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In this paper, we study the connection between the odd cycles of a finite, simple graph [Formula: see text] and the symbolic powers of its edge ideal. When the odd cycles of [Formula: see text] are disjoint, we give a decomposition of the symbolic powers of the edge ideal based on the number and size of the odd cycles of [Formula: see text]. This shows that the symbolic powers of the edge ideal are completely dependent on the odd cycles of [Formula: see text].

Dama gazelles (Nanger dama Pallas, 1766) are critically endangered within their native habitat of northern Africa’s Sahelo-Saharan Zone. However, several Texas ranches maintain populations that pro...

In 2019, a number of allergens (haptens), henceforth, "the audit allergens," were considered as potential additions to the European Baseline Series (EBS), namely, sodium metabisulfite, 2-bromo-2-nitropropane-1,3-diol, diazolidinyl urea, imidazolidinyl urea, Compositae mix II (2.5% or 5% pet), linalool hydroperoxides (lin-OOH), limonene hydroperoxides (lim-OOH), benzisothiazolinone (BIT), octylisothiazolinone (OIT), decyl glucoside, and lauryl glucoside; Evernia furfuracea (tree moss), was additionally tested by some departments as well.To collect further data on patch test reactivity and clinical relevance of the audit allergens in consecutive patients across Europe.Patch test data covering the audit allergens in 2019 and 2020 were collected by those departments of the European Surveillance System on Contact Allergies testing these, as well as further collaborators from the EBS working group of the European Society of Contact Dermatitis (ESCD), and the Spanish Grupo Español de Investigación en Dermatitis de Contacto y Alergia Cutánea. As patch test outcome, reactions between day (D) 3 and D5 were considered.Altogether n = 12 403 patients were tested with any of the audit allergen. Positive reactions were most common to lin-OOH 1% pet. (8.74% [95%CI: 8.14-9.37%]), followed by lin-OOH 0.5% pet., and lim-OOH 0.3% pet (5.41% [95% CI: 4.95-5.89%]). Beyond these terpene hydroperoxides, BIT 0.1% pet. was the second most common allergen with 4.72% (95% CI: 4.2-5.28%), followed by sodium metabisulfite 1% pet. (3.75% [95%CI: 3.32-4.23%]) and Compositae mix 5% pet. (2.31% [95% CI: 1.84-2.87%]). For some allergens, clinical relevance was frequently difficult to ascertain.Despite many positive patch test reactions, it remains controversial whether lin- and lim-OOH should be tested routinely, while at least the two preservatives BIT and sodium metabisulfite appear suitable. The present results are a basis for further discussion and ultimately decision on their implementation into routine testing among the ESCD members.

This paper is concerned with the question of whether geometric structures such as cell complexes can be used to simultaneously describe the minimal free resolutions of all powers of a monomial ideal. We provide a full answer in the case of square-free monomial ideals of projective dimension one, by introducing a combinatorial construction of a family of (cubical) cell complexes whose 1-skeletons are powers of a graph that supports the resolution of the ideal.

Let $I$ be a square-free monomial ideal $I$ of projective dimension one. Starting with the Taylor complex on the generators of $I^r$, we use Discrete Morse theory to describe a CW complex that supports a minimal free resolution of $I^r$. To do so, we concretely describe the acyclic matching on the faces of the Taylor complex., Comment: To appear in Journal of Algebraic Combinatorics

North American porcupines (Erethizon dorsatum) have expanded their range into central Texas and are now frequent users of caves as den sites. What remains unknown is how caves affect their home range, and their local habitat preferences. This information is important for management decisions on Joint Base San Antonio – Camp Bullis where novel and abundant porcupine scat in caves could jeopardize federally endangered cave-obligate arthropods by allowing for the invasion of less specialized terrestrial species. To better understand porcupine home range and habitat use at Camp Bullis, we trapped four porcupines at cave entrances and fitted them with GPS collars. The 95% home range averaged 71.3 ha for females and measured 420.6 ha for the male. The 50% core habitat averaged 55.4 ha for females and measured 7.4 ha for the male. Porcupines typically stayed near the den-cave trap site except when visiting more diverse mixed forest patches. At the landscape and point levels, individuals selected for forested cover and avoided open areas. At the home range level, individuals selected for bare ground and roads, which were likely used to get from the cave den site to feed at mixed forest patches. Typically solitary, individuals in this study tolerated sharing a cave. Because of the small sample size and single sampling location, this study represents a pilot study and additional research is needed to establish concrete conclusions. Should cave managers need to limit the cave use by porcupines, a cave gate, exclosure, or reduction of forested cover would make caves less desirable.

The multiple spatial and temporal parameters affecting cattle herd distribution and activity dynamics can significantly affect resource utilization but are not fully understood. The aim of this study was to determine whether current animal tracking technology and spatio-temporal analysis tools can be used to integrate multi-scale information on herd distribution patterns as a function of seasonal forage production, periods of the day, animal activity, and landscape features. Positional and activity information of 11 free-ranging cows within a 31-member herd was obtained at 5-min intervals by using GPS collars for 1 year within a 457-ha ranch in the semi-arid rangelands of South Texas. Forage biomass was calculated with satellite imagery. Spatial analysis of cattle distribution and landscape features was conducted with GIS.Herd spread was greatest during the growing season. Throughout the year, during midday, the herd showed smaller spread and greater use of shade patches than any other time of day. Cattle also aggregated under trees in winter, particularly during the night. There was no statistically significant overall pattern of seasonal changes in the use of water and supplemental feeding areas, but a trend toward highest use during the winter. However, significantly different diurnal patterns in the use of supplemental feed and water were observed within each season.This study found a strong influence of shade patches relative to the influence of water and supplemental feeding areas on the diurnal and seasonal movement patterns of cattle in shrub-dominated rangeland. Although this study used only 11 tracked cows in a 31-member herd, the results indicated that techniques such as seasonal and diurnal GPS tracking, GIS, and remote sensing data enable evaluation of multiple spatial and temporal dynamics of cattle distribution and activity patterns. The smaller spread during the dry winter season associated with the observed aggregation of individuals in water and supplemental feeding areas, may aid in determining the most critical times for providing supplemental resources and guide the allocation of those resources to areas not frequently used by cattle, thus stimulating the animals to visit unused sites during the non-growing season.

