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The current investigation provides insights into microstructure development as a function of sintering temperature within lamella walls of ice-templated ceramics, effects of ceramic platelets on wall microstructure, and the influence of those developments on the compressive mechanical response. The results revealed a profound influence of both on the several aspects of ice-templated ceramics, enabling an improved understanding of the structure-mechanical property relationships in these materials and limitations in the development of the ice-templated ceramic structure. In the materials without platelets, at low-temperature walls were highly porous, at intermediate temperature a pore-free lamella wall with fine-grained microstructure developed, and at high-temperature along with grain growth significant abnormal grain growth occurred as well. More dramatic was the combined effects of temperature and platelets. The effects of platelets were realized at two length scales. Some of the platelets developed lamellar bridges, whereas the platelets that became part of the lamella walls remarkably impacted wall microstructure. The current results strongly suggest that there are significant structural and mechanical strength advantages in the incorporation of large anisometric particles in ice-templated ceramics. The addition of large platelets resulted in a marked increase of compressive strength. A significant structural advantage is that the materials containing platelets exhibited improved stability to structural deformation at higher temperatures compared to the materials without the platelets. Thus, this study shows the importance of deeply probing into the structure-mechanical property relationships of ice-templated ceramics as a function of temperature and composition, providing valuable guidance into the microstructure design of these materials.

3D geocellular static models are the key input for fluid flow simulations with the main aim to predict the future reservoir performance for a particular recovery scheme. Since the predictability of the dynamic model depends on the quality of the geocellular model, it is imperative that the input data, the modelling workflow, methodologies and approaches are verified and validated prior to the sanction of the geocellular model. The objective of this paper is therefore to discuss the process of performing quality assurance and quality control (QA/QC) of 3D geocellular models exhibiting real field examples from the Middle East carbonate reservoirs. 3D static models are built using data from multiple sources, at different scales and with different degrees of uncertainty. The validation and reconciliation of all the data is of paramount importance. The procedure to build any geological model is very similar provided all the data is available. Some variations in the procedure are expected depending on the complexity of the phenomena to model, but must of the time workflows divert based on data quality and data availability. In this paper we discuss the use of key validation checks for each step of the modelling process taking into account the data quality and field maturity, namely for the 1)- structural framework modelling, 2)- facies modelling, 3)- porosity modelling, 4)- permeability modelling, 5)- rock type modelling, 6)- water saturation modelling, 7)- upscaling and 8)- uncertainty analysis. The use and validation of the applicability of secondary variables in the petrophysical modelling, such as acoustic impedance from seismic inversion, is also addressed. From the analysis of multiple geocellular models, inconsistencies were detected at different stages of the modelling process, starting from the well surveying with implications to horizontal well positioning within the framework, to the modelling of facies and petrophysical properties, with inconsistencies on variogram model parameters. Also, the validation of the velocity modelling and time-depth conversion used for the structural framework was validated by comparing FWLs depths against spill points. Furthermore, the quality of the facies model could be verified against regional facies belt maps (similar variogram azimuths are expected) while the validation of the permeability scale-up at well level could be achieved by reconciling with well test kh data. These are just a few examples of the material discussed in this paper. The novelty of the quality assurance process pertained to 3D geological models is the identification of appropriate metrics with key performance indicators for each step in the modelling workflow. At the end of the QA/QC process the models are ranked in quality and technical gaps identified for subsequent model improvement. Guidelines and best practices are also presented in this paper.

Mixing supramolecular gels based on enantiomers leads to re-arrangement of gel fibers at the molecular level, which results in more favorable packing and tuneable properties. Bis(urea) compounds tagged with a phenylalanine methyl ester in racemic and enantiopure forms were syn-thesized. Both enantiopure and racemate compounds formed gels in a wide range of solvents and the racemate (1-rac) formed a stronger gel network compared to the enantiomers. The gel (1R+1S) obtained by mixing equimolar amount of enantiomers (1R and 1S) showed enhanced mechanical and thermal stability compared to enantiomers and racemate gels. The preservation of chirality in these compounds was analyzed by circular dichroism and optical rotation measurements. Analysis of the SEM and AFM images revealed that the network in the mixed gel is a combination of enantiomers and racemate fibers, which was further supported by solid state NMR. The analysis of the packing in xerogels by solid state NMR spectra and the existence of twisted-tape morphology in SEM and AFM images confirmed the presence of both self-sorted and co-assembled fibers in mixed gel. The enhanced thermal and mechanical strength may be attributed to the enhanced intermolecular forces between the racemate and enantiomer and the combination of both self-sorted and co-assembled enantiomers in the mixed gel., We thank University of Iceland Research Fund for financial support. D.G. thanks University of Iceland for the Doctoral Research grant and Z.K. thanks University of Ljubljana for the Erasmus exchange program. We thankfully acknowledge Dr. A. Rawal, The Mark Wainwright Analytical Centre, UNSW for solid state NMR studies and Dr. Sigrídur Jónsdóttir, University of Iceland for solution NMR and Mass spectroscopy. P.T. thanks the Australian Research Council for an ARC Centre of Excellence grant (CE140100036) and A.D.M. thanks the National Health and Medical Research Council for a Dementia Development Research Fellowship (APP1106751). L.F. and A.V. thank the FCT (UID/BIO/04469/2013), COMPETE 2020 (POCI-01-0145-FEDER-006684), and Norte2020 Programa Operacional Regional do Norte (BioTecNorte operation, NORTE-01-0145-FEDER-000004) for rheological studies. The rheological study was supported by a STSM Grant from COST Action CM1402 Crystallize., info:eu-repo/semantics/publishedVersion

Polymeric composite insulators consisting of core fiber reinforced polymer insulators covered with polydimethylsiloxane (PDMS) housing are now replacing conventional ceramic insulators especially for high-outdoor power transmission lines due to some specific advantages. Unlike ceramics, polymers have relatively shorter life. Outdoor insulators experience different electrical, mechanical, chemical, and thermal stresses during service. The long-term service performance of these insulators and their service life estimation is an important issue, but it is complicated and time-consuming. The objective of the present investigation is to check the rate of property deterioration during service and to find the approximate lifetime. Working insulators with different ages were collected from service, and the changes in mechanical and electrical properties and hydrophobicity of the PDMS cover against aging time were measured. The service life estimated from the change in mechanical properties and surface hydrophobicity (using MATLAB software) was compared with the service life of a new compound subjected to accelerated aging tests. Prediction of service life is helpful for replacement of aged insulators from service to avoid interruption in power transmission.

