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Creating product line architectures
The creation and validation of product line software architectures are inherently more complex than those of software architectures for single systems. This paper compares a process for creating and evaluating a traditional, one-of-a- kind software architecture with one for a reference software architecture. The comparison is done in the context of PuLSE-DSSA, a customizable process that integrates both product line architecture creation and evaluation
Bottom-Up and Top-Down Controls on Food Webs in Headwater Streams
Headwater streams account for 70% of stream channel length in the USA and are important as hotspots of nutrient uptake and native biodiversity. Biofilm, the mixed auto- and heterotrophic microbial community covering stream substrates, is where the majority of nutrient processing occurs, and forms the base of stream food webs, particularly in heavily shaded, oligotrophic streams. Both bottom-up (e.g., nutrients, light) and top-down (i.e., consumption) processes are known to affect periphyton, the autotrophic component of biofilm, but little is known about what controls the biofilm community as a whole. Top-down effects are common in streams, where fish are often the top predator and can cause cascading effects. However, salamanders – not fish – are the top predators in many small headwater streams, and the top-down effects of salamanders on stream food webs have received much less attention. I used experimental and observational approaches to investigate the role of top-down and bottom-up controls on headwater stream food webs. Specifically, I used stream mesocosms with two salamander species, Eurycea bislineata and Gyrinophilus porphyriticus, alone or in combination, to test the effects of salamander community composition on benthic and emergent macroinvertebrate density, biomass and community composition. To assess the relative importance of bottom-up and top-down determinants of biofilm biomass, I used a combination of stream surveys and pre-existing stream chemistry data from across the oligotrophic headwater streams of the Hubbard Brook Experimental Forest (HBEF). My experiment showed that stream salamanders alter benthic macroinvertebrate densities, but only when G. porphyriticus occurs alone, as it consumes E. bislineata, the smaller species, when it is present. This intraguild predation removes the top-down effects of G. porphyriticus on benthic macroinvertebrates. In my stream surveys, bottom-up variables (i.e., aspect, canopy cover, nutrients and pH) determined biofilm biomass, not salamander occupancy or benthic macroinvertebrate biomass. However, I did not encounter streams with the specific salamander community (i.e., G. porphyriticus present and E. bislineata absent) shown to produce top-down effects in my experimental study. My results demonstrate that salamanders can exert top-down control on benthic macroinvertebrate communities. This effect is, however, dependent on the salamander species present, and can be removed by intraguild interactions between salamander species. Furthermore, bottom-up factors, in particular light, appear to play the primary role in determining biofilm biomass. Despite prior evidence for the dominance of heterotrophic microbes in biofilms at the HBEF, the importance of light in controlling biofilm biomass suggests that the autotrophic component of these biofilms may be disproportionately important, and emphasizes the importance of understanding both the auto-and heterotrophic components of stream biofilms. My work links the rich history of research on stream salamander community ecology to broader studies of stream food webs, providing new avenues for future research
Federal Regulation of Emerging Genetic Technologies
Over the past ten years scientists have perfected revolutionary techniques in the field of genetic engineering. Although this new technology promises to have enormous commercial and industrial value, some scientists fear that the risks accompanying genetic experimentation may outweigh its social benefits. In their Article Professor McGarity and Mr. Bayer examine the legal debate over how government should regulate this emerging technology. After describing various genetic engineering techniques and the risks underlying their use, Professor McGarity and Mr. Bayer discuss the elements of a regulatory framework adequate to handle the new technology and assess the existing regulatory structure in terms of a more appropriate framework. They conclude that the appropriate existing federal agencies immediately should undertake data collection and risk assessments to identify the dangers in the experimentation, manufacture, and practical use of genetically altered micro-organisms. Professor McGarity and Mr. Bayer recommend that Congress be prepared to enact new legislation if the existing regulatory framework fails to meet the challenge of this exciting new technology
Division, adjoints, and dualities of bilinear maps
The distributive property can be studied through bilinear maps and various
morphisms between these maps. The adjoint-morphisms between bilinear maps
establish a complete abelian category with projectives and admits a duality.
Thus the adjoint category is not a module category but nevertheless it is
suitably familiar. The universal properties have geometric perspectives. For
example, products are orthogonal sums. The bilinear division maps are the
simple bimaps with respect to nondegenerate adjoint-morphisms. That formalizes
the understanding that the atoms of linear geometries are algebraic objects
with no zero-divisors. Adjoint-isomorphism coincides with principal isotopism;
hence, nonassociative division rings can be studied within this framework.
