Miracle-dz/UniFAR-FTUs huggingface dataset:
Weyl spectra of operator matrices

In this paper it is shown that if MC = ( iS a 2 x 2 upper triangular operator matrix acting on the Hilbert space 7H E IC and if W(.) denotes the "Weyl spectrum", then the passage from w(A) U w(B) to w(MC) is accomplished by removing certain open subsets of w(A) n w(B) from the former, that is, there is equality w(A) U w(B) = w(MC) U G, where G is the union of certain of the holes in w(Mc) which happen to be subsets of w (A) n w (B). Let At and IC be Hilbert spaces, let 1C(7-, 1C) denote the set of bounded linear operators from 7t to IC, and abbreviate LC(QH,7) to C(H). When A E LC(t) and B E L(/C) are given we denote by Mc an operator acting on 1t E 1C of the form M A C) Mc:=( 0 ), where C E iC(! , 7-). The invertibility and spectra of Mc were considered by Du and Jin [5]. In this paper we give some conditions for operators A and B to exist an operator C such that Mc is Weyl, and describe the Weyl spectra of Mc. Recall ([7], [8]) that an operator A E 12(X, Y) for Banach spaces X and Y is called regular if there is an operator A' E L(Y, X) for which A = AA'A; then A' is called a generalized inverse for A. In this case, X and Y can be decomposed as follows (cf. [8, Theorem 3.8.2]): A-1(0) e A'A(X) = X and A(X) e (AA')-'(0) = Y. It is familiar ([6], [8]) that A E LC((, IC) is regular if and only if A has closed range. An operator A E LC(7-, IC) is called relatively Weyl if there is an invertible operator A' E 12(IC,7t) for which A = AA'A. It is known ([8, Theorem 3.8.6]) that A is relatively Weyl if and only if A is regular and A-1(0) A(H)', where means a topological isomorphism between spaces. An operator A E LQ(H, IC) is called left-Fredholm if it is regular with finite dimensional null space and rightFredholm if it is regular with its range of finite co-dimension. If A is both leftand right-Fredholm, we call it Fredholm. The index, ind A, of a leftor right-Fredholm Received by the editors November 21, 1997 and, in revised form, May 1, 1998 and March 10, 1999. 1991 Mathematics Subject Classification. Primary 47A53, 47A55.
An accurate and self-consistent chemical abundance catalogue for the APOGEE/Kepler sample

Context. The APOGEE survey has obtained high-resolution infrared spectra of more than 100,000 stars. Deriving chemical abundances patterns of these stars is paramount to piecing together the structure of the Milky Way. While the derived chemical abundances have been shown to be precise for most stars, some calibration problems have been reported, in particular for more metal- poor stars. Aims. In this paper, we aim to (1) re-determine the chemical abundances of the APOGEE+Kepler stellar sample (APOKASC) with an independent procedure, line list and line selection, and high quality surface gravity information from astroseismology, and (2) extend the abundance catalogue by including abundances that are not currently reported in the most recent APOGEE release (DR12). Methods. We fixed the Teff and log g to those determined using spectrophotometric and asteroseismic techniques, respectively. We made use of the Brussels Automatic Stellar Parameter (BACCHUS) code to derive the metallicity and broadening parameters for the APOKASC sample. In addition, we derived differential abundances with respect to Arcturus. Results. We have validated the BACCHUS code on APOGEE data using several well-known stars, and stars from open and globular clusters. We also provide the abundances of C, N, O, Mg, Ca, Si, Ti, S, Al, Na, Ni, Mn, Fe, K, P, Cr, Co, Cu, Rb, Yb and V for every star, line, and show the impact of line selection on the final abundances. These include abundances of five new elements and improved abundances for Si, Ti, S, and V. Conclusions. In this paper, we present an independent analysis of the APOKASC sample and provide abundances of up to 21 elements. This catalogue can be used not only to study chemical abundance patterns of the Galaxy but also to train data driven spectral approaches which can improve the abundance precision in a restricted dataset, but also full APOGEE sample.
The Role of Trade Credit in the Spanish Agrogood Industry