In this work, several normally dispersive highly nonlinear chalcogenide optical fibers (NDHNCFs) with a step-index profile have been designed and optimized in view of efficient parabolic pulse (PP) generation. A typical NDHNCF is selected such that the group velocity dispersion is highest among them and the corresponding nonlinearity is also very high. The input pulse parameters are optimized to find the lowest possible optimum length (Lopt) of the fiber where the linearly chirped PP is obtained. Further, it is found that for a shorter input pulse width, PP can be generated at a sufficiently smaller length of the NDHNCF with a slight compromise for its misfit parameter. A detailed analysis of the effect of pre-chirping helps to identify the suitable amount of initial chirp for different chalcogenide fibers with a choice of input pulse parameters. Although no improvement in PP generation is found for normal and initially chirped hyperbolic secant pulses, a highly efficient triangular pulse is achieved for a particular value of input pulse energy and the initial chirp parameter. Finally, the comparative study substantiates that our optimized NDHNCF is capable enough to generate quality PP at a length almost 70% shorter than a standard silica-based fiber.

Set $ A := Q/({\bf z}) $, where $ Q $ is a polynomial ring over a field, and $ {\bf z} = z_1,\ldots,z_c $ is a homogeneous $ Q $-regular sequence. Let $ M $ and $ N $ be finitely generated graded $ A $-modules, and $ I $ be a homogeneous ideal of $ A $. We show that (1) $ \mathrm{reg}\left( \mathrm{Ext}_A^{i}(M, I^nN) \right) \le \rho_N(I) \cdot n - f \cdot \left\lfloor \frac{i}{2} \right\rfloor + b \mbox{ for all } i, n \ge 0 $, (2) $ \mathrm{reg}\left( \mathrm{Ext}_A^{i}(M,N/I^nN) \right) \le \rho_N(I) \cdot n - f \cdot \left\lfloor \frac{i}{2} \right\rfloor + b' \mbox{ for all } i, n \ge 0 $, where $ b $ and $ b' $ are some constants, $ f := \mathrm{min}\{ \mathrm{deg}(z_j) : 1 \le j \le c \} $, and $ \rho_N(I) $ is an invariant defined in terms of reduction ideals of $ I $ with respect to $ N $. There are explicit examples which show that these inequalities are sharp., Comment: 14 pages, updated version, to appear in Journal of Algebra

Three different silica based normal dispersion fibers are designed to identify the best possible one for efficient parabolic pulse generation. Two of them resemble commonly used single core fibers and optimized in such a way that one has lower dispersion and nonlinear coefficient whereas the other possesses higher dispersion and lower nonlinearity. A silica based multi-cladded highly nonlinear fiber (ND-HNLF) is designed as well by successfully restricting its effective area to a very lower value. The comparative analysis among the three fibers suggests that the ND-HNLF would be the best choice for fiber optic manufacturers for parabolic similariton formation due to its smaller optimum length, no effect of higher order dispersion, high nonlinearity and less input power requirement. From our proposed ND-HNLF, a highly nonlinear dispersion decreasing fiber (HN-NDDF) is also designed and optimized by properly varying different fiber parameters as a function of fiber length. Our study also reveals that the HN-NDDF with a typical property of virtual gain would be beneficial for producing parabolic self-similar pulses at smaller optimum lengths with adequate spectral broadening in comparison to that of ND-HNLF.

In order to supplement the need for alternative energy resources within the near future, enhancing the production of biohydrogen with immobilized Clostridium beijerinckii NCIMB8052 was investigated. Magnetite nanoparticles were functionalized, with chitosan and alginic acid polyelectrolytes using a layer-by-layer method, to promote bacterial attachment. Cultivating C. beijerinckii with these nanoparticles resulted in a shorter lag growth phase and increased total biohydrogen production within 100-ml, 250-ml and 3.6-L reactors compared with freely suspended organisms. The greatest hydrogen yield was obtained in the 250-ml reactor with a value of 2.1 ± 0.7 mol H2/mol glucose, corresponding to substrate conversion and energy conversion efficiencies of 52 ± 18 and 10 ± 3 %, respectively. The hydrogen yields obtained using the immobilized bacteria are comparable to values found in literature. However, to make this process viable, further improvements are required to increase the substrate and energy conversion efficiencies.

Managers are influenced in their decisions by the information provided by managerial accountants. Two typical examples from textbooks are the irrelevance of sunk costs and, more recently, the affect of knowing the outcome of a decision or revised budget forecast. Individual differences in the cognitive ability of decision makers to use information can lead to systematic differences in judgments. We identify and label one of these individual cognitive differences comprehensive thinking ability: the ability to think about multiple paths, branches or alternatives. Significant comprehensive thinking ability is likely to mitigate systematic differences in judgment in many contexts. We report the results of a series of studies using a variation on the investment trap (sunk cost or irrelevant cost) problem and a probability revision task. The findings suggest that comprehensive thinking ability may also explain other common systematic differences in judgment.