Let $I_X$ be the saturated homogeneous ideal defining a codimension two arithmetically Cohen-Macaulay scheme $X \subseteq \mathbb{P}^n$, and let $I_X^{(m)}$ denote its $m$-th symbolic power. We are interested in when $I_X^{(m)} = I_X^m$. We survey what is known about this problem when $X$ is locally a complete intersection, and in particular, we review the classification of when $I_X^{(m)} = I_X^m$ for all $m \geq 1$. We then discuss how one might weaken these hypotheses, but still obtain equality between the symbolic and ordinary powers. Finally, we show that this classification allows one to: (1) simplify known results about symbolic powers of ideals of points in $\mathbb{P}^1 \times \mathbb{P}^1$; (2) verify a conjecture of Guardo, Harbourne, and Van Tuyl, and (3) provide additional evidence to a conjecture of R\"omer., Comment: This project was started at the Mathematisches Forschungsinstitut Oberwolfach (MFO) as part of the mini-workshop "Ideals of Linear Subspaces, Their Symbolic Powers and Waring Problems" held in February 2015. Final version of paper; to appear in Communications in Algebra

Habitat selection information is important for both breeding on Texas ranches and repatriation in Africa. This is especially true for the critically endangered dama gazelle (Nanger dama). Exotic dama gazelles of the eastern subspecies (N. dama ruficollis) wearing GPS-radio collars were tracked for one year on two Texas ranches. Three adult and two subadult males were collared from a large (8,996 ha) pasture in west Texas. Next, collars went on all males plus all females released into a 202 ha Edwards Plateau pasture (seven adult females, one maturing male, and one to three adult males). On both sites, the gazelles favored the less steep terrain of the Ector soil series. Adult male core areas averaged 440 ha in west Texas (vegetation sparse) and 57 ha on the Edwards Plateau (dense food stands). These relationships allowed for estimation of the number of adult males that could be stocked in the larger pasture while still allowing room for the males to spread out. No special affinity for water sources was found, although dama gazelles do drink during hot weather when water is available. There was no consistent seasonal distributional change noted. On both Texas sites, the gazelles survive on natural browse. Where there are feeders, competition from larger animals kept gazelles out. For breeding or restoring populations, flat-to-gently rolling terrain with ample browse is best. Shade and water are important, and any supplemental feed requires access. There also needs to be enough favored habitat to accommodate the adult males without dangerous conflict.

The Rufford Foundation, United Kingdom, the Whitley Fund for Nature, United Kingdom, and Parc Zoologique de Montpellier, France, funded the Mountain Zebra Project. Sarah Edwards received a post‐doctoral bursary from the University of Pretoria, South Africa.

Chagas disease, also known as American trypanosomiasis, is caused by the flagellate protozoan Trypanosoma cruzi. It is a significant health concern in South and Central America, where millions of people are infected or at risk of infection, and is an emerging health concern in the US. The occurrence of Chagas disease in natural environments is supported by mammal host species, but those primary species may vary based on geographic location. In South Texas, the primary host species for the disease is poorly understood, and required a field study to determine the spatial distribution of T. cruzi prevalence in free-ranging mammals. Our study objectives were to determine the spatial distribution and prevalence of T. cruzi parasites in free-ranging mammals. We compared T. cruzi prevalence among species, among vegetative communities, and among different topographies (i.e., floodplain versus upland). From December 2011 through December 2013, 450 blood and tissue samples from geolocated free-ranging wildlife mammal species were analyzed with the use of polymerase chain reaction to detect protozoan T. cruzi DNA. We also calculated mammal abundance with the use of mark-recapture methodology and recorded capture-site characteristics such as vegetation structure. We found that animals in grasslands had a significantly lower infection rate when summed across all species compared with animals in dense hardwoods and semi-improved woodlands (P=0.001). A higher percentage of infections were found in the lower-elevation floodplain-65% (28/43) of animals sampled, compared to upland areas-25% (9/36) of animals sampled. Our study suggested that common free-ranging meso-mammals supported T. cruzi in natural environments and are of public health concern in South Texas. Mitigation strategies should consider a range of management activities to include vegetation management, selective application of insecticides, and changes in human behavior in high-risk areas.

Background The movement behavior of an animal is determined by extrinsic and intrinsic factors that operate at multiple spatio-temporal scales, yet much of our knowledge of animal movement comes from studies that examine only one or two scales concurrently. Understanding the drivers of animal movement across multiple scales is crucial for understanding the fundamentals of movement ecology, predicting changes in distribution, describing disease dynamics, and identifying efficient methods of wildlife conservation and management. Methods We obtained over 400,000 GPS locations of wild pigs from 13 different studies spanning six states in southern U.S.A., and quantified movement rates and home range size within a single analytical framework. We used a generalized additive mixed model framework to quantify the effects of five broad predictor categories on movement: individual-level attributes, geographic factors, landscape attributes, meteorological conditions, and temporal variables. We examined effects of predictors across three temporal scales: daily, monthly, and using all data during the study period. We considered both local environmental factors such as daily weather data and distance to various resources on the landscape, as well as factors acting at a broader spatial scale such as ecoregion and season. Results We found meteorological variables (temperature and pressure), landscape features (distance to water sources), a broad-scale geographic factor (ecoregion), and individual-level characteristics (sex-age class), drove wild pig movement across all scales, but both the magnitude and shape of covariate relationships to movement differed across temporal scales. Conclusions The analytical framework we present can be used to assess movement patterns arising from multiple data sources for a range of species while accounting for spatio-temporal correlations. Our analyses show the magnitude by which reaction norms can change based on the temporal scale of response data, illustrating the importance of appropriately defining temporal scales of both the movement response and covariates depending on the intended implications of research (e.g., predicting effects of movement due to climate change versus planning local-scale management). We argue that consideration of multiple spatial scales within the same framework (rather than comparing across separate studies post-hoc) gives a more accurate quantification of cross-scale spatial effects by appropriately accounting for error correlation. Electronic supplementary material The online version of this article (doi:10.1186/s40462-017-0105-1) contains supplementary material, which is available to authorized users.

