organic-rich coastal marine sediments from Thau lagoon (France). Alkalinity values in the overlying waters were in agreement with data obtained by classical sampling techniques. Pore water data showed a progressive increase of alkalinity in the sediment from 2 to 10 mmol kg−1, corresponding to anaerobic respiration in organic-rich sediments. Moreover, replicates of high-resolution DET profiles showed important lateral heterogeneity at a decimeter scale. This underlines the importance of high-resolution spatial methods for alkalinity profiling in coastal marine systems. [Copyright &y& Elsevier]

The techniques of diffusive equilibrium in thin films (DET) and diffusive gradients in thin films (DGT) were used in the outer section of Songkhla Lake, Thailand in order to obtain high-resolution profiles of total dissolved and labile trace metals in the sediment pore water and investigate benthic fluxes. Six DET probes and six DGT probes were deployed at the mouths of the Phawong, Samrong and U-Taphao canals. A close correspondence could be observed between the high-resolution profiles of Fe and As, revealing a close link between the reductive remobilization of Fe oxides and the reduction of As(V). Co and Ni DGT profiles showed a close correspondence with Mn, but a narrow mobilization zone. Reductive mobilization of Mn oxides and associated metals and sulfide precipitation control the behaviour of these metals. The DGT profiles of Cu, Zn, Cd and Pb show surface maximum, probably linked to organic matter degradation. Important benthic fluxes, especially for As, were found at the mouths of the U-Taphao and Phawong canals. [ABSTRACT FROM AUTHOR]

Abstract: Here we evaluate a new field methodology for the deployment of Diffusive Equilibrium in Thin Films (DET, protected in stainless steel holders) in coarse riverbed sediments based on that originally developed for fine-grained sediments and soils. Concentration gradients of NO3 −, NH4 + and dissolved Mn were measured at cm resolution. We observed fine scale changes in NO3 −, NH4 +, and Mn concentrations in the river bed (0–30cm) that were only evident at high resolution and compared them to profiles of NO3 − and NH4 + obtained with low resolution multilevel piezometers. The range in concentrations of NO3 − and NH4 + measured through DET was larger than those measured at coarse resolution through pore water sampling from multilevel piezometer in the riverbed over the 30cm depth. According to the results, high resolution profiles of redox sensitive chemical species in riverbeds could help in identifying and resolving hotspots of biogeochemical activity. Measurements of NH4 + using DET were higher than measurements in pore water collected from the multilevel samplers. Further studies are needed to establish whether there is a systematic bias associated with either procedure for the measurement of NH4 +. [Copyright &y& Elsevier]

Abstract: The recently developed colorimetric diffusive equilibration in thin films (DET) technique for the in situ, high-resolution measurement of iron(II) in marine sediments is optimized to allow measurement of the higher iron concentrations typical of freshwater sediment porewaters. Computer imaging densitometry (CID) is used to analyze the retrieved samplers following exposure to ferrozine, a colorimetric reagent selective for iron(II). The effect of ferrozine concentration, image processing parameters and ionic strength are investigated to improve the applicability of this technique to a wider range of aquatic systems than reported in the first publications of this approach. The technique was optimized to allow detection of up to 2000μmolL−1 iron(II), a four-fold increase on the previous upper detection limit of 500μmolL−1. The CID processing of the scanned color image was also optimized to adjust the sensitivity of the assay as required; by processing the image with different color channel filters, the sensitivity of the assay can be optimized for lower concentrations (up to 100μmolL−1) or higher concentrations (up to 2000μmolL−1) of iron(II), depending on the specific site characteristics. This process does not require separate sampling probes or even separate scans of the DET gels as the color filter and grayscale conversion is done post-image capture. The optimized technique is very simple to use and provides highly representative, high-resolution (1mm) two-dimensional distributions of iron(II) in sediment porewaters. The detection limit of the optimized technique was 4.1±0.3μmolL−1 iron(II) and relative standard deviations were less than 6%. [Copyright &y& Elsevier]

