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We study almost symmetric numerical semigroups and semigroup rings. We describe a characteristic property of the minimal free resolution of the semigroup ring of an almost symmetric numerical semigroup. For almost symmetric semigroups generated by four elements we will give a structure theorem by using the "row-factorization matrices", introduced by Moscariello. As a result, we give a simpler proof of Komeda's structure theorem of pseudo-symmetric numerical semigroups generated by four elements. Row-factorization matrices are also used to study shifted families of numerical semigroups. [ABSTRACT FROM AUTHOR]

Background: Atherosclerosis leading to cardiovascular disease (CVD) is the main cause of mortality and morbidity in patients with rheumatoid arthritis (RA). Paraoxonase1 (PON1) is the best understood member of plasma paraoxonases with anti-atherogenic properties. Patients and methods: Spanish RA (n = 549) consecutively recruited from 1 single center and 477 ethnically matched healthy controls were included in a case-control study. The concentration of PON1 was evaluated by means of an enzyme-linked immunosorbent sssay (ELISA). An arylesterase/paraoxonase assay kit was used to evaluate PON1 activity. Sample genotyping was performed by using TaqMan assays-on-demand. All results were expressed as medians ± interquartile range. One-way ANOVA comparisons were done using a nonparametric Kruskall-Wallis test. P values under 0.05 were considered to be significant. Results: The concentration of PON1 in the RA group was higher than in control group (p = 0.0003), although the differences were not significant when PON1 activities were compared between both groups. No significant differences were found related to distributions of rs662 genotypes in RA patients compared to healthy controls. Among rs854860 polymorphisms, overall genotype was widely distributed between RA patients and controls. Overall PON1 concentration in plasma was not significantly different between individuals carrying any of rs662 (p = 0.8501) or rs854860 (p = 0.2741) polymorphisms. Although PON1 levels were not associated with any of the SNPs in the study, differences appear when enzyme activities are compared for each SNP separately. CVD in RA patients correlate with increased PON1 levels and lower PON1 activity. Conclusions: Although protective role of PON1 against oxidative damage in vivo could be related to other activities, in our study arylesterase activity was useful to identify phenotypic differences with emphasis placed on two SNPs coding for nonconservative amino acid changes in the functional protein. [ABSTRACT FROM AUTHOR]

Numerical monoids (cofinite, additive submonoids of the non-negative integers) arise frequently in additive combinatorics, and have recently been studied in the context of factorization theory. Arithmetical numerical monoids, which are minimally generated by arithmetic sequences, are particularly well-behaved, admitting closed forms for many invariants that are difficult to compute in the general case. In this paper, we answer the question "when does omitting generators from an arithmetical numerical monoid S preserve its (well-understood) set of length sets and/or Frobenius number?" in two extremal cases: (1) we characterize which individual generators can be omitted from S without changing the set of length sets or Frobenius number; and (2) we prove that under certain conditions, nearly every generator of S can be omitted without changing its set of length sets or Frobenius number. [ABSTRACT FROM AUTHOR]

Let S⊆N be a numerical semigroup with multiplicity m, conductor c and minimal generating set P. Let L=S∩[0,c-1] and W(S)=|P||L|-c. In 1978, Herbert Wilf asked whether W(S)≥0 always holds, a question known as Wilf's conjecture and open since then. A related number W0(S), satisfying W0(S)≤W(S), has recently been introduced. We say that S is a near-miss in Wilf's conjecture if W0(S)<0. Near-misses are very rare. Here we construct infinite families of them, with c=4m and W0(S) arbitrarily small, and we show that the members of these families still satisfy Wilf's conjecture. [ABSTRACT FROM AUTHOR]

This paper is focused on numerical semigroups and presents a simple construction, that we call "dilatation", which, from a starting semigroup S, permits to get an infinite family of semigroups which share several properties with S. The invariants of each semigroup T of this family are given in terms of the corresponding invariants of S and both the Apéry set and the minimal generators of T are described. We also study three properties that are close to the Gorenstein property of the associated semigroup ring: almost Gorenstein, 2-AGL, and nearly Gorenstein properties. More precisely, we prove that S satisfies one of these properties if and only if each dilatation of S satisfies the corresponding one. [ABSTRACT FROM AUTHOR]