Knowledge of meso-mammal cave use is essential for natural resource managers, particularly in the management of endangered cave invertebrates. Scat left by meso-mammals represents significant nutrient inputs into the oligotrophic cave environment which can disrupt the invertebrate species composition and ecology. Since little is known about what constitutes typical timing or frequency of meso-mammal visitation, current management practices are largely speculative. Central Texas caves were historically associated with raccoons Procyon lotor, but with the loss of large predators and encroachment of woody vegetation, the now naturalized North American porcupine Erethizon dorsatum has become an established part of the local ecosystems whose effect on cave biology remains unknown. Our objective with this study was to quantify meso-mammal cave use according to seasons, time of day, weather conditions, as well ecological and physical cave characteristics. We monitored 30 caves by placing trail cameras at cave entrances for one year on Joint Base San Antonio-Camp Bullis military base just north of San Antonio, Texas. North American porcupines, raccoons, and Virginia opossums Didelphis virginiana were the three most commonly photographed meso-mammals (>87%). All meso-mammal groups showed significantly different cave use according to season, weather, and cave characteristics. Data suggested most meso-mammals were using caves for denning while raccoons and Virginia opossums also were feeding on resident invertebrate and rodent populations. In particular, Virginia opossum and raccoon, both potential predators of endangered species, showed greater use of caves containing endangered species. The results from our study represent an initial step in understanding meso-mammal cave use in central Texas.

Motivated by notions from coding theory, we study the generalized minimum distance (GMD) function δ I ( d , r ) of a graded ideal I in a polynomial ring over an arbitrary field using commutative algebraic methods. It is shown that δ I is non-decreasing as a function of r and non-increasing as a function of d. For vanishing ideals over finite fields, we show that δ I is strictly decreasing as a function of d until it stabilizes. We also study algebraic invariants of Geramita ideals. Those ideals are graded, unmixed, 1-dimensional and their associated primes are generated by linear forms. We also examine GMD functions of complete intersections and show some special cases of two conjectures of Tohaneanu–Van Tuyl and Eisenbud-Green-Harris.

Sus scrofa L. (Wild Pig) are known to eat the eggs of ground-nesting birds, but it is unknown to what extent they have an impact on populations of Colinus virginianus L. (Northern Bobwhite). We combined data from 2 prior studies conducted on a large ranch in South Texas to assess comparative habit use and selection by Wild Pigs and Bobwhites. Both species were distributed throughout the ranch, but their preferred habitats were very different. Bobwhites favored upland habitats, particularly areas with deep, sandy soils, while Wild Pigs favored low-lying habitats with clay soils. We conclude that depredation of Bobwhite nests by these invasive mammals may be restricted by the thermoregulatory requirement for Wild Pigs to stay near riparian areas. The extent of this effect will depend on the availability and spatial arrangement of water and riparian areas on the landscape.

Tragelaphus strepsiceros (greater kudu) has adapted to the harsh conditions of southern Africa’s mopani woodland. However, there is still limited information on the diet composition and selection of browse by greater kudu, particularly during the wet season. This poses a challenge to manage these ungulates effectively within their habitat. The study used rumen content to quantify the diet composition of greater kudu during the wet season. The study was conducted at the Sandown Game Farm, Limpopo Province, South Africa. Rumen samples were collected from four adult female and four adult male greater kudu culled in March 2015 and statistically analyzed using the t-test: paired two sample for means and Pearson’s correlation coefficient analysis. Findings show that Combretum apiculatum contributed most (43%) to the diet of greater kudu during the wet season. Other browse plant species were Sclerocarya birrea (24%), Colophospermum mopane (12%), and Acacia nigrescens (8%), with the contribution of the remaining species to the diet being insignificant. Leaves were the plant parts browsed most often and contributed 81% to the diet during this season. The remaining 19% of the diet consisted mainly of S. birrea fruit. Gender differences in diet selection were observed. The diet of female greater kudu consisted mainly of C. apiculatum (44%) and C. mopane (20%), while the diet of male greater kudu mostly contained S. birrea (38%) and C. apiculatum (34%). Implications for the management and conservation of greater kudu in mopani veld are discussed.

We investigate symbolic and regular powers of monomial ideals. For a square-free monomial ideal $I$ in $k[x_0, \ldots, x_n]$ we show $I^{t(m+e-1)-e+r)}$ is a subset of $M^{(t-1)(e-1)+r-1}(I^{(m)})^t$ for all positive integers $m$, $t$ and $r$, where $e$ is the big-height of $I$ and $M = (x_0, \ldots, x_n)$. This captures two conjectures ($r=1$ and $r=e$): one of Harbourne-Huneke and one of Bocci-Cooper-Harbourne. We also introduce the symbolic polyhedron of a monomial ideal and use this to explore symbolic powers of non-square-free monomial ideals., 15 pages. Fixed typo

Scat of meso-mammals provides nutrients to cave-obligate species. If there are too few nutrient inputs, cave-obligate species have no resources, but too much and caves are invaded by terrestrial species. Our goal for this project was to determine what combination of variables most influence meso-mammal cave use by building a multinomial regression model using data collected from cave entrances in central Texas. Variables of importance in our model relate to cave accessibility, including the raccoons' (Procyon lotor) and Virginia opossums' (Didelphis virginiana) greater dexterity, and the added bulk from the North American porcupine's (Erethizon dorsatum) quills. Our model can be used to predict and manage meso-mammal cave use in central Texas. This will be especially useful in this region because North American porcupine have only recently expanded their range into central Texas and their prolific nutrient inputs, previously absent from the ecosystem, could endanger cave-obligate species.