Ceramic materials are commonly used as outdoor insulators for high voltage power transmission lines. Presently these ceramic insulators are replaced by composite polymeric insulators with silicone rubber (PDMS) housing, especially in industrial areas with pollution. Silicone rubber is chosen for housing material because of its excellent aging resistance, electrical properties, tracking resistance, and stable hydrophobicity which in turn control the tracking resistance. However, the material has deficiencies like poor mechanical strength and high cost. To improve the mechanical properties and reduce the cost, silicone rubber is blended with ethylene vinyl acetate copolymer (EVA). The optimum blend composition is found to be PDMS/EVA 60/40 w/w. But in doing so some reduction in hydrophobicity is observed, thus adversely affecting the tracking resistance. To improve hydrophobicity, the addition of nanosilica at the level of 6 phr is found to be the optimum. Thus high performance outdoor insulators can be produced from a PDMS–EVA blend containing 6 phr nanosilica. Different types of accelerated aging tests were performed on the insulator samples to simulate their aging behavior under different real life aging processes.

We report the selective gelation properties of the copper(II) complexes of N-(4-pyridyl)nicotinamide (4PNA). The morphology of the xerogels was examined by scanning electron microscopy (SEM). The correlation between the X-ray powder diffraction (XRPD) pattern of the xerogels and the single crystal structure of the copper(II) acetate complex suggests that the single crystal X-ray data represent a good structural model for the gel fibers, and that gelation arises from the presence of a 1D hydrogen-bonded chain between gelator amide groups and coordinated anions, while the presence of strongly bound water in non-gelator systems results in the formation of more extensively hydrogen-bonded crystalline networks. The selective gelation of all the copper(II) salts compared to the other metal salts may be attributed to the Jahn–Teller distorted nature of copper(II), which weakens water binding in all copper(II) salts.

Roadside transitory water bodies being manmade depressions have a great ecological and socio-economic importance from years. The effects of agricultural runoffs, jute retting, macro-phytes infestations and inadequate rainfall in changed climate often degrade transitory water bodies’ environment while the biodiversity have impacted severely because of population pressure, over exploitation and indiscriminate use of fine meshed fishing gears as a whole. Physico-chemical and biological analysis with fish species composition, relative abundance, diversity indices like species richness, evenness and Shannon-Wiener index were carried out for pre-, during and post-jute retting season and for year mean as a whole to assess impact of jute retting on the roadside transitory water body’s environmental health and indigenous fish diversity at Sahebnagar village in Nadia District, India. All the physico-chemical parameters barring biochemical oxygen demand and water transparency remained more or less same or marginally got little changed during those three seasons. As much as 19 native fish species with varied relative abundances and dominances were identified. Jute retting impacted lower native fish diversity indices like Shannon-Wiener index values (1.94 to 2.68) clearly indicated poor to moderate pollution status of the transitory water body in that area during monsoon in particular and throughout the year in general. So we opined there should be some control over the intense jute retting in the road side transitory water bodies for sustainable management of these manmade resources.

Regional aquifers are critical for development of oil/gas fields that need water injection for pressure maintenance. However, modeling of regional aquifer is a difficult task as data acquisition and analyses are primarily focused on hydrocarbon bearing intervals. Also, aquifers are generally regional, whereas the data available is clustered around oil/gas fields with negligible data in the vast areas lying outside the fields of interest. The present study aims at building a regional aquifer model for Abu Dhabi Onshore area integrating all the available data in different scales that may be used in planning future availability of water resources. Most of the oil/gas fields located in Onshore of Abu Dhabi have so far been developed by primary pressure maintenance strategy injecting water obtained from the shallower Late Cretaceous, Paleocene and Eocene aquifers. The main water source reservoirs are Dammam, Umm Er Radhuma and Simsima formations. Despite limited data availability, the study delivered a fit for purpose 3D reservoir model integrating seismic data, regional outcrop analogs and available log and core data. An enormous database containing 4768 wells from 10 most important Fields of onshore Abu Dhabi was used to build the structural framework with the help of regional seismic interpreted surface. Sequence stratigraphic cycles were identified in all the formations considering eustatic curves and correlation using GR-NPHI-RHOB logs. Average layer thickness was designed to be around 20ft in all the reservoir intervals. Input for property model was very limited as logs and cores are generally not acquired in aquifer intervals. Wells with NPHI-RHOB logs were used for estimation of porosity and it was calibrated with limited core porosity data available. Permeability has been computed by fitting functions to Poro-Perm cross-plot and then adding statistical dispersion based on observed core permeability data. Different scenarios of permeability were defined due to the high dispersion in the core data. For dynamic modelling three equilibration regions were setup for the main three aquifers and a common PVT table was used. All the water supply and disposal wells were used in history matching. The high case of permeability was found to honor best the production and injection data. The static model built integrating all available data in different scales is robust. Although limited data availability for property modelling was a major concern, the model did show reasonable history match and is fit for purpose to predict future water supply. A systematic data acquisition plan for these aquifers may be implemented in future to make the current model more reliable. The regional aquifer model of Abu Dhabi Onshore is the first of its kind in the country that incorporates all the available information including seismic interpretation in regional scale to small-scale core data.