BACKGROUND Instrument development is an iterative process that requires continuous efforts to ensure the psychometric soundness of the assessment tools. Previous research has provided validity evidence for the design, engineering, and technology (DET) survey in assessing K-12 teachers' familiarity with and perceptions of engineering. PURPOSE The purpose of this study was to re-examine the psychometric soundness of the DET survey with a new data set collected from elementary teachers representing a national population. In addition, details regarding how to appropriately conduct confirmatory (CFA) and exploratory (EFA) factor analyses and item analysis were presented. DESIGN/METHOD The DET survey was administered to 405 elementary teachers (second through sixth grades) between 2006 and 2010. First, a CFA was conducted to test the factor structure based on a theoretical model. Second, an EFA was used to explore and refine the factor structure. Finally, item analysis was used to evaluate individual item performance and estimate internal reliability. RESULTS While the CFA conducted using the new sample reported unsatisfactory fit indices to the previous DET model, the EFA proposed a refined four-factor solution explaining 74% of the total variance. The item analysis revealed problems with several items that possibly contributed to the CFA results. CONCLUSIONS The DET is a useful instrument with sufficient reliability and moderate validity evidence. However, we recommend revisions of its scale and several items. We also recommend future research with middle and high school teachers as well as with teachers in different cultural contexts and countries. [ABSTRACT FROM AUTHOR]

Abstract: Wetlands are capable of reducing nutrient loadings to receiving water bodies, and hence many artificial wetlands have been constructed for wastewater nutrient removal. In this study, diffusive equilibrium in thin films (DETs) and equilibrium phosphorus concentration (EPC0) analysis were used to examine the role of sediment as a nutrient source or sink in a constructed treatment wetland in summer. The effect of dredging on sediment-water nutrient exchange was also studied. Soluble reactive phosphorus (SRP), ammonium (NH4 +) and sulphate (SO4 2−) concentration profiles were measured by DET across the sediment-water interface (SWI) in both a settling pond and iris reed bed within the wetland. The SRP concentrations in the sediment pore-waters of the settling pond were extremely high (up to 29,500μg l−1) near the SWI. This is over an order of magnitude higher than the levels found in the water column, which in turn are over an order of magnitude higher than environmental levels proposed to limit eutrophication in rivers. The profiles demonstrated an average net release of SRP and NH4 + from the settling pond sediment to the overlying water of 58mgm−2 d−1 (±32mgm−2 d−1 (1sd)) and 16mgm−2 d−1 (±25mgm−2 d−1 (1sd)), respectively. The DET SO4 2− concentration profiles revealed that the sediment was anoxic within 2cm of the SWI. Dredging of the reed bed made no significant difference to the P release characteristics across the SWI. The EPC0s were much lower than the SRP concentration of the overlying water, indicating that the sediment had the potential to act as a phosphate sink. The apparent contradiction of the DET and EPC0 results is attributed to the fact that DET measurements are made in situ, where as EPC0 measurements are ex situ. These results show that substantial releases of P can occur from wetland sediments, and also highlight the need for caution when interpreting ex situ EPC0 analytical results. [Copyright &y& Elsevier]

Abstract: Sedimentation ponds are widely believed to act as a primary removal process for phosphorus (P) in nutrient treatment wetlands. High frequency in-situ P, ammonium (NH4 +) and dissolved oxygen measurements, alongside occasional water quality measurements, assessed changes in nutrient concentrations and productivity in the sedimentation pond of a treatment wetland between March and June. Diffusive equilibrium in thin films (DET) probes were used to measure in-situ nutrient and chemistry pore-water profiles. Diffusive fluxes across the sediment–water interface were calculated from the pore-water profiles, and dissolved oxygen was used to calculate rates of primary productivity and respiration. The sedimentation pond was a net sink for total P (TP), soluble reactive P (SRP) and NH4 + in March, but became subject to a net internal loading of TP, SRP and NH4 + in May, with SRP concentrations increasing by up to 41μM (1300μl−1). Reductions in chlorophyll a and dissolved oxygen concentrations also occurred at this time. The sediment changed from a small net sink of SRP in March (average diffusive flux: −8.2μmolm−2 day−1) to a net source of SRP in June (average diffusive flux: +1324μmolm−2 day−1). A diurnal pattern in water column P concentrations, with maxima in the early hours of the morning, and minima in the afternoon, occurred during May. The diurnal pattern and release of SRP from the sediment were attributed to microbial degradation of diatom biomass, causing reduction of the dissolved oxygen concentration and leading to redox-dependent release of P from the sediment. In June, 2.7mol-Pday−1 were removed by photosynthesis and 23mol-Pday−1 were supplied by respiration in the lake volume. SRP was also released through microbial respiration within the water column, including the decomposition of algal matter. It is imperative that consideration to internal recycling is given when maintaining sedimentation ponds, and before the installation of new ponds designed to treat nutrient waste. [Copyright &y& Elsevier]