Introduction The spatial association dynamics of free-ranging cattle herds are not fully understood; however, they can have a direct influence on the spatial patterns of resource utilization. The aim of our study was to examine new analytical methods of identifying the spatio-temporal patterns of behavioral dynamics that determine cattle herd dispersal in the semi-arid rangelands of South Texas. We fitted 10 free-ranging cows with global positioning system collars and obtained positions every 5 min for each animal for 21-day trials, twice during the summer and winter period. We used an association pattern recognition software (ASSOC1) and the herd center of gravity to identify the spatial and temporal thresholds that defined dispersion-aggregation patterns and individual position to determine their relation to social dominance. Results The association pattern defining herd membership was that animals spent 70% of their time within 200 m of each other. Dominance ranking did not appear to influence association membership or position within the herd. The cattle showed a more dispersed distribution during summer, but in winter, herd members behaved in a more aggregated pattern. This distribution is contrary to patterns described in more northerly and mountainous regions. Conclusions The spatial thresholds of the cattle herd and the overall distance of all members to the center of the herd were smaller during winter and larger during summer, indicating that this study herd congregated during the winter and dispersed during the summer. Although this study uses a herd of 10 individuals in a 100 ha pasture to evaluate spatio-temporal dynamics, our results provide evidence of the ability of current tracking and spatial association tools to detect and quantify seasonal changes in cattle herd dispersion-aggregation patterns. The use of these data collection and analysis methods could prove useful in larger cattle herds, increase our understanding of herd spatio-temporal behavior, and subsequently help in the development of improved management practices.

Colophospermum mopane, commonly known as mopane, provides essential browse to the greater kudu (Tragelaphus strepsiceros), especially during the dry season. This study uses analysis of rumen-contents to quantify the use of C. mopane and other plants browsed by the greater kudu in the dry season. The study was conducted at the Sandown Game Farm, Musina Local Municipality, Limpopo Province of South Africa. Rumen samples were collected from three male and two female greater kudu culled in June 2014 and statistically analysed using t-Test: Paired Two Sample for Means and Pearson Correlation Coefficient analysis. Findings show that C. mopane contributed the most (47%) to the diet of the greater kudu during the dry season. Other important browse plants were Dichrostachys cineria (30%), Commiphora edulis (12%), Grewia bicolor (6%) and Combretum apiculatum (5%), with the contribution of T. prunioides and G. flava to the diet being insignificant. The plant parts mostly browsed were leaves, which contributed 75% to...

The presence of spines on woody plants has been shown to limit the loss of foliage to large mammalian browsers by restricting both bite size and biting rate. We tested the hypothesis that plant spines are also an effective defense against browsing by small mammals, such as rodents, that climb within the canopy of shrubs to harvest fruits, seeds, and foliage. Tame southern plains woodrats (Neotoma micropus) were allowed to harvest raisins impaled on the branches of blackbrush shrubs (Acacia rigidula Benth.) in five categories of spinescence: naturally spineless, moderately spiny, or very spiny branches, and moderately spiny and very spiny branches with the spines removed. Plant spinescence significantly reduced the woodrats foraging efficiency (P = 0.0001). Although plant spines are generally thought to be an evolved defense against browsing by ungulate herbivores, they may also reduce browsing by small mammals.

Northern bobwhites (Colinus virginianus) represent a valuable resource for upland game-bird hunters and the rural economies they support; however, bobwhite populations are declining across the United States. As ground-nesting birds, bobwhites are highly susceptible to mammalian predation during the breeding season. We placed global positioning collars on 6 coyotes (Canis latrans), 4 bobcats (Lynx rufus), and 11 raccoons (Procyon lotor) in Texas, USA, during the nesting season of bobwhites (April–August of 2009–2011) to assess their habitat selection and use, as well as determine the relative frequency with which they may encounter bobwhite nests. Overall, nightly encounter rate of predators with known bobwhite nest sites was low. Coyotes encountered nest sites 3 times more frequently than male raccoons and 7 times more frequently than bobcats. Female raccoons did not come within 50 m of any nest locations. The higher encounter rate of coyotes with bobwhite nest sites was associated with the similarity of habitat preference of coyotes and bobwhites for grasslands and grass–shrub habitats and the wide-ranging nocturnal paths of coyotes. Bobcats and raccoons had shorter nightly paths and mainly used habitats providing a greater degree of cover than is typically suitable for nesting bobwhites. Male raccoons were more mobile than females and made greater use of the grass–shrub habitat, and thus were more likely to encounter quail nests. Despite having lower individual encounter rates with bobwhite nest sites than did coyotes, male raccoons remain important predators of quail nests because they have the behavioral ability to attain greater population densities than those of the more territorial coyotes and bobcats. © 2014 The Wildlife Society.

Motivated by the work of Chudnovsky and the Eisenbud-Mazur Conjecture on evolutions, Harbourne and Huneke give a series of conjectures that relate symbolic and regular powers of ideals of fat points in $\mathbb P^n$. The conjectures involve both containment statements and bounds for the initial degree in which there is a non-zero form in an ideal. Working with initial degrees, we verify two of these conjectures for special line count configurations in projective 2-space over an algebraically closed field of characteristic 0., This version contains an alternate proof of the main combinatorial identity that was suggested by an anonymous referee. v3 also fixes some typos

We use two main techniques, namely, residuation and separators of points, to show that the Hilbert function of a certain fat point set supported on a grid complete intersection is the same as the Hilbert function of a reduced set of points called a partial intersection. As an application, we answer a question of Tohǎneanu and Van Tuyl which relates the minimum Hamming distance of a special linear code and the minimum socle degree of the associated fat point set.