To identify the best possible normally dispersive optical fibers (NDF) in view of efficient triangular pulse (TP) generation, the optimization of several passive NDFs are reported in this work. The study shows that TPs, which sustain over a reasonably good fiber length, can be generated at shorter length when higher values of dispersion and nonlinearity are considered. A suitable NDF with high value of dispersion and nonlinearity is chosen and renamed as normally dispersive highly nonlinear fiber (ND-HNLF). The fiber parameters and pulse conditions are optimized here in such a way that the pulse maintains its triangular shape throughout a longer length in transient state. A detail analysis is performed on generation and stability of triangular pulses through the ND-HNLFs in absence and in presence of gain. When compared, the ND-HNLF with gain is found to be preferable due to their lower input power requirement and lesser broadening of the output triangular pulses whereas passive ND-HNLF performs better in terms of formation of TPs at shorter length and sustainability of those pulses over moderately larger fiber length. It is also shown that the suggested fibers, competent enough to generate stable TPs can be potentially applied in the area of optical signal doubling and a new fiber based approach is mentioned as well for saw-tooth pulse formation.

Outer membrane vesicles (OMVs) are secreted by all Gram-ve pathogens. These nano-scale delivery vehicles contain discrete arrays of prokaryotic pathogenic determinants, including a family of low molecular weight (MW) lipidic quorum signaling alkyl-quinolones (AQs). These are synthesized from β-keto-fatty acids and function like primordial lipidic hormones, which regulate numerous pathogenic factors both inter-species and intra-species. Significantly, AQs can also directly exacerbate pathogenesis by cross-kingdom signaling with the host immune, metabolic, and other systems. In Pseudomonas aeruginosa more than 50 AQs are reported; many with pathogenic mechanisms that are largely unknown. Some of these AQs are exclusively associated with OMVs. Accurate characterization of these OMV-AQs may reveal novel mechanism of diseases and Pseudomonas aeruginosa presents an ideal model. Matrix-free laser desorption/ionization mass spectrometry (LDI-MS) technologies enjoy unique advantages in mass spectrometry (MS)-based imaging and low MW analysis. We report single-step isolation of Pseudomonas aeruginosa OMV on inert ceramic filters and high-resolution mass spectrometry (HRMS) analysis of AQs vesicle in situ.

Let $ R $ be a $ d $-dimensional Cohen-Macaulay (CM) local ring of minimal multiplicity. Set $ S := R/({\bf f}) $, where $ {\bf f} := f_1,\ldots,f_c $ is an $ R $-regular sequence. Suppose $ M $ and $ N $ are maximal CM $ S $-modules. It is shown that if $ \mathrm{Ext}_S^i(M,N) = 0 $ for some $ (d+c+1) $ consecutive values of $ i \geqslant 2 $, then $ \mathrm{Ext}_S^i(M,N) = 0 $ for all $ i \geqslant 1 $. Moreover, if this holds true, then either $ \mathrm{projdim}_R(M) $ or $ \mathrm{injdim}_R(N) $ is finite. In addition, a counterpart of this result for Tor-modules is provided. Furthermore, we give a number of necessary and sufficient conditions for a CM local ring of minimal multiplicity to be regular or Gorenstein. These conditions are based on vanishing of certain Exts or Tors involving homomorphic images of syzygy modules of the residue field., 20 pages, Final version after revision, To appear in Glasgow Mathematical Journal

Due to the internationalisation of food production and distribution, there has been a significant increase of food fraud in recent years. Food fraud can have serious health implications, and it occurs when food manufacturers implement unethical practices such as making false label claims as well as using additives and fillers within their products to increase profitability. This has been a serious concern. Meat adulteration was examined using a well-defined proteogenomic annotation, carefully selected surrogate tryptic peptides and high-resolution mass spectrometry. Selected mammalian meat samples were homogenised and the proteins extracted and digested with trypsin. Chromatography was achieved using a 30-min linear gradient along with a BioBasic C8 100 × 1 mm column at a flow rate of 75 µl min-1. The mass spectrometer was operated in full-scan high-resolution and accurate mass using resolving powers of 140,000 and 17,500 (FWHM) in full-scan MS and MS/MS respectively. Data independent acquisition (DIA) mode was used including 12 DIA MS/MS scans to cover the mass range 600-1200 m/z. Methodically in silico analyses of myoglobin, myosin-1, myosin-2 and β-haemoglobin sequences allow for the identification of a species-specific tryptic peptide mass lists and theoretical MS/MS spectra. Following comprehensive MS, MS/MS or DIA analyses, the method was capable of the detection and identification of very specific tryptic peptides for all four targeted proteins for each animal species tested with observed m/z below 3 ppm compared with the theoretical m/z. The analyses were successfully performed with raw and cooked meat. Specifically, the method was capable of detecting 1% (w/w) of pork or horse meat in a mixture before and after cooking (71°C internal temperature).

Fish productivity in oxbow lake is impacted severely due to varied unsustainable anthropogenic practices like over exploitation, indiscriminate use of fine meshed fishing gears, jute retting etc. This particular study was conducted in a semi closed oxbow lake ecosystem in eastern India to assess both the present and sustainable fish productivity based on the data collected through direct catch assessment survey, fishing effort survey and catch per unit effort calculation. Hike in relative abundance values like numbers of fish catch (>3.78 times), catch per gear effort (>2.6 times), fish density (>2.65 times) and fall in relative biomass values like catch per gear effort, catch per unit effort and fish standing biomass (>41%) were observed during monsoon compared to premonsoon due to flooded turbid water from the river Ganga and jute retting processes during monsoon. Jute retting and indiscriminate over fishing of the monsoon made fish production reduced by >50% during post monsoon. The current fish productivity was estimated at 1146.64kg/ ha/year supporting only 23.33% livelihoods of enlisted fishers and about 97.67% of fish production remains unreported every year in the official records of the cooperative society based on the oxbow lake ecosystem indicating inefficient management. Total sustainable production of 285MT (@5MT/ha/year) with total operating capital need of INR 1.00 crore (@INR 0.01716 crore/ha/year) with benefit cost ratio of 4.28 was estimated as the sustainable and replicable basis for promotion of organic aquaculture supporting 100% livelihoods of all fishers and rejuvenating the management of the present oxbow lake ecosystem.