IVF programmes generally follow treatment protocols that strive for best outcomes. Deviations from such established protocols, even if conceptionally well supported, always risk potentially adverse effects on pregnancy chances. Successful pregnancy represents, however, the principal motivation for all fertility treatments. As a universal medical principle, patients are, therefore, entitled to maximal professional efforts towards their desired outcomes in the safest, quickest and most cost-effective ways. For IVF this means, as multiple patient queries in the literature have demonstrated, the following parameters in this order of importance: highest possible pregnancy rates, lowest possible risks, shortest possible time and lowest possible cost. Some recently widely propagated changes to broadly utilized practice patterns in IVF now, post factum, have been determined to be clinically useless and, in addition, have been shown to adversely affect pregnancy chances. Also post factum, this has led to the acknowledgement that significant modifications to established IVF practice should be introduced with caution. In view of the quite satisfactory IVF pregnancy rates that are currently achieved, the uncontrolled introduction of significant protocol modifications, which may adversely affect IVF outcomes, should no longer be acceptable practice as such unproven practice modifications may violate the patient's entitlement to maximally achievable pregnancy rates. [ABSTRACT FROM AUTHOR]

Abstract: The hypothesis that reducing conditions exist in localized zones of high organic matter, termed microniches, was first suggested over a century ago, but only relatively recently have high-resolution techniques been available to investigate them. In any sediment containing benthic fauna, bioturbation affects the distribution of a number of redox-sensitive components. Direct faecal deposition and the death of fauna may be expected to cause particles of labile organic matter (microniches) to be distributed heterogeneously within the sediment. This review discusses the significance and future direction of microniche studies by considering, exclusively, data obtained on a sub-mm scale that provide significant evidence for the existence and properties of microniches. Microelectrodes and planar optodes have shown the significant effect of burrowing organisms on localized O2 distributions and revealed distinct depletions in O2 due to microniches. Localized increases in pCO2 and decreases in pH measured by optodes were attributed to elevated activity at microniches. Diffusive gradients in thin-films have shown isolated supersaturation of metals and sulphide, providing evidence for possible simultaneous oxidation of organic matter by sulphate and iron oxides. The stochastic nature of these data and the lack of information for the same precise location hinders interpretation in terms of sediment diagenesis. If microniches are known to account for a significant proportion of organic matter degradation, re-examination of the current understanding of sedimentary diagenesis may be needed. Further investigation on the distribution and frequency of microniches is required, including a wider range of analytes, in order to estimate their cumulative effect on element diagenesis, immobilisation/remobilisation processes and ultimately pollutant fate. [Copyright &y& Elsevier]

An experimental method is designed to test the Dispersive Extinction Theory (DET). It has been shown that the cosmic redshifl is dependent not only on the distance, but also on the wavelength and the line width. Such dependence is fundamentally different from what was predicted by the Big Bang Theory (BBT) and can be used to test DET experimentally. It has also been shown that a new S-function, instead of the redshift, is solely dependent on distance and independent of wavelength and line width. The issue of line identification for quasars is also discussed according to DET. [ABSTRACT FROM AUTHOR]