The preservation of decorated caves is a great challenge that has been reinforced by the microbial crisis occurring at emblematic sites such as the Lascaux and Altamira caves. To date, little is known about the microbial behavior of caves. One difficulty is that the term "cave" covers a wide variety of sites and structures. Past studies concentrated on caves with microbial disorders and were generally carried out in a time frame that was too short to gain an adequate picture of healthy microbial behaviors, the sine qua non of detecting potential imbalance. The aim of this study was to determine whether models of aerobiological behavior could be identified in several decorated caves. We monitored aerial rates of fungi and bacteria in five decorated caves of the Gard department (France) for periods of 2 years or more. A model behavior was identified in each cave. These models were cave dependent and were also season dependent in some caves. Following our fungal results, we suggest separating the caves into two groups. The caves which were strongly affected by the external environment throughout their entire length are the "non-self-purifying caves". The caves which were only affected by external environment at the entrance are the "self-purifying caves". [ABSTRACT FROM AUTHOR]

Atmospheric electricity has been studied since the early 1700s. This special issue unites new research that links atmospheric electricity with biology and human well-being that collectively highlight the importance of a rejuvenated interest in this field. The contributions show how atmospheric electricity can govern human well-being as well as a wide array of organisms and the processes they sustain and therefore serve as an appraisal to consider atmospheric electricity as a significant direct and indirect driver of biology. [Extracted from the article]

Air microbial pollution in touristic areas poses a risk for both the integrity of an ecosystem and human health. Microbiological monitoring together with environmental parameters monitoring allows for the assessment of the impacts and formulation of sound management decisions to protect humans and ecosystems. Four show caves from the Carpathian Mountains were selected for our study. The caves were sampled monthly to obtain an overview of the changes that occur over a yearly cycle. For the microbial monitoring, we used RIDA®COUNT test plates, while the environmental parameters were monitored with a variety of devices. Second and third generations of microbes extracted from the plates were grown on specific media for the purpose of 16S rRNA and 18S rRNA extraction and taxa identification. The bacterial communities identified in the air samples in the four investigated show caves were dominated by Staphylococcus, while regarding the fungi communities, Penicillium was more likely to occur in the touristic part of the caves and Cladosporium in the non-visited passages. Together with data on number of visitors, number of bats and radon levels we were able understand the impact of tourists on the cave environment and to generate microbiological risk maps for human health. This type of comprehensive study can be used not only to protect the integrity of a touristic area from the impacts caused by the introduction of allochthonous organic matter, but also for the protection of the tourists and guides from potential pathogenic taxa. [ABSTRACT FROM AUTHOR]

We describe the second (generalized) Feng-Rao distance for elements in an Arf numerical semigroup that are greater than or equal to the conductor of the semigroup. This provides a lower bound for the second Hamming weight for one point AG codes. In particular, we can obtain the second Feng-Rao distance for the codes defined by asymptotically good towers of function fields whose Weierstrass semigroups are inductive. In addition, we compute the second Feng-Rao number, and provide some examples and comparisons with previous results on this topic. These calculations rely on Apéry sets, and thus several results concerning Apéry sets of Arf semigroups are presented. [ABSTRACT FROM AUTHOR]

The common behaviour of many families of numerical semigroups led to defining, firstly, the Frobenius varieties and, secondly, the (Frobenius) pseudo-varieties. However, some interesting families are still not covered by these definitions. To overcome this situation, here we introduce the concept of Frobenius restricted variety (or R-variety). We generalize most of the results for varieties and pseudo-varieties to R-varieties. In particular, we study the tree structure that arises within them. [ABSTRACT FROM AUTHOR]

We introduce the concept of homogeneous numerical semigroups and show that all homogeneous numerical semigroups with Cohen-Macaulay tangent cones are of homogeneous type. In embedding dimension three, we classify all numerical semigroups of homogeneous type into numerical semigroups with complete intersection tangent cones and the homogeneous ones which are not symmetric with Cohen-Macaulay tangent cones. We also study the behavior of the homogeneous property by gluing and shiftings to construct large families of homogeneous numerical semigroups with Cohen-Macaulay tangent cones. In particular we show that these properties fulfill asymptotically in the shifting classes. Several explicit examples are provided along the paper to illustrate the property. [ABSTRACT FROM AUTHOR]

In this manuscript we show that the second Feng-Rao number of any telescopic numerical semigroup agrees with the multiplicity of the semigroup. To achieve this result we first study the behavior of Apéry sets under gluings of numerical semigroups. These results provide a bound for the second Hamming weight of one-point Algebraic Geometry codes, which improves upon other estimates such as the Griesmer Order Bound. [ABSTRACT FROM AUTHOR]