Trade credit is an important way of firm financing. Its habitual practice and the excessive enlargement of the payment periods deteriorate profitability of firms and even could affect the performance of the financial system. In spite of the relevance of this issue there are few empirical researches with Spanish firms. This work intends to fill this gap and to shed light on the factors related to the extension of trade credit in a set firms of the agrofood industry. In the theoretic and empirical literature different motives have been proposed to explain the extension of trade credit: a mechanism to reduce transaction costs, a financial alternative to the bank system and an additional tool to improve commercial activities. To contrast these ideas a panel of 388 firms for the period 1998-2005 has been taken, and static and dynamic regression models have been estimated by using robust methods to heteroskedasticity, autocorrelation and endogeneity of the explanatory variables. The results confirm that trade credit receivable is associated with more active firms and with cheaper bank financing. Furthermore, a negative link with the size of the firm and a positive relationship with short-term liabilities, accounts payable and bank debts, are encountered. These findings are consistent with commercial perspectives, rather than a pure financial view, in the sense that small and financial distressed producers extend trade credit as a way of promoting products and increasing sales.
ALMA Observations of Molecular Clouds in Three Group-centered Elliptical Galaxies: NGC 5846, NGC 4636, and NGC 5044

We present new ALMA CO(2–1) observations of two well-studied group-centered elliptical galaxies: NGC 4636 and NGC 5846. In addition, we include a revised analysis of Cycle 0 ALMA observations of the central galaxy in the NGC 5044 group. We find evidence that molecular gas is a common presence in bright group-centered galaxies (BGG). CO line widths are broader than Galactic molecular clouds, and using the reference Milky Way XCO, the total molecular mass ranges from 2.6 × 105 M⊙ in NGC 4636 to 6.1 × 107 M⊙ in NGC 5044. Complementary observations using the ALMA Compact Array do not exhibit any detection of a CO diffuse component at the sensitivity level achieved by current exposures. The origin of the detected molecular features is still uncertain, but these ALMA observations suggest that they are the end product of the hot gas cooling process and not the result of merger events. Some of the molecular clouds are associated with dust features as revealed by HST dust extinction maps, suggesting that these clouds formed from dust-enhanced cooling. The global nonlinear condensation may be triggered via the chaotic turbulent field or buoyant uplift. The large virial parameter of the molecular structures and correlation with the warm ( )/hot (≥106) phase velocity dispersion provide evidence that they are unbound giant molecular associations drifting in the turbulent field, consistent with numerical predictions of the chaotic cold accretion process. Alternatively, the observed large CO line widths may be generated by molecular gas flowing out from cloud surfaces due to heating by the local hot gas atmosphere.
Chemical Composition, Antioxidant Potential, and Antibacterial Activity of Essential Oil Cones of Tunisian Cupressus sempervirens

The extraction yield of the essential oil (EO) extracted by hydrodistillation from the cones of Tunisian Cupressus sempervirens L. was of 0.518%. The chemical composition was analyzed by GC-MS. Results showed that this essential oil was mainly composed of monoterpene hydrocarbons (65%) with α-pinene as the major constituent (47.51%). Its antioxidant activity was ascertained by evaluating the total antioxidant capacity and also by evaluating its inhibitory effect against DPPH and ABTS radicals. In addition, it showed a strong antioxidant power against the DPPH (IC50 = 151 µg/mL) and ABTS (IC50 = 176.454 µg/mL) radicals scavenging. Moreover, its antibacterial activity was tested against different species of pathogenic bacteria (three Gram-positive and eight Gram-negative bacteria). The bacterial strains susceptible to the evaluated oil were Bacillus subtilis, Escherichia coli, Klebsiella oxytoca, Morganella morganii, Shigella, and Vibrio cholerae.
Dairy By-products Valorization with Biomethane and Biohydrogen Production Through Lactose Fermentation in Anmbr