The ability to age white-tailed deer (Odocoileus virginianus) is essential for population management, but field-aging techniques based on visual assessment of tooth-wear patterns lack accuracy. We used regression analysis to relate tooth measurements to age of 54 known-age wild South Texas (USA) male deer captured from 2002 to 2012. Using 9 animals/age class, from 2.5 to 7.5 years old, we measured cusp height and widths of each layer of enamel or dentine within each cusp of the third premolar (P3) on both left and right sides of the lower jaws. We found a linear relationship between age and dentine width (D), particularly within the anterior buccal cusp of P3 on the right jaw (r2 = 0.727). The regression equation, Age = 1.819 + (1.755 × D) provided a predictive aging model. We validated this model with 140 jaws from different known-age male deer within the same age range and from the same locations. Placement within the correct year class was achieved for 48% of male deer, and 90% were classified within 1 year of their actual age. This accuracy was greater than that achieved by 27 Wildlife Society members who correctly aged 28% of a subsample of the same jaws by tooth-wear patterns. Thus, using tooth measurements to age deer provided more accurate age estimation than visual tooth-wear methods. The dentine method is particularly useful for deer ≥3.5 years old. This technique may need to be calibrated with measurements from local known-aged deer before being used to age animals from regions beyond South Texas. © 2013 The Wildlife Society.

Contact rates vary widely among individuals in socially structured wildlife populations. Un- derstanding the interplay of factors responsible for this variation is essential for planning effective disease management. Feral swine (Sus scrofa ) are a socially structured species which pose an increasing threat to livestock and human health, and little is known about contact structure. We analyzed 11 GPS data sets from across the United States to understand the interplay of ecological and demographic factors on vari- ation in co- location rates, a proxy for contact rates. Between- sounder contact rates strongly depended on the distance among home ranges (less contact among sounders separated by >2 km; negligible between sounders separated by >6 km), but other factors causing high clustering between groups of sounders also seemed apparent. Our results provide spatial parameters for targeted management actions, identify data gaps that could lead to improved management and provide insight on experimental design for quantitat - ing contact rates and structure.

The aim of this study was to give an overview of the prevalence of contact allergy to active ingredients and excipients of topical medications across Europe.Retrospective analysis of data collected by the European Surveillance System on Contact Allergies (www.essca-dc.org) with substances applied to consecutively patch tested patients, 2009-2012, in 54 departments in 12 European countries.In view of the varying composition of the baseline series used in the previously mentioned departments and countries, between 58 833 (lanolin alcohols) and 16 498 patients (sodium metabisulfite) were patch tested with the topical agents covered in this study. Among these, positive (allergic) reactions were most commonly observed to sodium metabisulfite (3.12% positive), followed by propolis (2.48%), Compositae mix (1.73%), lanolin alcohols (1.65%) and caine mix III (benzocaine, cinchocaine and tetracaine; 1.27%).Several of the substances warrant routine screening for contact allergy, i.e. patch testing in a baseline series. However, in view of a vast number of other topical agents, additional patch testing with the suspect topical drug preparations (including natural remedies and cosmetics) is warranted. In the event of a positive test to the (pharmaceutical) product, single ingredients should be tested individually to precisely identify the hapten(s). Copyright © 2016 John WileySons, Ltd.

Uneven use of grasslands and savannas by livestock has a significant impact on ecosystem productivity, biodiversity, and function. In studies of livestock distribution, global positioning systems (GPS) collars are frequently used and the rapid rate of technological improvement has brought new opportunities to collect extremely large amounts of very accurate spatial information. However, these advances also pose statistical challenges associated with the analysis of large, temporally correlated, datasets. Our main goal was to find the optimal sampling time intervals for GPS collar schedules when studying livestock distribution in semi-arid ecosystems. The schedule must provide maximum spatio-temporal information while avoiding problems of autocorrelation of sequential locations to provide a methodology that is both practical and statistically valid. We used GPS collar data collected in the Southwestern region of the United States. In each study cattle were tracked and data were recorded every 5 min. Location information from the 5-min GPS fixes were subsampled into 10, 20, 30, 60, 90, 120, 150, 180, 240, 300, 360, and 420-min regular intervals. We calculated the Euclidean distance between pairs of successive locations then conducted correlation analyses to determine the degree of similarity between successive traveled distances. We then selected two correlated and two non-correlated time-interval datasets to compare estimates of kernel home range and minimum convex polygon areas. Successive Euclidean distances between GPS locations were significantly correlated when time intervals were

We study Hilbert functions of certain non-reduced schemes A supported at finite sets of points in projective space, in particular, fat point schemes. We give combinatorially defined upper and lower bounds for the Hilbert function of A using nothing more than the multiplicities of the points and information about which subsets of the points are linearly dependent. When N=2, we give these bounds explicitly and we give a sufficient criterion for the upper and lower bounds to be equal. When this criterion is satisfied, we give both a simple formula for the Hilbert function and combinatorially defined upper and lower bounds on the graded Betti numbers for the ideal defining A, generalizing results of Geramita-Migliore-Sabourin (2006). We obtain the exact Hilbert functions and graded Betti numbers for many families of examples, interesting combinatorially, geometrically, and algebraically. Our method works in any characteristic. AWK scripts implementing our results can be obtained at http://www.math.unl.edu/~bharbourne1/CHT/Example.html ., Comment: 23 pages; changes have been made following suggestions of the referee; explicit statements are now included for dimensions greater than 2, hence the title no longer mentions the plane; however the content is largely the same as in the previous version; this version is to appear in the Journal of Pure and Applied Algebra