Effects of chitosan combined with nisin on quality enhancement in jumbo squid (Dosidicus gigas) were investigated during cold storage (4 ± 1 °C). 1% chitosan combined with different concentrations of nisin (0, 2 and 6 g/L) were utilized as preservatives. Changes in human sensory evaluation, GC–MS, total variable counts, and physiochemical indexes, including weight loss, colour, total volatile basic nitrogen and K value, were synchronously measured. Results demonstrated that 1% chitosan combined with 6 g/L nisin maintained high sensory scores, low moisture loss and volatile spoilage products. The optimized method also inhibited microbial propagation, nutrient (protein, nucleotides, etc) degradation, etc. This method is promising in aquatic products quality preservation. [ABSTRACT FROM AUTHOR]

We report on the determination of the spore concentration and the species composition of the airborne fungi in selected caves of the Tatra Mountains, Poland. The following caves were surveyed: Mylna, Obłazkowa, Mroźna, Zimna and Naciekowa. The sampling was carried out in July 2015 and in January 2016. The aeromycological analyses were performed with the impact method, using the Air Ideal 3P apparatus and potato dextrose agar (PDA, Biocorp) culture medium. In the course of the July 2015 analysis, 17 species of fungi were isolated and 11 species were isolated in January 2016. In Mylna and Naciekowa caves, the dominant species were Cladosporium cladosporioides and Stachybotrys cylindrospora. In Obłazkowa cave, Rhizoctonia predominated and in Zimna cave—the colonies of the yeast-like fungi, along with S. cylindrospora. In Mroźna cave, Penicillium notatum was the most abundant taxon. In the winter time, in the majority of the caves Penicillium spp. predominated, with the exception of Mroźna and Naciekowa caves where Aspergillus niger was dominant. We propose that aeromycological monitoring be performed regularly in the following caves: Mroźna, Naciekowa and Zimna. [ABSTRACT FROM AUTHOR]

We propose an efficient solution method based on a decomposition of set-partitioning formulation of an integrated surgery planning and scheduling problem with chance constraints. The studied problem is characterized by a set of identical operating rooms (ORs), a set of surgeries with uncertain durations, a set of surgeons, and surgery dependent turnover times. The decision variables include the number of ORs to open, assignments of surgeries and surgeons to ORs in admissible periods, and the sequence of surgeries to be performed in a period. The objective is to minimize the cost of opening ORs and the penalties associated with turnover times.In the proposed formulation, the column generation subproblem is decomposed over ORs and time periods. The structure of the subproblem is further exploited and transformed to a shortest path problem. A search algorithm has been devised to efficiently solve the resulting subproblem, subject to some optimality and feasibility conditions. The proposed computational method outperforms the standard chance constrained model and reduces the solution time significantly. Furthermore, extensive simulation experiments have been carried out to compare the performance of three variants of the underlying formulations and evaluate the sensitivity of the decisions to the probability of exceeding a session length. [ABSTRACT FROM AUTHOR]

To a numerical semigroup S, Eliahou associated a number E(S) and proved that numerical semigroups for which the associated number is non negative satisfy Wilf’s conjecture. The search for counterexamples for the conjecture of Wilf is therefore reduced to semigroups which have an associated negative Eliahou number. Eliahou mentioned 5 numerical semigroups whose Eliahou number is -1. The examples were discovered by Fromentin who observed that these are the only ones with negative Eliahou number among the over 1013 numerical semigroups of genus up to 60. We prove here that for any integer n there are infinitely many numerical semigroups S such that E(S)=n, by explicitly giving families of such semigroups. We prove that all the semigroups in these families satisfy Wilf’s conjecture, thus providing not previously known examples of semigroups for which the conjecture holds. [ABSTRACT FROM AUTHOR]

B cell leukaemia is one of the most frequent malignancies in the paediatric population, but also affects a significant proportion of adults in developed countries. The majority of infant and paediatric cases initiate the process of leukaemogenesis during foetal development (in utero) through the formation of a chromosomal translocation or the acquisition/deletion of genetic material (hyperdiploidy or hypodiploidy, respectively). This first genetic insult is the major determinant for the prognosis and therapeutic outcome of patients. B cell leukaemia in adults displays similar molecular features as its paediatric counterpart. However, since this disease is highly represented in the infant and paediatric population, this review will focus on this demographic group and summarise the biological, clinical and epidemiological knowledge on B cell acute lymphoblastic leukaemia of four well characterised subtypes: t(4;11) MLL-AF4, t(12;21) ETV6-RUNX1, t(1;19) E2A-PBX1 and t(9;22) BCR-ABL1. [ABSTRACT FROM AUTHOR]

