Analysis of Heads-Up Display Quickening Versus Handling Qualities

This study investigated an analytical means of selecting the quickening time constant for the standardized Heads-Up Display flight path marker. The theoretically determined time constant allowed a faster, less resource intensive means of selecting the quickening time constant. The theoretically best time constant for pilot-aircraft handling qualities was equal to the airframe pitch attitude high frequency zero time constant, Tθ2. Flight test indicated an empirical, more labor intensive method yielded better handling qualities, even though paper analysis indicated the theoretical method was better. The theoretically determined time constant gave slightly lower handling qualities. but was less costly to implement than the empirical method

Poly(ethylene) glycols and mechanochemistry for the preparation of bioactive 3,5-disubstituted hydantoins

International audienceMechanochemistry was effective for the preparation of 3,5-disubstituted hydantoins from a-amino methyl esters, using either 1,1 0-carbonyldiimidazole (CDI) or alkyl isocyanates. The preparation of the antimicrobial additives, 3-allyl-5,5 0-dimethyl hydantoin (ADMH) and 1-chloro-3-ethyl-5,5 0-dimethyl hydantoin (CEDMH) were performed by grinding. A chlorination reaction, never described before by mechanochemistry was achieved by Ca(ClO) 2 , while the preparation of the bioactive anticonvulsant marketed drug ethotoin was achieved by a novel approach based on poly(ethylene) glycol (PEGs) assisted grinding

COMPARISON OF MOLECULAR AND GENETIC PROPERTIES OF PINE (Pinus sylvestris L.) SEED PLANTATIONS IN BOSNIA AND HERCEGOVINA

U radu je analizirana je genetička struktura dvije sjemenske plantaže običnog bora (Pinus sylvestris L.) sa 40 klonova (Kozji grm) i 20 klonova (Šamin gaj). Za analizu su uporabljeni izoenzimski biljezi, ukupno 9 enzimskih sustava, na ukupno 12 gen lokusa. Ukupno 55 alela, u obje klonske sjemenskim plantaže. U multiklonskoj plantaži \u27\u27Koziji grm\u27\u27 registrirano 45, a u sjemenskoj plantaži \u27\u27Šamin gaj\u27\u27 35 alela različitih alela. Genetička raznolikost procijenjena je srednjim brojem alela po lokusu (A/L). Dobivena je vrijednost od 3,83 za sjemensku plantažu Kozji grm i 2,91 za plantažu Šamin gaj. Srednji broj genotipova po lokusu (G/L) je iznosio 5,16 za sjemensku plantažu Kozji grm i 3,58 za sjemensku plantažu Šamin gaj. Srednja stvarna heterozigotnost klonova u sjemenskoj plantaži Kozji grm iznosi 0,2833, a u sjemenskoj plantaži Šamin gaj srednja heterozigotnost je 0,3166. Srednja teorijska heterozigotnost za plantažu Kozji grm iznosi 0,3366, a za sjemensku plantažu Šamin gaj 0,3491.The paper analyses the genetic structure of the pine (Pinus sylvestris L.) clones in the multiclone seed plantations of Kozji Grm (KG) and Šamin Gaj (ŠG). The clones in both seed plantations originate from natural populations of common pine in Bosnia and Hercegovina; KG (40 clones): Gornji Janj – 10 clones, Klekovača 7, Kaljina Bioštica 16, Romanija Glasinac 6, Igman 1, while the ŠG plantation contains 20 clones from one population (Igman). The genetic structure was analysed using 9 enzyme systems upon altogether 12 gene loci. Altogether 55 different alleles were observed: in KG plantation 45 alleles were seen, while in ŠG plantation there were 35 alleles. To estimate the genetic diversity, the mean number of alleles per locus (A/L) was calculated: it is 3.83 for KG, and 2.91 for ŠG, while the mean number of genotypes per locus (G/L) was 5.16 for KG and 3.58 for ŠG. The results confirm the assumption that the number of possible classes with genotypes is higher than with alleles. The differences are the most conspicuous if the differences are observed in the occurrence of the individual alleles and the allele frequencies. The mean real hetero-zygote property of the clones in KG plantation is 0.2833, while the same value in ŠG is 0.3166. The mean theoretical hetero/zygote property of KG plantation is 0.3366, and of ŠG plantation it is 0.3491. The present differences show a deviation of the real status from the status of genetic balance according to the Hardy/Weinberg law. The results show that the use of the seed produced in the multiclone seed plantation, which originates from the clones from different provenances, may increase the risk of introducing undesired alleles into the natural population. A more acceptable solution would therefore be the seed plantations from the clones of a single population, and the use of their seed for the regeneration of this population