Spatial distribution, population density, and reproductive success of many wildlife species may be altered by changes in vegetation composition, habitat structure, and availability of food. Altered distributions of key herbivores such as white-tailed deer (Odocoileus virginianus) may impact all of these factors. Our objective was to determine the direct and indirect effects of supplemental feeding of deer on rodent populations in south Texas. We modeled effects of supplemental feeding and habitat change due to deer browsing through surveys of rodents. Rodents have a short generation time and populations respond quickly to change, so they are a suitable indicator of changes in habitat structure brought about by deer browsing pressure. We sampled rodent populations near to and far from deer feeders within twelve 81-ha enclosures containing three different densities of deer with and without supplemental feed. The three deer densities were low (8.1 ha/deer), medium (3.2 ha/deer), and high (2 ha/deer). We conducted rodent trapping during March and April of 2007 and 2008. Abundance of rodents was much higher (P < 0.001) in 2008 than in the previous year due to an increase in rainfall. However, we found little effect of deer density, supplemental feeding of deer, or distance from deer feeders on rodent populations. Thus we conclude that supplemental feeding of deer and deer density had little influence on rodent communities in this environment. Rodent species native to semi-arid environments are probably adapted to large changes in vegetative productivity brought about by the highly variable annual rainfall patterns, therefore they can adapt to the less abrupt habitat changes resulting from changing densities of deer. Conservation concerns that providing supplemental feed to deer in semi-arid rangeland will disrupt the ecology of the land through changes in rodent populations were not supported. 2011 The Wildlife Society.

Assessing numerical response of northern bobwhites (Colinus virginianus) to habitat improvement in semi-arid rangeland often is confounded by responses of populations to highly variable patterns of rainfall. During 2 years of above-average rainfall, we investigated abundance of northern bobwhites relative to type of range and treatments to reduce brush on seven ranches in southern Texas. We expected response of populations to treatment of land to be more evident when northern bobwhites were released from constraints of low precipitation. However, main factors dominating abundance were rainfall during the previous growing season and type of range. Greatest numbers of calls were in mid- productivity rangeland (potential production of forage 2,000-3,900 kg/ha), especially sandy loam, clay loam, sandy, and gravelly ridge. Treatments to reduce brush increased abundance of northern bobwhites to a limited extent and were most effective when large blocks of land were treated. Techniques that kill brush (root-plowing) were more successful in increasing populations than top- removal methods (roller-chopping). Leaving strips or mottes (large clumps of living brush and trees) in cleared areas did not enhance populations, although we caution that retaining some brush cover may be important to survival of northern bobwhites in drier years and in situations where herbaceous cover is less abundant. RESUMEN—Determinar la respuesta numerica de codornices nortenas (Colinus virginianus )at ecnicas para mejorar el habitat en pastizales semiaridos es confundido por las respuestas poblacionales a patrones altamente variables de precipitacion. Durante dos anos de precipitacion ma alta que la media, investigamos la abundancia de codornices con respecto al tipo de pastizal y tratamientos para reducir arbustos en siete ranchos en el sur de Texas. Esperamos la respuesta de la poblacion al tratamiento de la tierra ser mas evidente cuando las codornices fueron liberadas de los apremios de baja precipitacion. Sin embargo, los factores mas dominantes para determinar la abundancia fueron la precipitacion durante la estacion de crecimiento anterior y el tipo de pastizal. Mas silbidos fueron registrados en los pastizales de productividad mediana (produccion de forraje potencial de 2.000-3.900 kg/ha), especialmente en pastizales con suelos marga-arenosos, marga-arcillosos, arenosos, y pastizales en bordes pedregosos. Tratamientos para reducir arbustos aumentaron la abundancia de codornices a un grado limitado y fueron mas eficaces cuando terrenos grandes fueron tratados. Los tratamientos de remocion de arbustos (remocion de rao ´ces) fueron mas exitosos para incrementar la poblacion que los metodos de remocion superior (la eliminacion de biomasa aerea). Dejando bandas o grandes grupos de arbustos y arboles en areas despejadas no mejorolas poblaciones, aunque consideramos importante indicar que retener alguna cobertura arbustiva podro ´a ser importante para la supervivencia de codornices en anos mas secos y en situaciones donde la cobertura herbacea es menor.

The significant impact of extant carnivores, particularly spotted hyenas, on the depositional history and physical characteristics of archaeofaunal and paleontological assemblages is well recognized. We focus on the behavioral ecology of extant spotted hyenas (Crocuta crocuta) in relation to bone accumulations produced by one East African clan at communal dens. Limbs and skulls of prey animals more frequently appear at dens than do other carcass portions. These items reflect the relative abundance of prey species near dens; carnivore remains are poorly represented. Comparative analysis reveals that bones are deposited far more slowly (Crocutadens than at dens of either brown (Parahyaena brunnea) or striped (Hyaena hyaena) hyenas. We propose that extantCrocutabone accumulation rates and sizes are likely affected by prey species abundance, clan size, social interactions within the clan, and the type and availability of den sites. We also suggest that the potential for intraspecific behavioral variability in bone accumulation patterns is important when comparisons are made among spotted hyena populations and across hyena species. For example, accumulation patterns may be dramatically influenced by the temporal span, potentially ranging from days to hundreds or thousands of years, in which bones are collected, depending on the species-specific history of occupation at a given site. Understanding the behavioral and ecological variability likely to influence bone accumulation patterns at dens used by different hyaenids will allow taphonomists and zooarchaeologists to refine their knowledge of mechanisms underlying site formation processes and potential causes of variability in deeper-time den assemblages.