We derive a set of polynomial and quasipolynomial identities for degrees of syzygies in the Hilbert series of numerical semigroup $$\langle d_1,\ldots ,d_m\rangle $$ , $$m\ge 2$$ , generated by an arbitrary set of positive integers $$\left\{ d_1, \ldots ,d_m\right\} $$ , $$\gcd (d_1,\ldots ,d_m)=1$$ . These identities are obtained by studying the rational representation of the Hilbert series and the quasipolynomial representation of the Sylvester waves in the restricted partition function. In the cases of symmetric semigroups and complete intersections, these identities become more compact; for the latter we find a simple identity relating the degrees of syzygies with elements of generating set $$\left\{ d_1,\ldots ,d_m\right\} $$ and give a new lower bound for the Frobenius number. [ABSTRACT FROM AUTHOR]

Alternaria species, including A. solani and A. alternata, are a serious threat to potato cultivation and cause necrotic leaf spots, leading to premature defoliation and yield losses. To reduce the impact of the disease, a timely prediction of a disease outbreak is important. Worldwide, modelling attempts have been made to predict the occurrence of Alternaria in order to take adequate measures. In the present paper, we made an effort to classify the existing prediction models and subdivided them into three categories: plant-based, pathogen-based and plant-pathogen-based models. Plant-based models predict the susceptibility of the host crop and presume that Alternaria inoculum is abundantly present and not the restrictive factor, whereas pathogen-based models consider one or more stages of the Alternaria life cycle and suppose that the host crop is always susceptible. The plant-pathogen-based models try to take into account the complete plant-pathogen-environment relationship. In this paper, a critical review of the described models for Alternaria leaf spot is presented. To illustrate the discrepancy between the predicted and the observed dates of the first Alternaria symptoms or the discrepancy between the suggested first treatment and necessity to treat Alternaria, the existing models were subjected to the Belgian weather conditions. It turns out that these models are not applicable in Belgium or similar regions. This can be partially attributed to the fact that most of the currently available models are too simplistic (only plant- or pathogen-based) for regions where the disease pressure highly fluctuates between growing seasons and between locations within one season. Finally, perspectives for model improvement are given taking into account both plant, pathogen and environment. [ABSTRACT FROM AUTHOR]

Since the 1950s, research has been undertaken to promote algal oil as a sustainable alternative to fossil fuels. This paper statistically analyzed 317 studies of algal bioreactors to determine the interdependence of biological and physical factors affecting oil yield. Algal growth rates in bioreactors often (71 %) exceeded maximal growth rates cited in the literature, and biomass was generally higher than maximum values cited for laboratory cultures. Growth rate decreased with increasing biomass, and biomass, not growth, dominated production rate, which was higher in closed than in open bioreactors. Except for Chlorella cultured in horizontal tubular reactors, there were no statistical differences in algal production when grown in different types of reactors. Production decreased with increasing bioreactor volume, but increased with surface to volume ratio of the bioreactor. In contrast, estimated oil yields increased with bioreactor volume. Four groups of bioreactors were identified based on their oil yields and biomass production: (1) higher yields with lower production were limited to open systems with volumes ≥10 L; (2) higher yields with higher production were almost exclusively closed bioreactors from 10 to 10 L; (3) lower yields with higher production were closed systems from 3 to 99 L; and (4) lower yields with lower production were a mix of open and closed systems with diverse volumes. Based on these groups, it is suggested that intermediate volume bioreactors with higher surface to volume ratios could give higher yields and production rates and would avoid the environmental and scale-up problems inherent in large bioreactors currently being used commercially to culture microalgae. [ABSTRACT FROM AUTHOR]

Background: Bone marrow mesenchymal stromal cells (BM-MSCs) are an essential cell type in the hematopoietic microenvironment. The question of whether MSCs from patients with different leukemias have cytogenetic abnormalities is controversial. In this study, we attempted to review the cytogenetic profiles of MSCs in patients with leukemia, and verify whether these profiles were related to different ex vivo culture conditions or to chronic or acute disease states. This information could be useful in clarifying the origin of MSCs and developing clinical applications for this cell type. Methods: A systematic literature search was performed using the PubMed search engine. Studies published over the past 15 years, i.e., between 1995 and January 2015, were considered for review. The following keywords were used: 'cytogenetic,' 'leukemia,' 'bone marrow,' and 'mesenchymal stromal cells.' Results: Some studies demonstrated that BM-MSCs are cytogenetically normal, whereas others provided evidence of aberrations in these cells Conclusions: Studying cytogenetic changes of MSCs in a variety of leukemias will help researchers understand the nature of these tumors and ensure the safety of human stem cells in clinical applications. [ABSTRACT FROM AUTHOR]