Diabetes Mellitus is caused due to disorders of metabolism and its one of the most common diseases in the world today, and growing. Threshold Based Clustering Algorithm (TBCA) is applied to medical data received from practitioners and presented in this paper. Medical data consist of various attributes. TBCA is formulated to effectually compute impactful attributes related to Mellitus, for further decisions. TBCAs primary focus is on computation of Threshold values, to enhance accuracy of clustering results.

Outer membrane vesicles (OMVs) are secreted by all Gram-ve pathogens. These nano-scale delivery vehicles contain discrete arrays of prokaryotic pathogenic determinants, including a family of low molecular weight (MW) lipidic quorum signaling alkyl-quinolones (AQs). These are synthesized from β-keto-fatty acids and function like primordial lipidic hormones, which regulate numerous pathogenic factors both inter-species and intra-species. Significantly, AQs can also directly exacerbate pathogenesis by cross-kingdom signaling with the host immune, metabolic, and other systems. In Pseudomonas aeruginosa more than 50 AQs are reported; many with pathogenic mechanisms that are largely unknown. Some of these AQs are exclusively associated with OMVs. Accurate characterization of these OMV-AQs may reveal novel mechanism of diseases and Pseudomonas aeruginosa presents an ideal model. Matrix-free laser desorption/ionization mass spectrometry (LDI-MS) technologies enjoy unique advantages in mass spectrometry (MS)-based imaging and low MW analysis. We report single-step isolation of Pseudomonas aeruginosa OMV on inert ceramic filters and high-resolution mass spectrometry (HRMS) analysis of AQs vesicle in situ.

We investigate three cases regarding asymptotic associate primes. First, assume $ (A,\mathfrak{m}) $ is an excellent Cohen-Macaulay (CM) non-regular local ring, and $ M = \operatorname{Syz}^A_1(L) $ for some maximal CM $ A $-module $ L $ which is free on the punctured spectrum. Let $ I $ be a normal ideal. In this case, we examine when $ \mathfrak{m} \notin \operatorname{Ass}(M/I^nM) $ for all $ n \gg 0 $. We give sufficient evidence to show that this occurs rarely. Next, assume that $ (A,\mathfrak{m}) $ is excellent Gorenstein non-regular isolated singularity, and $ M $ is a CM $ A $-module with $\operatorname{projdim}_A(M) = \infty $ and $ \dim(M) = \dim(A) -1 $. Let $ I $ be a normal ideal with analytic spread $ l(I) < \dim(A) $. In this case, we investigate when $\mathfrak{m} \notin \operatorname{Ass} \operatorname{Tor}^A_1(M, A/I^n)$ for all $n \gg 0$. We give sufficient evidence to show that this also occurs rarely. Finally, suppose $ A $ is a local complete intersection ring. For finitely generated $ A $-modules $ M $ and $ N $, we show that if $ \operatorname{Tor}_i^A(M, N) \neq 0 $ for some $ i > \dim(A) $, then there exists a non-empty finite subset $ \mathcal{A} $ of $ \operatorname{Spec}(A) $ such that for every $ \mathfrak{p} \in \mathcal{A} $, at least one of the following holds true: (i) $ \mathfrak{p} \in \operatorname{Ass}\left( \operatorname{Tor}_{2i}^A(M, N) \right) $ for all $ i \gg 0 $; (ii) $ \mathfrak{p} \in \operatorname{Ass}\left( \operatorname{Tor}_{2i+1}^A(M, N) \right) $ for all $ i \gg 0 $. We also analyze the asymptotic behaviour of $\operatorname{Tor}^A_i(M, A/I^n)$ for $i,n \gg 0$ in the case when $I$ is principal or $I$ has a principal reduction generated by a regular element., 34 pages

The depolarization behavior of lead zirconate titanate 95/5 and 52/48 has been well characterized under uniaxial strain with strain rates on the order of 106/s, and under quasi-static uniaxial stress loading with strain rates on the order of 0.1–100/s. This study examines the depolarization behavior under uniaxial stress at strain rates on the order of 10 to 103/s. Specimens were loaded using a split Hopkinson pressure bar. Loading rates from 7.2 to 92.5 MPa/µs were investigated, with a maximum stress of around 900 MPa. The results show significant depolarization rate sensitivity in lead zirconate titanate 52/48, while lead zirconate titanate 95/5 exhibits two responses above and below the stress rate of 50–60 MPa/µs, both with little rate sensitivity.

Microalgae are being investigated as potential candidates for biodiesel production since they can be grown without competition with food production, have an inherently fast growth rate, and can have a high lipid content under different nutrient limiting conditions. However, large scale production will best be carried out with indigenous strains, well adapted to local conditions. This study reports on the characterization of the novel microalga Chlorella sp. PCH90, isolated in Quebec. Its molecular phylogeny was established and lipid production studies as a function of the initial concentrations of nitrate, phosphate, and sodium chloride were carried out using response surface methodology. Under the appropriate conditions this microalga could produce up to 36% lipid and grew well in both synthetic medium and secondary effluent from a wastewater treatment plant at both 22 and 10 °C. Thus, this strain is promising for further development as a potential biofuels producer under local climatic conditions.

The present work deals with the performances of straight and bent active normal dispersion decreasing fibers (NDDFs) to create parabolic pulses. Since these optical fibers are generally kept in the form of fiber rolls, they may suffer from unavoidable bend losses. For the NDDFs, the core radius and hence transverse field distribution inevitably change along the fiber length; thereby bend loss is no longer an invariable quantity throughout the NDDF length. The spatial variation of bend loss for a parabolic index NDDF is incorporated for the first time to investigate the effect of bend loss analytically and numerically on parabolic pulse generation. It is illustrated that suitable choice of relative refractive index difference and bend radius of curvature of the fibers would lead to parabolic pulse formation by a bent NDDF. The comparative study on the straight and bent NDDFs will be helpful for the fiber optic manufacturers to design and fabricate NDDFs with proper choice of optimized parameters and index differences so that parabolic pulses can be generated even under the influence of practically unavoidable bending.