Dairy liquid by-products after cheese production (e.g. whey for hard cheese, “scotta” for ricotta, brine for mozzarella, lactose syrup after milk standardization by ultrafiltration) represent a potential revenue for food factories where large scale industrial production is implemented, as additional ingredients may be recovered, transformed and sold. Still, these by-products may also represent a problem for small/medium size factories or in areas that are far from ingredients transformation platforms: complete processing of small volumes or shipping liquids over long distances is not convenient. By-products are often disposed as waste, generating unproductive cost for the factory and worsening environmental footprint. In this paper a simple closed loop solution is evaluated for full valorization of by-products, based on the technologies of protein separation/concentration and anaerobic treatment of the lactose solution. Whey proteins are separated by ultrafiltration and can be reused in the cheese process or converted locally into fresh animal feed. Application studies will be presented. Ultrafiltration permeate (filtrate) is a diluted lactose syrup that is used as raw material for fermentation. Lactose dark fermentation for hydrogen production has been documented on a laboratory scale, but not really tested before on a semi-industrial scale. Results obtained from both laboratory scale and semi-industrial scale fermenter will be presented. Finally, anaerobic membrane digester has been evaluated on a semi-industrial scale to convert all residual lactose into biomethane, that can be efficiently reused in the dairy factory boiler for steam production. Anaerobic membrane digester proved to be a valuable solution, as it allows maximum lactose conversion efficiency with good quality liquid effluent.
Digestibility of Nutrients and Aspects of the Digestive Physiology of the Greater Cane Rat, Thryonomys swinderianus in Two Seasons

The greater cane rat, Thryonomys swinderianus, utilizes high fibrous plant material and is an important meat source in West Africa. An insight in its digestive physiology will enhance our understanding of its feeding habits. Digestibility coefficients of the food were determined during two seasons before the animals were euthanased. The distribution and concentrations of nutrients and energy in different parts of the gastrointestinal tract were determined at the time of day when animals practised coprophagy. Trial 1 diet in the wet season consisted of 36% neutral detergent fibre (NDF), 11% protein and 49% dry matter, while the Trial 2 diet in the dry season consisted of 53% NDF, 8–9% protein and 89% dry matter. The Trial 2 animals on the poor diet increased their daily nutrient intake, possibly increased the volume of digesta and practised frequently cophrophagy, so that faecal production was reduced and digestibility coefficients were relatively high. Coprophagy increased both protein and energy intake as soft pellets in the distal colon had higher protein and energy content than the hard faeces. Energy, protein and acid-detergent fibre were retained in the caecum of Trial 1 females and the caecum and proximal colon of the Trial 2 animals 16 hours after feeding, illustrating the importance of these two regions in the fermentation process. Water was absorbed in the distal colon as dry matter content of digesta increased 53%, 4% and 56% from the proximal colon to the distal colon. Animals produced hard faeces with only 16% and 5% lower moisture content in the dry season, compared to that produced in the wet season, as water was not a limiting factor during the trials. It was concluded that an increase in daily food intake, an increase in coprophagy and the presence of a colonic separation mechanism (that retains small particles) enable the greater cane rat to utilize high fibrous plant material. These digestive strategies seem to be comparable to those observed in other hystricomorph rodents.
Visible Light-Driven Water Oxidation Catalyzed by Ruthenium Complexes

A shift in energy dependence from fossil fuels to sustainable and carbon-neutral alternatives is a daunting challenge that faces the human society. Light harvesting for the production of solar fuels has been extensively investigated as an attractive approach to clean and abundant energy. An essential component in solar energy conversion schemes is a catalyst for water oxidation. Ruthenium-based catalysts have received significant attention due to their ability to efficiently mediate the oxidation of water. In this context, the design of robust catalysts capable of driving water oxidation at low overpotential is a key challenge for realizing efficient visible light-driven water splitting. Herein, recent progress in the development within this field is presented with a focus on homogeneous ruthenium-based systems and surface-immobilized ruthenium assemblies for photo-induced oxidation of water. and are fundamental for designing WOCs with improved catalytic efficiencies.
Effects of non-steroidal gonadal factors on LH secretion in female common carp during the reproductive cycle