This article introduces patterns of ideals of numerical semigroups, thereby unifying previous definitions of patterns of numerical semigroups. Several results of general interest are proved. More precisely, this article presents results on the structure of the image of patterns of ideals, and also on the structure of the sets of patterns admitted by a given ideal. [ABSTRACT FROM AUTHOR]

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Given positive integers $$n_1,\ldots ,n_p$$ , we say that a submonoid M of $$({\mathbb N},+)$$ is a $$(n_1,\ldots ,n_p)$$ -bracelet if $$a+b+\left\{ n_1,\ldots ,n_p\right\} \subseteq M$$ for every $$a,b\in M\backslash \left\{ 0\right\} $$ . In this note, we explicitly describe the smallest $$\left( n_1,\ldots ,n_p\right) $$ -bracelet that contains a finite subset X of $${\mathbb N}$$ . We also present a recursive method that enables us to construct the whole set $$\mathcal B(n_1,\ldots ,n_p)=\left\{ M|M \quad \text {is a} \quad (n_1,\ldots ,n_p)\text {-bracelet}\right\} $$ . Finally, we study $$(n_1,\ldots ,n_p)$$ -bracelets that cannot be expressed as the intersection of $$(n_1,\ldots , n_p)$$ -bracelets properly containing it. [ABSTRACT FROM AUTHOR]

Currently, stochastic optimization on the one hand and multi-objective optimization on the other hand are rich and well-established special fields of Operations Research. Much less developed, however, is their intersection: the analysis of decision problems involving multiple objectives and stochastically represented uncertainty simultaneously. This is amazing, since in economic and managerial applications, the features of multiple decision criteria and uncertainty are very frequently co-occurring. Part of the existing quantitative approaches to deal with problems of this class apply scalarization techniques in order to reduce a given stochastic multi-objective problem to a stochastic single-objective one. The present article gives an overview over a second strand of the recent literature, namely methods that preserve the multi-objective nature of the problem during the computational analysis. We survey publications assuming a risk-neutral decision maker, but also articles addressing the situation where the decision maker is risk-averse. In the second case, modern risk measures play a prominent role, and generalizations of stochastic orders from the univariate to the multivariate case have recently turned out as a promising methodological tool. Modeling questions as well as issues of computational solution are discussed. [ABSTRACT FROM AUTHOR]

Research on the distribution and structure of fungal communities in caves is lacking. Kartchner Caverns is a wet and mineralogically diverse carbonate cave located in an escarpment of Mississippian Escabrosa limestone in the Whetstone Mountains, Arizona, USA. Fungal diversity from speleothem and rock wall surfaces was examined with 454 FLX Titanium sequencing technology using the Internal Transcribed Spacer 1 as a fungal barcode marker. Fungal diversity was estimated and compared between speleothem and rock wall surfaces, and its variation with distance from the natural entrance of the cave was quantified. Effects of environmental factors and nutrient concentrations in speleothem drip water at different sample sites on fungal diversity were also examined. Sequencing revealed 2,219 fungal operational taxonomic units (OTUs) at the 95 % similarity level. Speleothems supported a higher fungal richness and diversity than rock walls. However, community membership and the taxonomic distribution of fungal OTUs at the class level did not differ significantly between speleothems and rock walls. Both OTU richness and diversity decreased significantly with increasing distance from the natural cave entrance. Community membership and taxonomic distribution of fungal OTUs also differed significantly between the sampling sites closest to the entrance and those furthest away. There was no significant effect of temperature, CO concentration, or drip water nutrient concentration on fungal community structure on either speleothems or rock walls. Together, these results suggest that proximity to the natural entrance is a critical factor in determining fungal community structure on mineral surfaces in Kartchner Caverns. [ABSTRACT FROM AUTHOR]