The advantages of thick electrodes in improving energy density at the cell level has been reported in many lithium-ion battery papers. Thick electrodes increase energy density by reducing the fraction of the cell dedicated to inactive components, in particular current collectors and separators. However, thick electrodes increase electron and ion transport path lengths through the electrode which increases cell resistance and can result in limited current densities of battery operation. In this presentation the fabrication and characterization of cells with thick electrodes will be described. These electrodes are produced via hydraulic pressing and mild thermal treatment of active material powders as opposed to conventional casting of composite slurries. These electrodes thus have no binders or conductive additives, which would be expected to increase the diffusion of ions through the electrolyte-impregnated void regions within the electrode. However, these all active material electrodes can now have multiple processes that might limit their rate of charge/discharge, including transport of ions through the electrode microstructure, transport of ions through the solid active material particles, and transport of electrons through the all active material electrode matrix to the current collector. To provide insights into the processes that are limiting the current density in the high energy electrodes, we will describe the use of neutron imaging. Neutron imaging is highly sensitive to the lithium concentration within the battery cell, and thus regions undergoing lithiation/delithiation can be interrogated in operando during charge/discharge of the cell. The lithiation/delithiation profiles provide insights into what process limits the cell and opportunities to improve the performance of these thick electrodes fabricated with less common processing routes.

Mg–Al 2 O 3 nanocomposite powders, with Al 2 O 3 particles of 50 nm size, were synthesized by mechanical alloying starting from a mixture of 70 vol.% pure Mg and 30 vol.% Al 2 O 3 powders. A steady-state condition was obtained on milling the powder mix for about 20 h, when the crystallite size of the Mg powder was about 10 nm. The structural evolution during milling was monitored using scanning electron microscopy, energy dispersive spectrometry, and X-ray diffraction methods. The results showed that a mixture of Mg, Al 2 O 3 , and MgO phases were obtained on mechanical alloying. On annealing the milled powders at 600 °C for 30 min, a displacement reaction occurred between the Mg and Al 2 O 3 phases, when the formation of a mixture of pure Al and MgO phases was observed. Also, a reaction occurred between the initial Mg powder and Al formed as a result of the displacement reaction, leading to the formation of Mg 17 Al 12 , Al 0.58 Mg 0.42 , and Al 3 Mg 2 phases. Thus, the powder annealed after milling the Mg + Al 2 O 3 powder mix for 25 h consisted of Al, MgO and Al 3 Mg 2 phases.

In this paper, we report the potential of junctionless (JL) MOS transistors for ultra low power (ULP) subthreshold logic applications. It is demonstrated that double gate (DG) JL devices, which do not require source or drain extension region engineering, can perform significantly better than conventional inversion mode devices, and comparable with underlap DG MOSFETs for ULP applications. Sensitivity analysis shows that among all device parameters, JL devices exhibit least sensitivity to gate length in comparison with inversion mode and underlap MOSFETs. Results highlight the advantages and challenges of JL transistors for next-generation ULP CMOS logic devices.

Polymeric outdoor insulators derived from polydimethyl siloxane (PDMS) are replacing conventional ceramic insulators in high voltage power transmission lines because of their improved electrical, mechanical and hydrophobic performance. Major impediments like failure of polymeric insulators due to natural aging by UV radiation from sunlight and electrical tracking have limited their usage. Herein, it is demonstrated about the usage of manganese dioxide based nanoparticles as an effective agent to prevent the UV accelerated aging of polymeric insulators. MnO

Let $ R $ be a Cohen-Macaulay local ring. We prove that the $ n $th syzygy module of a maximal Cohen-Macaulay $ R $-module cannot have a semidualizing direct summand for every $ n \ge 1 $. In particular, it follows that $ R $ is Gorenstein if and only if some syzygy of a canonical module of $ R $ has a non-zero free direct summand. We also give a number of necessary and sufficient conditions for a Cohen-Macaulay local ring of minimal multiplicity to be regular or Gorenstein. These criteria are based on vanishing of certain Exts or Tors involving syzygy modules of the residue field., 13 pages

We give a short proof of a result due to Katz and West: Let $R$ be a Noetherian ring and $I_1,\ldots,I_t$ ideals of $R$. Let $M$ and $N$ be finitely generated $R$-modules and $N' \subseteq N$ a submodule. For every fixed $i \ge 0$, the sets $\mathrm{Ass}_R\left( \mathrm{Ext}_R^i(M, N/I_1^{n_1}\cdots I_t^{n_t} N') \right)$ and $\mathrm{Ass}_R\left( \mathrm{Tor}_i^R(M, N/I_1^{n_1}\cdots I_t^{n_t} N') \right)$ are independent of $(n_1,\ldots,n_t)$ for all sufficiently large $n_1,\ldots,n_t$., Comment: 3 pages, revised version

Colossal permittivity (e′ = 301,484 at room temperature and 1 kHz) of barium titanate was induced in ceramics synthesized using the microwave sintering method. Three different sintering processes (conventional, spark plasma, and microwave) were performed to better understand colossal permittivity in sintered barium titanate. The dielectric permittivity measurements revealed that the appearance of colossal permittivity has strong dependence on the sintering temperature and atmosphere, and less on the grain size of the sintered ceramics. However, the as-sintered barium titanate samples produced by microwave sintering show high dielectric loss (tanδ > 1) consistent with oxygen reduction during the microwave sintering process and consequent accumulation of oxygen vacancies and associated charge carriers at the grain boundary. Since the highly conductive state of as-sintered ceramics precludes their use in dielectric applications, thermal annealing at different conditions was performed to recover insulating characteristics. Microwave-sintered barium titanate with post annealing process (950°C for 12 h in air) showed low dielectric loss (tanδ = 0.045) at room temperature and 1 kHz, while still showing a much higher permittivity (e′ = 36,055) than conventionally sintered barium titanate (e′ = 3500).