Strain Analysis of a Chiral Smectic A Elastomer

We present a detailed analysis of the molecular packing of a strained liquid crystal elastomer composed of chiral mesogens in the smectic A phase. X-ray diffraction patterns of the elastomer collected over a range of orientations with respect to the X-ray beam were used to reconstruct the three-dimensional scattering intensity as a function of tensile strain. For the first time, we show that the smectic domain order is preserved in these strained elastomers. Changes in the intensity within a given scattering plane are due to reorientation, and not loss, of the molecular order in directions orthogonal to the applied strain. Incorporating the physical parameters of the elastomer, a nonlinear elastic model is presented to describe the rotation of the smectic-layered domains under strain, thus providing a fundamental analysis to the mechanical response of these unique materials.Comment: 28 Page

Towards the dynamic conservation of Serbian spruce (Picea omorika) western populations

Key message High levels of genetic diversity, pronounced genetic structure and limitations to gene flow in Serbian spruce, a rare and endangered tree species from the refugial Balkan region, point towards a "one population-one unit" strategy for assembling a network of Genetic Conservation Units (GCUs) for its dynamic conservation. On the other hand, genetic information also permits to prioritize populations for conservation based on their contribution to genetic diversity and differentiation. Context Serbian spruce, Picea omorika (Panc.) Purk., is a rare, IUCN red-listed European conifer endemic to the Balkan region. Its current rigid conservation (without any intervention allowed in similar to 30 remnant populations) and the extant network of Genetic Conservation Units (four natural populations and three planted stands from the western part of the species range, in the Republic of Srpska, Bosnia and Herzegovina, RS-BH) might be ineffective in preserving the species' genetic diversity. Aims To facilitate implementation of dynamic conservation of Serbian spruce by re-assessing the number and size of remnant populations in RS-BH and updating genetic knowledge on these understudied western Serbian spruce populations. Methods Comprehensive field survey in RS-BH, genotyping 689 individuals from 14 western populations with ten highly informative nuclear EST-SSRs and analytical methods for prioritizing populations for conservation based on their contribution to the geographical structuring of genetic diversity. Results The genetic diversity of western Serbian spruce populations (Ae = 2.524, H-E = 0.451) is comparable with what was found for eastern ones; they are highly genetically differentiated (Hedrick's G'(ST) = 0.186; Jost's D = 0.097) and comprise ten distinct gene pools. Effective population size is often gt = 15. As much as 14% of alleles is not preserved in the extant GCUs established in natural populations. Eight populations positively contribute to within-population genetic diversity, four to genetic differentiation, and two are globally important in terms of diversity and differentiation. Although wildfires may contribute to admixture of different gene pools, re-establishment from seeds from extirpated populations has likely prevailed in studied populations. Conclusions A larger network of GCUs is required for the dynamic conservation of western Serbian spruce populations. A "one population-one unit" strategy, with 14 GCUs, would represent the safest approach to conserve species extant genetic variation in this part of the species range. Nonetheless, a strategy to prioritize populations for conservation based on their contribution to allelic diversity has been put forward. Given the rapid global warming and peculiarities of Serbian spruce distribution, habitat and life history traits, conservation measures based on a rigorously designed GCU network are urgent for its rescue and survival

Local adaptations to frost in marginal and central populations of the dominant forest tree Fagus sylvatica L. as affected by temperature and extreme drought in common garden experiments

Local adaptations to environmental conditions are of high ecological importance as they determine distribution ranges and likely affect species responses to climate change. Increased environmental stress (warming, extreme drought) due to climate change in combination with decreased genetic mixing due to isolation may lead to stronger local adaptations of geographically marginal than central populations. We experimentally observed local adaptations of three marginal and four central populations of Fagus sylvaticaL., the dominant native forest tree, to frost over winter and in spring (late frost). We determined frost hardiness of buds and roots by the relative electrolyte leakage in two common garden experiments. The experiment at the cold site included a continuous warming treatment; the experiment at the warm site included a preceding summer drought manipulation. In both experiments, we found evidence for local adaptation to frost, with stronger signs of local adaptation in marginal populations. Winter frost killed many of the potted individuals at the cold site, with higher survival in the warming treatment and in those populations originating from colder environments. However, we found no difference in winter frost tolerance of buds among populations, implying that bud survival was not the main cue for mortality. Bud late frost tolerance in April differed between populations at the warm site, mainly because of phenological differences in bud break. Increased spring frost tolerance of plants which had experienced drought stress in the preceding summer could also be explained by shifts in phenology. Stronger local adaptations to climate in geographically marginal than central populations imply the potential for adaptation to climate at range edges. In times of climate change, however, it needs to be tested whether locally adapted populations at range margins can successfully adapt further to changing conditions