The aim of this experiment was to evaluate the effects of saline water irrigation in two citrus species, 'Clemenules' mandarin (CLM) and 'Star Ruby' grapefruit (SR), both grafted on 'Cleopatra' mandarin (a rootstock considered as a Cl excluder, but a Na non-excluder). The experiment was carried out over 3 years (2008-2010) in the IMIDA experimental orchard located at Torre Pacheco (Murcia), using 15-year-old trees irrigated with water of two salinity levels: 0 and 40 mM NaCl. Our data indicate different physiological and agronomic responses of the two citrus species (CLM and SR). The higher salt tolerance observed in CLM was due to the lower accumulation of Cl in leaves and the greater reduction in vegetative growth with no effect on the quantity or quality of yield. Further, the quality of yield was improved due to the increase in total soluble solids and acidity, since the quality of the juice of CLM fruits is negatively affected in semi-arid regions by lower acidity levels. However, in SR, a high leaf Cl concentration reduced both vegetative growth and yield and affected fruit quality negatively by increasing the titratable acidity. The increase in the acidity in SR fruits due to salinity translated into a delay of the ripening process, since more time was required to reach optimal levels for the fresh market. Thus, based on these results, we recommend the use of salt-tolerant species such as 'Clemenules' mandarin grafted on 'Cleopatra' mandarin for semi-arid regions, where the only irrigation water available is saline. [ABSTRACT FROM AUTHOR]

Alternaria is frequently found as airborne fungal spores and is recognized as an important cause of respiratory allergies. The aerobiological monitoring of fungal spores was performed using a Burkard volumetric spore traps. To establish predicting variables for daily and weakly spore counts, a stepwise multiple regression between spore concentrations and independent variables (meteorological parameters and lagged values from the series of spore concentrations: previous day or week concentration (Alt) and mean concentration of the same day or week in other years ( C)) was made with data obtained during 2009-2011. Alternaria conidia are present throughout the year in the atmosphere of Tetouan, although they show important seasonal fluctuations. The highest levels of Alternaria spores were recorded during the spring and summer or autumn. Alternaria showed maximum daily values in April, May or October depending on year. When the spore variables of Alternaria, namely C and Alt, and meteorological parameters were included in the equation, the resulting R satisfactorily predict future concentrations for 55.5 to 81.6 % during the main spore season and the pre-peak 2. In the predictive model using weekly values, the adjusted R varied from 0.655 to 0.676. The Wilcoxon test was used to compare the results from the expected values and the pre-peak spore data or weekly values for 2012, indicating that there were no significant differences between series compared. This test showed the C, Alt, frequency of the wind third quadrant, maximum wind speed and minimum relative humidity as the most efficient independent variables to forecast the overall trend of this spore in the air. [ABSTRACT FROM AUTHOR]

The common behavior of several families of numerical semigroups led up to defining the Frobenius varieties. However, some interesting families were out of this definition. In order to overcome this situation, in this paper, we introduce the concept of (Frobenius) pseudo-varieties. Moreover, we will show that most of the results for varieties can be generalized to pseudo-varieties. [ABSTRACT FROM AUTHOR]

An aerobiological survey was conducted through five consecutive years (2006-2010) at Worcester (England). The concentration of 20 allergenic fungal spore types was measured using a 7-day volumetric spore trap. The relationship between investigated fungal spore genera and selected meteorological parameters (maximum, minimum, mean and dew point temperatures, rainfall, relative humidity, air pressure, wind direction) was examined using an ordination method (redundancy analysis) to determine which environmental factors favoured their most abundance in the air and whether it would be possible to detect similarities between different genera in their distribution pattern. Redundancy analysis provided additional information about the biology of the studied fungi through the results of the Spearman's rank correlation. Application of the variance inflation factor in canonical correspondence analysis indicated which explanatory variables were auto-correlated and needed to be excluded from further analyses. Obtained information will be consequently implemented in the selection of factors that will be a foundation for forecasting models for allergenic fungal spores in the future. [ABSTRACT FROM AUTHOR]

The analysis of the literature data reveals that, as a rule, layered double hydroxides prepared by co-precipitation have an imperfect structure; however, there are different viewpoints on the type of the defects. Thermal decomposition of Mg-Al, Mg-Ga, and Ni-Al hydroxides occurs through dehydration, dehydroxylation, and decarbonization. The first stage affords a layered dehydrated phase with a strongly disordered structure, which is a subject of controversy. Also, the question on the diffusion of cations during thermolysis is still open, i.e., whether the Mg-Al, Mg-Ga and Ni-Al systems degrade with the development of a nanoheterogenous oxide systems or a single-phase mixed oxide, but with very defective structure, is formed. [ABSTRACT FROM AUTHOR]

The Huneke-Wiegand conjecture has prompted much recent research in Commutative Algebra. In studying this conjecture for certain classes of rings, García-Sánchez and Leamer construct a monoid $S_{\varGamma}^{s}$ whose elements correspond to arithmetic sequences in a numerical monoid Γ of step size s. These monoids, which we call Leamer monoids, possess a very interesting factorization theory that is significantly different from the numerical monoids from which they are derived. In this paper, we offer much of the foundational theory of Leamer monoids, including an analysis of their atomic structure, and investigate certain factorization invariants. Furthermore, when $S_{\varGamma}^{s}$ is an arithmetical Leamer monoid, we give an exact description of its atoms and use this to provide explicit formulae for its Delta set and catenary degree. [ABSTRACT FROM AUTHOR]