Hydrogen production from glucose via single-stage photofermentation was examined with the photosynthetic bacterium Rhodobacter capsulatus JP91 (hup-). Response surface methodology with Box–Behnken design was used to optimize the independent experimental variables of glucose concentration, glutamate concentration and light intensity, as well as examining their interactive effects for maximization of molar hydrogen yield. Under optimal condition with a light intensity of 175 W/m 2 , 35 mM glucose, and 4.5 mM glutamate, a maximum hydrogen yield of 5.5 (±0.15) mol H 2 /mol glucose, and a maximum nitrogenase activity of 246 (±3.5) nmol C 2 H 4 /ml/min were obtained. Densitometric analysis of nitrogenase Fe-protein expression under different conditions showed significant variation in Fe-protein expression with a maximum at the optimized central point. Even under optimum conditions for hydrogen production, a significant fraction of the Fe-protein was found in the ADP-ribosylated state, suggesting that further improvement in yields might be possible.

Calculation of bend loss for single-mode graded-index fibers utilizes the fundamental modal field. Using some of the single and two parameter scalar variational approximations available in the literature for this mode, the bend loss has been computed. The exact results are obtained using a well known numerical method. The accuracies of the results obtained from the use of these variational fields have been compared.

This research experimentally examines the favorable/unfavorable outcomes of a firm's financial and nonfinancial performance measures on financial analysts' recommendation to divest or invest in a firm. The participants were financial analysts who made recommendations ranging from “definitely sell” to “hold” to “definitely buy.” The results show that financial and nonfinancial performance measures and their favorableness have an interactive impact on analysts' recommendations. To be precise, the recommendations were very close to the “definitely sell” anchor when the performance was unfavorable, irrespective of whether the measures presented were financial or nonfinancial. Further, favorableness of performance on nonfinancial measures appears to be irrelevant when performance on financial measures is unfavorable. However, when performance on financial measures is favorable, the effect of nonfinancial performance had a differential effect on analysts' recommendations depending on whether these measures indicated favorable or unfavorable performance. Specifically, when nonfinancial performance was unfavorable, the recommendations were closer to “hold” on average, but the recommendations were closer to “definitely buy” on average when nonfinancial performance was favorable. These results are consistent with our expectations. Overall, given that more and more firms are disclosing nonfinancial measures along with the traditional financial measures, and with an increasing number of firms reporting unfavorable financial performance, the results of this research underline the importance of considering both financial and nonfinancial measures and their outcomes—favorable and unfavorable—on analysts' recommendations. Data Availability: Please contact the authors.

Barium titanate-20wt% cobalt ferrite (BaTiO{sub 3}-20wt%CoFe{sub 2}O{sub 4}) nanocomposites were sintered from nanocrystalline BaTiO{sub 3} and CoFe{sub 2}O{sub 4} powders using spark plasma sintering (SPS) and pressureless sintering (PS) techniques. Using SPS, dense polycrystalline composites were obtained at a sintering temperature as low as 860 C and a time of 5 min whereas PS required a higher sintering temperature (1150 C) and time (120 min) to obtain similarly dense composites. Microstructural analysis of the composites showed that both the techniques retained nanocrystalline grain sizes after sintering. High resolution X-ray diffraction measurements revealed that the BaTiO{sub 3}-20wt%CoFe{sub 2}O{sub 4} composites sintered by the SPS technique did not exhibit formation of any new phase(s) due to reaction between the BaTiO{sub 3} and CoFe{sub 2}O{sub 4} phases during sintering. However, the PS technique resulted in the formation of additional phases (other than the BaTiO{sub 3} and CoFe{sub 2}O{sub 4} phases) in the composites. While the composites synthesized by SPS were of superior phase-purity, evidence of Fe diffusion from the spinel to the perovskite phase was found from X-ray diffraction and permittivity measurements.

Biological hydrogen production presents a possible avenue for the large scale sustainable generation of hydrogen needed to fuel a future hydrogen economy. Amongst the possible approaches that are under active investigation and that will be briefly discussed; biophotolysis, photofermentation, microbial electrolysis, and dark fermentation, dark fermentation has the additional advantages of largely relying on already developed bioprocess technology and of potentially using various waste streams as feedstock. However, the major roadblock to developing a practical process has been the low yields, typically around 25%, well below those achievable for the production of other biofuels from the same feedstocks. Moreover, low yields also lead to the generation of side products whose large scale production would generate a waste disposal problem. Here recent attempts to overcome these barriers are reviewed and recent progress in efforts to increase hydrogen yields through physiological manipulation, metabolic engineering and the use of two-stage systems are described.

Replacement of fossil fuels with alternative energies is increasingly imperative in light of impending climate change and fossil fuel shortages. Biohydrogen has several potential advantages over other biofuels. Dark fermentation as a means of producing biohydrogen is attractive since a variety of readily available waste streams can be used. However, at present its practical application is prevented by the low yields obtained. Here the basic metabolisms leading to hydrogen production are outlined and current research to increase yields, either through modification of existing pathways, or by metabolic engineering to create new, higher yielding, pathways, is discussed. Inactivation of competing reactions and manipulation of culture conditions has lead to higher hydrogen yields, near those predicted by metabolic schemes. However, to be useful, hydrogen production must be increased beyond present limits. Several possibilities for surpassing those limits using metabolic engineering are presented.