The Analysis of Genetic Variability of Norway Spruce (Picea abies (L.) Karst.) Subpopulation at the Igman Mountain

Uporabom 12 izoenzimskih sustava, te analizom 20 gen lokusa, uspoređivana je genetička struktura dviju subpopulacija s planine Igman. Prema ekološkim pokazateljima, a misli se na klimu i njeno djelovanje, postoje razlike između subpopulacija, jer jedna pripada mrazištu a druga tipičnoj planinskoj klimi. Rezultati analize izoenzimskih biljega upućuju na postojanje razlika između analiziranih subpopulacija.In this study we analyzed the genetic structure of two autochthonous subpopulations of Norway spruce in the Mountain of Igman by usage of isoenzyme markers. We collected the material for the analysis in two separate plant communities. The subpopulation Igman – A is represented by fir-tree and spruce forest with randomly distributed white pine trees (Abieti-Piceetum illyricum Stef. 1960) while the Igman – B subpopulation is represented through the spruce tree of frosty type in the mountain area (Piceetum montanum s.lat. (Fuk. et Stef., 1958, emend. Horv. et al., 1974)). Between the subpopulations there is a 150 m difference in altitude. We analyzed the following systems of Acotinase (Aco-A), Glutamate dehydrogenase (Gdh-A), Glutamate oxaloacetate transaminase (Got-A, Got-B, Got-C), Izocitrate dehidrogenase (Idh-A, Idh-B), Leucine aminopeptidase (Lap-B), Malate dehydrogenase (Mdh-A, Mdh-B, Mdh-C), Menadione reductase (Mnr-A, Mnr-C), Phosphoglucose isomerase (Pgi-B), Phosphoglucomutase (Pgm-A), Shikimate dehydrogenase (Skdh-A), 6-Phosphogluconate dehydrogenase (6-Pgdh-A, 6-Pgdh-B, 6-Pgdh-C) and Fluorescentesterase (Fest-B). The frequency of the allele and the frequency of genotypes show diversity between subpopulations. The Allele differentiation was most evident at loci Got-C, 6-Pgdh-A. In the sample of the Igman – A subpopulation the frequency of the allele Aco-A2 was 7 % lower, and the frequency of 6-Pgdh-A2 7 % higher than in the sample from Igman – B subpopulation. The genotype subpopulations are most explicitly differentiated at loci Fest-B, Got-C, Lap-B, Mdh-C, Mnr-A, Mnr-C, Pgi-B, 6-Pgdh-A, 6-Pgdh-B, 6-Pgdh-C. If the Igman – A subpopulation is compared with Igman – B subpopulation, we have 8–14% higher frequency of homozygote: Got-C44 (52 % vs. 44 %), Fest22 (90 % vs. 80 %), Mnr-A22 (12 % vs. 4 %), Mnr-C22 (94 % vs. 82 %), 6-Pgdh-A22 (94 % vs. 80 %), 6-Pgdh-C22 (42 % vs. 30 %) and from 10–14 % higher heterozygote frequency for gene loci: Lap-B46 (12 % vs. 0 %), Pgi-B23 (52 % vs. 42 %), 6-Pgdh-B25 (54 % vs. 40 %). In Igman – B subpopulation versus Igman – A subpopulation has 10 % higher homozygote frequency, as follows: Pgi-B33 (46 % vs. 36 %), 6-Pgdh-B22 (50 % vs. 40 %) and between 8–14 % heterozygote frequency Fest-B12 (14 % vs. 2 %), Mnr-A24 (70 % vs. 56 %), Mnr-C23 (16 % vs. 4 %), 6-Pgdh-A23 (12 % vs. 4 %), 6-Pgdh-C25 (60 % vs. 46 %). By statistical calculation we obtained an average number of allele per locus, thus in the subpopulation A the number of allele per locus was 2,71, and the effective was 1,307, and in the subpopulation B it was 2,59, while the effective number was 1,332. The actual heterozygosis in subpopulation A was 24,4 %, and expected was 84,1 %, and in the subpopulation B the actual was 26,2 %, and expected 81,9 %. The number of polymorphous loci in both populations was 17, and the percentage of polymorphous loci was 85,00%. Through the analysis of the allele genetic closeness and genetic distance (d0), we can conclude that the closeness is very high, and differences are relatively small. Thus we determined that the allele closeness has the value of 0,959, and the distance is 0,041 according to Gregorius (1974), which in our case is an extremely high value taking into account the distance between subpopulations of approximately 2 km. Applied statistical parameters for comparison of populations did not show major differences, but the analysis of the direct comparison of the allele presence and their frequency points at the existence of differences, that is, the influence of diverse selection pressures at populations