From the viewpoint of fracture mechanics, of importance is the near-tip field which can be characterized as field intensity factors. In this paper, the crack-tip field intensity factors of the stress and electric displacement in two dimensional piezoelectric solids are evaluated by using four approaches including the displacement extrapolation, the stress method, the J-integral and the modified crack closure integral method (MCCI) based on a boundary element method (BEM). The strongly singular displacement boundary integral equations (BIEs) are applied on the external boundary of the cracked solid, while the hypersingular traction BIEs are used on the crack faces. Three numerical examples are presented to show the path independence and the high accuracy of the J-integral in piezoelectric materials and to analyze the pros and cons of these approaches in evaluating the field intensity factors. [ABSTRACT FROM AUTHOR]

In this paper we present an algorithm for computing the set of saturated numerical semigroups of a given genus. We see how the set of saturated numerical semigroups can be arranged in a tree rooted in $\mathbb{N}$ and we describe the sons of any vertex of this tree. [ABSTRACT FROM AUTHOR]

We study arithmetic properties of tangent cones associated to large families of monomial curves obtained by gluing. In particular, we characterize their Cohen-Macaulay and Gorenstein properties and prove that they have non-decreasing Hilbert functions. The results come from a careful analysis of some special Apéry sets of the numerical semigroups obtained by gluing under a condition that we call specific gluing. As a consequence, we complete and extend the results proved by Arslan et al. (in Proc. Am. Math. Soc. 137:2225-2232, ) about nice gluings by using different techniques. Our results also allow to prove that for a given numerical semigroup with a non-decreasing Hilbert function and an integer q>1, all extensions of it by q, except a finite number, have non-decreasing Hibert functions. [ABSTRACT FROM AUTHOR]

We prove that the numerical semigroups associated to the combinatorial configurations satisfy a family of linear, non-homogeneous, symmetric patterns. We use these patterns to prove an upper bound of the conductor and we also give an upper bound of the multiplicity. Also, we compare bounds of the conductor of numerical semigroups associated to balanced configurations, and to configurations with coprime parameters. The proof of the latter involves a bound of the conductor of prime power generated numerical semigroups. [ABSTRACT FROM AUTHOR]

Altamira Cave (north of Spain) contains one of the world's most prominent Paleolithic rock art paintings, which are threatened by a massive microbial colonization of ceiling and walls. Previous studies revealed that exchange rates between the cave and the external atmosphere through the entrance door play a decisive role in the entry and transport of microorganisms (bacteria and fungi) and nutrients to the interior of the cave. A spatial-distributed sampling and measurement of carrier (CO) and trace (CH) gases and isotopic signal of CO (δC) inside the cave supports the existence of a second connection (active gas exchange processes) with the external atmosphere at or near the Well Hall, the innermost and deepest area of the cave. A parallel aerobiological study also showed that, in addition to the entrance door, there is another connection with the external atmosphere, which favors the transport and increases microorganism concentrations in the Well Hall. This double approach provides a more complete knowledge on cave ventilation and revealed the existence of unknown passageways in the cave, a fact that should be taken into account in future cave management. [ABSTRACT FROM AUTHOR]

This research aims to analyse the drivers to company innovation and their effects on the financial performance. This study is based upon a sample of companies, located in two neighbouring countries (Portugal and Spain). Linear regression was the methodology deployed to analyse the importance of innovation types (differences between Portugal and Spain). To analyse the extent to which the innovation capacity variables influence financial performance (turnover), we made recourse to Probit Regression models. Our results show significant differences in terms of both the drivers and inhibitors to innovation in these two countries. The introduction of products into new markets only proved significant at Spanish companies whilst innovations in both products and processes are significant in both sets of Iberian companies. [ABSTRACT FROM AUTHOR]

Given the crucial role of entrepreneurial foreign activity as a source of corporate profits and competitive advantage, it is of interest to investigate which factors may help promote it. This paper evaluates whether entrepreneurial foreign activities of small and medium-sized multinational enterprises (SMNEs) of Latin American developing countries are affected by international certifications, corporate social responsibility and green management. To that aim, we use a sample of 100 Peruvian exporting firms from several sectors and a methodology consisting of partial least squares structural equation modeling. Results reveal that, while acquiring and holding international certifications as well as the investments carried out in actions related to corporate social responsibility do not have positive effects on the performance of entrepreneurial foreign activities of Peruvian SMNEs, green management exerts a positive influence. Therefore, environmental management is revealed as an effective tool to help firms from developing countries compete successfully in the markets and, in turn, improve the economic situation in those regions. [ABSTRACT FROM AUTHOR]