The Caribbean region is one of the five leading biodiversity hotspots in the world. Analysis of the spatial structure of critical habitats and how it affects endemic species in this region is essential baseline information for biodiversity monitoring and management. We quantified and evaluated the spatial structure and connectivity of depression forests on Mona Island and their potential impact on Mona Island rock iguana habitat, as a framework to assess spatial distribution, connectivity, and the issue of scale in small and widely dispersed habitats. Using IKONOS imagery, we mapped and delineated depression forests at four different scales (minimum mapping units

Management of rangelands has changed substantially over the past few decades; today there is greater emphasis on wildlife management and increased interest in using natural disturbances such as fire to manage rangeland plant and animal communities. To determine the effect of prescribed fires on the distribution of white-tailed deer (Odocoileus virginianus), we used Global Positioning System (GPS) collars to monitor the movements of bucks and does during four, month-long, trials before and during the year after implementation of three late summer burns. Deer were expected to increase their use of burned areas to take advantage of fresh plant growth after the disturbance. However, the only increased use of burns occurred 1–2 months after treatment. The presence of cattle did not limit deer use of burns. Low use of burned areas was attributed to drought conditions, which limited vegetation regrowth. Other than a brief flush of fresh grass in autumn, no changes in plant cover could be ascribed to the burns. Thus, in semi-arid areas, use of prescribed burns to reduce brush cover and increase forb production for deer may not be successful, at least in the short-term, if lack of rainfall limits regrowth of vegetation.

In order to optimize production, range managers need to understand and manage the spatial distribution of free-ranging herbivores, although this task becomes increasingly difficult as ranching operations diversify to include management of wildlife for recreational hunting. White-tailed deer are sympatric with cattle throughout much of their range and are a valuable commodity in southern rangelands. The spatial distribution of deer and cattle was monitored over 1 year during four trials each lasting 12 days. In each trial six white-tailed deer (three bucks, three does) and nine cows were fitted with Global Positioning System (GPS) collars. Collars were scheduled to take a position location every 5 min to determine animal location. These data were analyzed to study animal-to-animal interactions. To minimize problems of spatial autocorrelation, data were thinned to hourly locations for assessing animal home ranges and distributions. Although there was extensive overlap in spatial distributions of deer and cattle the species exhibited strong temporal separation. The mechanism was probably a combination of avoidance of cattle by deer and different habitat requirements. Close interactions were rare, however, individual deer did not show avoidance of cattle until they were within 50 m of each other. Species distributions overlapped mainly on the most productive ecological sites such as clay loam soils and riparian areas which were favored by both species. Cattle avoided rocky terrain, so deer had almost exclusive use of rocky areas including the productive deep soil drainage areas within them. Does particularly favored these areas and the riparian areas while bucks favored the more open clay loam sites. In this shrub-dominated system both deer and cattle were often located close to ranch roads, and cattle especially used roads as paths of least resistance. Cattle were closely associated with water sources, but deer did not stay long near water or at supplemental feeding sites. Concerns that cattle will displace deer into marginal habitats, or that deer will over utilize vegetation near water and feeders, were not supported.

Eisenbud and Popescu showed that certain finite determinantal subschemes of projective spaces defined by maximal minors of adjoint matrices of homogeneous linear forms are related by Veronese embeddings and a Gale transform. We extend this result to adjoint matrices of multihomogeneous multilinear forms. The subschemes now lie in products of projective spaces and the Veronese embeddings are replaced with Segre embeddings.

It has been conjectured by Eisenbud–Green–Harris that lex-plus-powers ideals exhibit extremal conditions among all homogeneous ideals containing a regular sequence of forms in fixed degrees. In the same spirit, we consider a family of homogeneous ideals in k [ x , y , z ] which contain a regular sequence of forms F , G ∈ k [ x , y ] and compare the growth of these ideals with special monomial ideals sharing similar properties.

Given a squarefree monomial ideal $I \subseteq R =k[x_1,\ldots,x_n]$, we show that $\widehat\alpha(I)$, the Waldschmidt constant of $I$, can be expressed as the optimal solution to a linear program constructed from the primary decomposition of $I$. By applying results from fractional graph theory, we can then express $\widehat\alpha(I)$ in terms of the fractional chromatic number of a hypergraph also constructed from the primary decomposition of $I$. Moreover, expressing $\widehat\alpha(I)$ as the solution to a linear program enables us to prove a Chudnovsky-like lower bound on $\widehat\alpha(I)$, thus verifying a conjecture of Cooper-Embree-H\`a-Hoefel for monomial ideals in the squarefree case. As an application, we compute the Waldschmidt constant and the resurgence for some families of squarefree monomial ideals. For example, we determine both constants for unions of general linear subspaces of $\mathbb{P}^n$ with few components compared to $n$, and we find the Waldschmidt constant for the Stanley-Reisner ideal of a uniform matroid., Comment: 26 pages. This project was started at the Mathematisches Forschungsinstitut Oberwolfach (MFO) as part of the mini-workshop "Ideals of Linear Subspaces, Their Symbolic Powers and Waring Problems" held in February 2015. Comments are welcome. Revised version corrects some typos, updates the references, and clarifies some hypotheses. To appear in the Journal of Algebraic Combinatorics

We present a novel technique using a video serial interface to link a motion-activated, infrared video camera and a weigh-scale to measure supplemental feed consumption by wildlife. This “video-scale” allows us to quantify consumption of various feeds by individual animals to an accuracy of 5 g and to record feeding duration to the second. Using intake rate and total time spent feeding, we calculated comparative use of supplemental feed by animals categorized by species, age, and sex. We present preliminary data on feed consumption and intake rates of wild and tame white-tailed deer (Odocoileus virginianus) and raccoons (Procyon lotor) eating shelled corn, pelleted supplement, and whole cottonseed. Other uses and limitations of the video-scale are discussed.