This also corrects an error in an earlier pre-print; see Remark 2.11
АНАЛІЗ ФАКТОРІВ, ЩО ВИЗНАЧАЮТЬ ОСОБИСТІСНУ СТІЙКІСТЬ ЗА УМОВ СОЦІАЛЬНИХ РЕПРЕСІЙ
On the basis of the consideration of theoretical sources from the contiguous areas of psychological science some intrapersonal and external factors which could be regarded as auxiliary in the process of personality’s capture of destructive influences of the soviet management system are selected.На основе рассмотрения теоретических источников из смежных областей психологической науки выделены некоторые внутриличностные и внешние факторы, которые могли выступить как вспомогательные в овладении личностью разрушительных влияний советской административной системы.На основі розгляду теоретичних джерел із суміжних областей психологічної науки виокремлено деякі внутрішньоособистісні та зовнішні фактори, що могли виступити як допоміжні в опануванні особистістю руйнівних впливів радянської адміністративної системи
ПРОБЛЕМА СУБ’ЄКТИВНОГО ОБРАЗУ СВІТУ В РОБОТАХ ВІТЧИЗНЯНИХ ТА ЗАРУБІЖНИХ АВТОРІВ
Наведено стислий огляд основних теорій та концепцій психологічної науки, що стосуються опису та структури феномену суб’єктивного образу світу. Матеріал може бути застосований із метою розширення курсу лекцій із дисципліни «Загальна психологія», розділ – психологія пізнання
Do effective properties for unsaturated weakly layered porous media exist? An experimental study
International audienceIn a multi-step outflow experiment we found that a weak heterogeneity within a sand column prevents the estimated effective hydraulic parameters from being unique. We compared vertical water content profiles calculated from these parameters with profiles measured by x-ray attenuation. A layered material model based on x-ray data was able to reproduce the outflow curve and also the water content distribution inside the column. We also calculated effective parameters for the layered model turned upside down and obtained large differences to the set of values of the original sample
The orbifold cohomology of moduli of genus 3 curves
In this work we study the additive orbifold cohomology of the moduli stack of
smooth genus g curves. We show that this problem reduces to investigating the
rational cohomology of moduli spaces of cyclic covers of curves where the genus
of the covering curve is g. Then we work out the case of genus g=3.
Furthermore, we determine the part of the orbifold cohomology of the
Deligne-Mumford compactification of the moduli space of genus 3 curves that
comes from the Zariski closure of the inertia stack of M_3.Comment: 29 pages, 2 figures. Minor changes, to appear in Manuscripta Mat
Control of interlayer exchange coupling in Fe/Cr/Fe trilayers by ion beam irradiation
The manipulation of the antiferromagnetic interlayer coupling in the
epitaxial Fe/Cr/Fe(001) trilayer system by moderate 5 keV He ion beam
irradiation has been investigated experimentally. It is shown that even for
irradiation with very low fluences (10^14 ions/cm^2) a drastic change in
strength of the coupling appears. For thin Cr-spacers (below 0.6 - 0.7 nm) the
coupling strength decreases with fluence, becoming ferromagnetic for fluences
above (2x10^14 ions/cm^2). The effect is connected with the creation of
magnetic bridges in the layered system due to atomic exchange events caused by
the bombardment. For thicker Cr spacers (0.8 - 1.2 nm) an enhancement of the
antiferromagnetic coupling strength is found. A possible explanation of the
enhancement effect is given.Comment: Submitted to PR
THE RELATION OF ADOLESCENTS’ SOVEREIGNTY OF PSYCHOLOGICAL SPACE WITH COPING STRATEGIES AND INTRAPERSONAL CONFLICTS
Розглянуто й обґрунтовано актуальність проблеми порушення психологічного простору юнаків і зв’язку даного явища із їх вибором копінг-стратегій і наявністю внутрішньоособистісних конфліктів. Наведено результати емпіричного дослідження, згідно із якими для молодих людей із порушеною суверенністю психологічного простору характерне уникнення як копінг-стратегія. З’ясовано, що молоді, суверенність психологічного простору яких порушувалася, притаманна наявність конфлікту у внутрішньоособистісній сфері.Рассмотрены результаты исследования взаимосвязи суверенности психологического пространства молодых людей с выбором ими копинг-стратегий и присущих им внутриличностных конфликтов. Описаны результаты эмпирического исследования, в соответствии с которыми молодые люди с нарушенными психологическими границами отдают предпочтение бегству как копинг-стратегии. В ходе исследования также доказано, что субъектам с депривированными границами суверенности психологического пространства свойственны конфликты во внутриличностной сфере.Background. Every person within his or her lifetime forms a kind of psychological space which includes one’s body, territory, social relations, habits, belongings, and values. Breaking one’s personal autonomy by others may be viewed aggressively and hostilely. But this is with opposition to the surrounding when one determines and protects the borders of his or her space. The objective of this study is to reveal a possible relation of adolescents’ personal space with the type of coping strategies they choose and intrapersonal con?icts they may experience. Method. The relation between psychological space, coping behavior and intraper-sonal con?icts was assessed by strategy of ?nding differences between non-equivalent groups (?*-Fischer coef?cient) using the following psycho-diagnostic instruments: «The sovereignty of psychological space» (Nartova-Bochaver, 2004), «The level of interrelation of a value and its accessibility in different life spheres» (Fantalova, 1996), Coping Styles Questionnaire adapted by T.L. Krukova (Krukova, 2007; Lazarus & Folkman, 1988).Sample: 40 research participants (20 male and 20 female), aged from 18 to 24.Results. Adolescents with healthy personal borders tend to choose social support (?*=1.71за p<.05) and planning (?*=1.43 за p<.08) as coping strategies more often while teenagers with either rigid or drained psychological borders prefer escape (?*=1.65 за p<.05) and are characterized by experiencing intrapersonal con?icts (?*=1.78 за p<.04 and ?*=2.06 за p<.02). Conclusion. Groups of adolescents with healthy and either rigid or drained personal borders appeared to differ in coping strategies they choose and intrapersonal con?icts they experience.Further research is desirable to test the cross-age consistency of the discovered effect
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