The aim of this study was to evaluate the effects of recombinant human inhibin A, recombinant human activin A and desteroidized ovarian extract on LH secretion in vitro and in vivo in female common carp during different stages of reproductive cycle. Inhibin stimulated spontaneous as well as GnRH-stimu - lated LH release in vitro in fish during gonadal recrudescence. This hormone did not have an influence on spontaneous LH secretion in the periovulatory period, but had a slightly inhibitory effect on GnRH-stimu - lated LH release in this stage of gonad maturity. Activin decreased spontaneous LH secretion during gonadal recrudescence and increased LH secretion before ovulation, having no effects on GnRH-stimulated LH release during both stages of gonad maturity. The desteroidized ovarian extract failed to modify spontaneous LH secretion, but decreased GnRH-stimulated LH release during recrudescence and especially before ovulation. It is to conclude that these data suggest the differential role of inhibin/activin as substances in the regulation of LH secretion in common carp females.
Dual-Band Negative Group Delay Circuit Using λ/4 Composite Right/Left-Handed Short Stubs

In this paper, a novel design for a dual-band negative group delay circuit (NGDC) is proposed. Composite right/left-handed (CRLH) λ/4 short stubs are employed as a dual-band resonator. A CRLH λ/4 short stub is composed of a typical transmission line element as the right-handed component and a high-pass lumped element section as the left-handed component. It is possible to simultaneously obtain open impedances at two separate frequencies by the combination of distinctive phase responses of the right/left-handed components. Negative group delay (NGD) can be obtained at two frequencies by using dual-band characteristics of the CRLH stub. In order to achieve a bandwidth extension, the proposed structure consists of a two-stage dual-band NGDC with different center frequencies connected in a cascade. According to the experiment performed, with wide-band code division multiple access (WCDMA) and worldwide interoperability for microwave access (WiMAX), NGDs of ? 3.0±0.4 ㎱ and ? 3.1±0.5 ㎱ are obtained at 2.12～2.16 ㎓ and 3.46～3.54 ㎓, respectively.
Haulout patterns of Saimaa ringed seals and their response to boat traffic during the moulting season

Conservation of the Critically Endangered ringed seal Phoca hispida saimensis pop- ulation in Lake Saimaa in Finland requires broader knowledge of the behavioural ecology of this subspecies. Understanding Saimaa ringed seal haulout patterns and their response to boat traffic is crucial for designing sustainable land use and tourism guidelines. Responses of unidentified seals to small outboard motor boat traffic were studied during the moulting season. The median distance at which the seals responded to an approaching boat was 240 m. GPS-phone tags were used to study both circadian and seasonal haulout behaviour patterns of individual seals (n = 8) during the open-water season. The average post-moulting haulout duration was 6 ± 5 h (SD), with a maximum of over 26 h. The seals spent more time hauled out at night (between 21:00 and 06:00 h) after the moult. The time spent hauled out and the haulout frequency declined from early summer to autumn. An individual seal had an average of 13 haulout sites, which were an average of 2.5 km apart. Approximately half of these haulout sites were located in the core 50% of the indi- vidual seals' home ranges. The high level of site fidelity emphasizes the need to identify suitable haulout areas and to develop measures for protecting the main resting sites of this endangered population. Additionally, guidelines for seal watching should be developed in order to mitigate the potential disturbance caused by increasing tourism on Lake Saimaa.
VOCAL COMMUNICATION AND INDIVIDUAL VARIATION IN BREEDING SOUTH AMERICAN SEA LIONS