We investigate the risk that supplemental feeding of white-tailed deer (Odocoileus virginianus) to improve trophy quality may degrade rangeland through overutilization of forage plants near the feeders. We divided a South Texas ranch into 6 areas (each 1100 ha). Supplemental feed was provided year-round in a centrally placed feeder in 3 areas, no supplement was provided in the 3 control areas. Radio-telemetry collars were fitted on 2 bucks and 2 does in each area. Spatial distribution of these deer was assessed using the CALHOME program. Feed supplementation did not alter home range size of does but did reduce their 50% core area. Bucks without supplemental feed showed 2 spatial strategies; sedentary bucks had home range distributions similar to supplemented bucks, while commuter bucks moved to supplemented areas during the breeding season. Browsing pressure near feeders and control sites was assessed by measuring consumption of seedlings set in arrays radiating from feeders and control points. Deer browsing was heavier near feeders than at the control sites, and the probability of a seedling being browsed increased with proximity to the feeder. We caution against long-term supplemental feeding in fixed locations because of the potential for localized range degradation around the feeders.

The use of food plots, supplemental feeding, and baiting has been a common and legal practice in Texas for many years. There is now controversy as to whether Texas Parks and Wildlife Department should include this extra nutrition as part of their carrying capacity estimates used to determine harvest permits for private landowners. Managers should remember that nutrition is only one component of carrying capacity, which includes water, shelter, and space as well. Extensive data exists about the potential negative impact of feeding on deer. Studies in Texas (Murden and Risenhoover 1993) have shown that fed deer (Odocoileus virginianus) can degrade rangeland by overconsuming high-quality plants and underconsuming low-quality plants. Guiterrez (1999) did not find that effect when South Texas deer were offered winter food plots. Donier et al. (1997) found in Minnesota that winter supplementation increased browse pressure within 900 m of feeders. Other reports (Williamson 2000) show increased browse pressure within a 1-mile radius of feeders, perhaps due to concentration of deer. Cooper et al. (2002) found 50% kernal home range sizes of fed deer were half that of unfed deer and that browse pressure near the feeder was 7 times that of unfed deer. Supplemental feeding has been suspected of contributing to the spread of tuberculosis in deer, chronic wasting disease in elk (Cervus canadensis) and deer, and brucellosis in elk and bison (Bison bison; Williamson 2000). Crowding due to supplemental feeding led to fighting and injuries in Michigan deer (Ozoga 1972). Feeding has actually led to starvation in deer due to increases in population when feeding was initiated (McCullough 1977, Schmitz 1990). Supplemental feed is consumed by nontarget species, possibly leading them to pass disease and to attract predators. Cooper and Ginnett (2000) found decreased survivorship of simulated turkey nests within 400 m of deer feeders in Texas. In 1998 we found illegal levels of aflatoxin in 40% of 100 randomly purchased bags of “deer corn” in Texas (N. Wilkins, Texas Cooperative Extension, USA, unpublished data). The ecological significance of deer feeding and baiting is only part of the issue. Feeding leads to ethical questions as well. Feeding is part of the domestication process, along with fencing, breeding, and health programs that, due to their expense, may lead to the desire for private ownership of wildlife. Baiting, likewise, adds to the advantages of the hunter over the hunted and may decrease hunter satisfaction and increase concerns of the antihunters and the nonhunting public (Ortega y Gasset 1995). Deer managers and agency personnel should review the data presented here and incorporate it into their decision making when considering feeding or baiting of deer.

We examined regrowth architecture of 4 species of savanna shrubs following 4 levels of defoliation. Defoliation had little effect on the regrowth architecture of honey mesquite (Prosopis glandulosa), which is rarely browsed by mammalian herbivores. The 3 acacia species (Acacia berlandieri, A. greggii, A. schaffneri) responded to defoliation by increasing leaf and spine density on the regrowth branches, but spine length and branching architecture remained unchanged. Only A. greggii, which is a preferred food plant of many browsers, exhibited an increase in the number and length of current annual growth branches in response to defoliation. The changes in plant architecture due to defoliation had little effect on the subsequent feeding behavior of captive white-tailed deer (Odocoileus virginianus). Food intake rate of the deer was most strongly related to internode distance, a parameter not significantly altered by defoliation. This suggests that the architectural responses of these shrubs to defoliation may not provide increased defense against browsing by co-evolved mammals.

Preface.- Differential Graded Commutative Algebra.- Secant Varieties.- Fat Points and Symbolic Powers.- An Introduction to Stanley-Reisner Rings.- Combinatorial Resolutions.- Geometric Properties of the Tor Algebra Structure for Trivariate Monomial Ideals.- Interactions Between Linear Algebra and Algebraic Geometry.- Fat Points.- Primary Decomposition of Certain Permanental Ideals.

These notes are a record of lectures given in the Workshop on Connections Between Algebra and Geometry at the University of Regina, May 29–June 1, 2012. The lectures were meant as an introduction to current research problems related to fat points for an audience that was not expected to have much background in commutative algebra or algebraic geometry (although Sects. 8 and 9 of these notes demand somewhat more background than earlier sections).

Guided by evidence coming from a few key examples and attempting to unify previous work of Chudnovsky, Esnault-Viehweg, Eisenbud-Mazur, Ein-Lazarsfeld-Smith, Hochster-Huneke and Bocci-Harbourne, Harbourne and Huneke recently formulated a series of conjectures that relate symbolic and regular powers of ideals of fat points in ${\bf P}^N$. In this paper we propose another conjecture along the same lines (Conjecture 3.9), and we verify it and the conjectures of Harbourne and Huneke for a variety of configurations of points., Version 3 adds Remark 3.11, regarding recent counterexamples, 14 pages (version 2 added new conjecture, Conjecture 3.9, and fixed typos with slight change to abstract)