Biodiesel manufacture produces crude glycerol as a major byproduct. At the scale estimated for future biodiesel production, extensive quantities of crude glycerol fraction will be generated, creating a large waste stream with potentially significant environmental impacts. The magnitude of projected future crude glycerol supplies suggests that its conversion to a biofuel is the only viable route to producing a product that does not cause market saturation. Previously it was shown that crude glycerol could be converted to hydrogen, a possible future clean energy carrier, by photofermentation using Rhodopseudomonas palustris through photofermentation. Here, the effects of nitrogen source and different concentrations of crude glycerol on this process were assessed. At 20 mM glycerol, 4 mM glutamate, 6.1 mol hydrogen/mole of crude glycerol were obtained under optimal conditions, a yield of 87% of the theoretical, and significantly higher than what was achieved previously.

The extent of dislocation-based plasticity in ceramics is limited and often accompanied by microcracking. This limitation has precluded the investigation of post-yield plastic response in ceramics. Using low-load nanoindentations and by tracking the hardness of selected grains before and after plastic deformation, the influence of microcracking and variability in microhardness due to grain orientation were minimized and the post-yield response of polycrystalline ZrB 2 ceramic was determined. The observed increase in nanoindentation hardness after plastically deforming isolated ZrB 2 grains indicates conclusively the existence of post-yield strain hardening.

Photosynthetic bacteria have been extensively investigated for biohydrogen production due to their high intrinsic substrate conversion efficiency. Many studies have examined different aspects of photo fermentative hydrogen production using various volatile organic fatty acids under nitrogen limited conditions, and in some cases nearly stoichiometric hydrogen yields have been obtained. In addition, there has been great interest in using photosynthetic bacteria to increase the yields of dark fermentation of glucose through either two stage or co-culture approaches. Although these processes can achieve yields of about 7 mol of H2 per mole of glucose, there have many drawbacks. Thus, we have begun the systematic investigation of a simple one stage system for the conversion of glucose to hydrogen through photofermentation by Rhodobacter capsulatus. Yields of about 3 mol of H2 per moles of glucose have been obtained, which represents a yield of 25% yield. Thus improvement is needed and can be sought through a variety of means, including. process optimization and gene inactivation. These approaches could allow the development of a single stage process for the complete stoichiometric conversion of glucose, or glucose containing wastes, to hydrogen with a minimal lag phase and relative insensitivity to inhibition by fixed nitrogen. This would present an attractive simple alternative to either two stage or co-culture fermentations for the complete conversion of carbohydrate substrates to hydrogen.

The purpose of this study was to prepare low molecular weight alginic acid (LMWA) nanoparticles by cation-induced, controlled gelification of depolymerized alginic acid for effective drug delivery to drug resistant bacteria. The depolymerization reaction was performed using potassium persulfate oxidation at an optimized condition. The optimized conditions for depolymerization were anticipated to be 37°C, pH 4, 2 days reaction time, and a 0.075 M concentration of potassium persulphate containing 0.001 M silver nitrate in the final reaction mixture. Gel permeation chromatography showed depolymerized alginic acid had an average molecular weight of 20.95 ± 0.49 kDa. Depolymerized alginic acid was also characterized for its structural integrity by X-ray diffraction, nuclear magnetic resonance, and Fourier transform spectroscopy. Depolymerized alginic acid was used to prepare low molecular weight nanoparticles with a particle size of 54 ± 0.41 nm, and a zetapotential of −32.2 ± 3.91 mV. The nanoparicles were then subjected to tetracycline loading. In vitro drug loading and drug release efficiencies after 100 h were determined to be 66.56 ± 1.88 and 61.8 ± 0.141%, respectively. Finally, the minimal inhibitory concentration and a putative mode of action for the tetracycline nanoparticles were determined using tetracycline resistant bacteria, Escherichia coli XL-1.

The parabolic similariton pulse formation by alternate arrangements of passive and active dispersion compensating fibers (DCFs) is presented here. These combinations of passive and active DCFs with constant core radii and constant nonlinearities are suggested as equivalent profiles of a dispersion tailored fiber amplifier in normal dispersion regime. The dispersion tailored fibers, usually known as dispersion decreasing fibers (DDFs) in normal dispersion regime, are capable of producing linearly chirped parabolic self-similar pulses. The DDF is designed and optimized with proper choice of fiber parameters so that considerable variation of nonlinearity can be achieved, which in turn enhances the effective gain coefficient of the fiber. Inclusion of this nonlinear variation along the DDF amplifier length leads to obtain the simulated output pulses with very small misfit parameters with respect to perfect parabolic pulse at sufficiently reduced optimum length. At the same time to avoid the fabrication difficulties of the DDF, the alternately arranged passive and active DCFs are suggested as suitable alternatives of the DDF. The performances of the cascaded systems for generation of self-similar parabolic pulses are compared with that of the DDF amplifier as well as combined systems consisting of DCFs with equal gain. The results show that the proposed alternately arranged cascaded system with less pumping requirements, are efficient enough to produce similar parabolic pulses as compared to the previously designed DDF, even when considerable amount of splice loss at each joint is included.

Macroscopic manifestation of microscale plasticity at room temperature in the form of slip-lines has been elusive in brittle solids. Recently, such a phenomenon has been reported in ZrB2 ceramics and ZrB2–SiC composites, where slip-lines were detected in room-temperature deformation. Here we show that the slip-line spacing increases with grain size in these ceramics and their composites. Such behavior has been rationalized on the basis of geometrically necessary dislocations and the role of grain boundaries and interfaces.