The purpose of this study was to analyse the structure, social contexts, and individual variation of South American sea lion (Otaria flavescens) airborne vocal communication during the breeding season. This is the first comprehensive analysis of the vocal repertoire of this species. Since breeding colonies are complex acoustic environments, we expect that male, female, and pup vocalizations would show individuality, and that individual variation would rely on several acoustic traits. We identified four calls for adult males: high pitched call or HPC (aggressive interactions, such as attack and retreat displays, and fights), bark (aggressive interactions, territory establishment, and usually combined with growls), growl (male-female interactions), and exhalation (after agonistic encounters); and two for adult females: mother primary call or MPC (female-pup interactions, such as after birth, during pup separation, and pup development), and grunt (agonistic interactions between females). Juveniles vocalized yearling primary calls or YPC (searching for their mothers or after being threatened by females), pups gave pup primary calls or PPC (in response to MPCs, when hungry, searching for their mothers, if nursing was interrupted, or when trying to nurse). Our results suggest that male's HPC and bark, female's MPC, and pup's PPC have acoustic features that support individuality. These calls are associated with contexts in which recognition of neighbours (HPC and bark) or relatives (MPC and PPC) may confer a relative advantage in reproductive performance. Individual variation depended on frequency, temporal, and intensity traits; such multi-trait individuality could be regarded as an adaptation to colonial life to overcome the high noise levels within pinniped breeding colonies.
Becoming a teacher : tracing changes in pre-service English as a foreign language teachers' sense of efficacy

This longitudinal study aimed to trace changes in Turkish pre-service English as a foreign language teachers’ self-efficacy over a year, and to detect possible sources of information influencing their efficacy. Utilizing concurrent mixed model design of Creswell (2003) both qualitative and quantitative data was collected. A total of 40 pre-service teachers participated in the study. Findings indicated that pre-service English language teachers’ efficacy changed significantly over time. We also found that pre-service teachers seem to depend more on enactive mastery experience and social persuasion than on vicarious experience and affective state as sources of information. Based on our findings, measures are suggested on how to support pre-service teachers to improve their sense of efficacy. Implications for research on teaching and teacher education are discussed. Keywords : pre-service teachers; school observation; sources of teacher efficacy; student teaching; teachers’ sense of efficacy
Nonuniform Wavelet Packets on Local Fields of Positive Characteristic

Abstract The concept of nonuniform multiresolution analysis on local field of positive characteristic was considered by Shah and Abdullah for which the translation set is a discrete set which is not a group. We construct the associated wavelet packets for such an MRA and investigate their properties by means of the Fourier transform.
Predicting the stellar and non-equilibrium dust emission spectra of high-resolution simulated galaxies with DART-RAY

We describe the calculation of the stochastically heated dust emission using the 3D ray-tracing dust radiative transfer code dart-ray, which is designed to solve the dust radiative transfer problem for galaxies with arbitrary geometries. In order to reduce the time required to derive the non-equilibrium dust emission spectra from each volume element within a model, we implemented an adaptive spectral energy distribution library approach, which we tested for the case of axisymmetric galaxy geometries. To show the capabilities of the code, we applied dart-ray to a high-resolution N-body+SPH galaxy simulation to predict the appearance of the simulated galaxy at a set of wavelengths from the UV to the sub-mm. We analyse the results to determine the effect of dust on the observed radial and vertical profiles of the stellar emission as well as on the attenuation and scattering of light from the constituent stellar populations. We also quantify the proportion of dust re-radiated stellar light powered by young and old stellar populations, both bolometrically and as a function of infrared wavelength.
Artificial Neural Networks to Predict the Power Output of a PV Panel

The paper illustrates an adaptive approach based on different topologies of artificial neural networks (ANNs) for the power energy output forecasting of photovoltaic (PV) modules. The analysis of the PV module’s power output needed detailed local climate data, which was collected by a dedicated weather monitoring system. The Department of Energy, Information Engineering, and Mathematical Models of the University of Palermo (Italy) has built up a weather monitoring system that worked together with a data acquisition system. The power output forecast is obtained using three different types of ANNs: a one hidden layer Multilayer perceptron (MLP), a recursive neural network (RNN), and a gamma memory (GM) trained with the back propagation. In order to investigate the influence of climate variability on the electricity production, the ANNs were trained using weather data (air temperature, solar irradiance, and wind speed) along with historical power output data available for the two test modules. The model validation was performed by comparing model predictions with power output data that were not used for the network's training. The results obtained bear out the suitability of the adopted methodology for the short-term power output forecasting problem and identified the best topology.