This research analyzes the influence of a global mindset on the internationalization behavior of Norwegian and Portuguese small firms. It specifically sets out to assess the role of global orientation of the entrepreneur and firm perspectives on the global market. Based on a sample of 354 small firms, we used structural equation modeling to conduct our analysis. The results show the differing importance of a range of factors in explaining global mindset in different contexts. The global mindset of Norwegian entrepreneurs conditions their behavior and international experience, while for Portuguese entrepreneurs it affects the cognitive domain and their technical expertise. Global mindset and global orientation have more relevant effects on the internationalization behavior of Norwegian firms than that of Portuguese firms. [ABSTRACT FROM AUTHOR]

If social enterprises are to be competitive in the marketplace, they must use Strategic Management tools to improve efficiency, while maintaining their effectiveness levels. They can achieve this goal by introducing new management methods that make use of innovation. The aim of the current study was to analyze the effect of the use of management tools in social enterprises, referred to here as Social Management, on the effectiveness and efficiency levels of these enterprises. From a sample of 129 work integration social enterprises (WISEs), this study shows the existence of a statistically significant relationship between the application of Strategic Management tools, more commonly found in for-profit organizations, and the effectiveness and efficiency of WISEs in the social economy. The influence of the use of these tools was found to be positive in the case of social effectiveness (improving the employment rate) but negative in the case of economic effectiveness (profitability). [ABSTRACT FROM AUTHOR]

Delorme suggested that the set of all complete intersection numerical semigroups can be computed recursively. We have implemented this algorithm, and particularized it to several subfamilies of this class of numerical semigroups: free and telescopic numerical semigroups, and numerical semigroups associated to an irreducible plane curve singularity. The recursive nature of this procedure allows us to give bounds for the embedding dimension and for the minimal generators of a semigroup in any of these families. [ABSTRACT FROM AUTHOR]

Rheological profile studies for apple pomace ultrafiltration sludge (APS) broth with filamentous fungus, Aspergillus niger NRRL-567 during citric acid (CA) fermentation are reported for the biomass developed in a 7.5 l bench scale fermentor. CA bioproduction of 23.67 ± 1.0 g/l APS and 40.34 ± 1.98 g/l APS was obtained in control (120 h) and in treatment with inducer, MeOH 3% ( v/v), respectively, after 132 h of fermentation by A. niger NRRL 567. The rheological properties of the fermentation broth including pellets were analyzed. The control demonstrated non-Newtonian pseudoplastic behaviour due to more filamentous growth. However, in treatment supplemented with inducer (methanol), pellet form was observed during fermentation with less viscous non-Newtonian broths. The power law model was followed with good confidence of fit (77.8-88.9%) throughout the fermentation in treatment with MeOH as an inducer. However, power law was followed with moderate fit of confidence (65.3-75.9%) at the beginning of fermentation until 48 h and later followed a good confidence of fit (75.9-88.2%) until 144 h of fermentation in control. Important rheological changes occurred in the broth during maximal CA production phase along with increase in biomass in the pelleted mycelium form. [ABSTRACT FROM AUTHOR]

In this paper, we use the Apéry table of the numerical semigroup associated to an affine monomial curve in order to characterize arithmetic properties and invariants of its tangent cone. In particular, we precise the shape of the Apéry table of a numerical semigroup of embedding dimension 3, when the tangent cone of its monomial curve is Buchsbaum or 2-Buchsbaum, and give new proofs for two conjectures raised by Sapko (Commun. Algebra 29:4759-4773, ) and Shen (Commun. Algebra 39:1922-1940, ). We also provide a new simple proof in the case of monomial curves for Sally's conjecture (Numbers of Generators of Ideals in Local Rings, ) that the Hilbert function of a one-dimensional Cohen-Macaulay ring with embedding dimension three is non-decreasing. Finally, we obtain that monomial curves of embedding dimension 4 whose tangent cones are Buchsbaum, and also monomial curves of any embedding dimensions whose numerical semigroups are balanced, have non-decreasing Hilbert functions. Numerous examples are provided to illustrate the results, most of them computed by using the NumericalSgps package of GAP (Delgado et al., NumericalSgps-a GAP package, ). [ABSTRACT FROM AUTHOR]