994 resultados para Gaucelm Faidit, fl. 1156-1209.


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Mr=300.33 , triclinic, P1, a=5.635 (2), b=11.077(2), c=11.582(2)A, a= 70.48 (1), fl= 88.16 (3), y=80.56(3) ° , V= 670.325 A3, Z=2, D x = 1.49 Mg m -3, Cu Ka, n= 1.54184 ,A, g = 2.308mm -1, F(000)=316, T=301K, R=0.054, R w = 0.093 for 1944 observed counter reflections. The sulphur position with respect to the dihydrouracil ring, which is of possible relevance to the action of thymidylate synthetase, is axial in molecule A and equatorial in B. Both molecules show the anti conformation about the glycosidic bond [torsion angle C(6)-N(1)-C(1')-O(4'), 2'CN = 21.6 (9) and 29.4 (10) °] and have the C(4')-endo, O(4')-exo (40T) sugar conformation. The dioxolane-ring conformation is O(2')-endo in A and C(7)-endo in B. The dihydrouracil rings show self base pairing with hydrogen bondsN(3A)...O(ZB) and N(3B)...O(ZA).

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Mr = 248, monoclinic, P21/n, a = 12.028 (2), b=7.168(2), c= 15.187(5)A, fl=91.88(2) °, Z= 4, V= 1308.6,~3, Din= 1.26, Dx= 1.263 Mgm -3, 2 (Cu Ka) = 1.5418 .A, g = 0.86 mm -1, F(000) = 536, T= 293 K. Final R = 5.6% for 2120 observed reflexions. Owing to the push-pull effect, the C=C bond distance is as long as 1.464 (2)/k with the twist angle about the bond 62.6.

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(I): Mr= 168, triclinic, P1, Z=2, a= 5.596 (2), b = 6.938 (3), c = 10.852 (4) A, ~t= 75.64 (3), fl= 93.44 (3), ),= 95.47 (3) °, V= 406.0A 3, Din= 1.35 (by flotation using carbon tetrachloride and n-hexane), D x= 1.374 Mg m -3, g(Mo Kct, 2 = 0.7107 A) = 1.08 cm -l, _F(000) = 180, T= 293 K. (II): Mr= 250, triclinic, P1, Z= 2, a = 7.731(2), b=8.580(2), c=11.033(3)A, a= 97-66 (2), fl= 98.86 (2), y= 101.78 (2) °, V= 697.5 A 3, D m = 1.18 (by flotation using KI solution), Dx= 1.190Mgm -3, g(MoKa, 2=0.7107A)= 1.02 cm -1, F(000) = 272, T= 293 K. Both structures were solved by direct methods and refined to R = 4.4% for 901 reflexions for (I) and 5.7% for 2001 reflexions for (II). The C=C bond distances are 1.451 (3) A in (I) and 1.468 (3)A in (II), quite significantly longer than the C=C bond in ethylene [1.336 (2).~; Bartell, Roth, Hollowell, Kuchitsu & Young (1965). J. Chem. Phys. 42, 2683-2686]. The twist angle about the C=C bond in (II) is 72.9 (5) ° but molecule (I) is essentially planar, the twist angle being only 4.9 (5) ° .

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The attempt to refer meaningful reality as a whole to a unifying ultimate principle - the quest for the unity of Being - was one of the basic tendencies of Western philosophy from its beginnings in ancient Greece up to Hegel's absolute idealism. However, the different trends of contemporary philosophy tend to regard such a speculative metaphysical quest for unity as obsolete. This study addresses this contemporary situation on the basis of the work of Martin Heidegger (1889-1976). Its methodological framework is Heidegger's phenomenological and hermeneutical approach to the history of philosophy. It seeks to understand, in terms of the metaphysical quest for unity, Heidegger's contrast between the first (Greek) beginning or "onset" (Anfang) of philosophy and another onset of thinking. This other onset is a possibility inherent in the contemporary situation in which, according to Heidegger, the metaphysical tradition has developed to its utmost limits and thereby come to an end. Part I is a detailed interpretation of the surviving fragments of the Poem of Parmenides of Elea (fl. c. 500 BC), an outstanding representative of the first philosophical beginning in Heidegger's sense. It is argued that the Poem is not a simple denial of apparent plurality and difference ("mortal acceptances," doxai) in favor of an extreme monism. Parmenides' point is rather to show in what sense the different instances of Being can be reduced to an absolute level of truth or evidence (aletheia), which is the unity of Being as such (to eon). What in prephilosophical human experience is accepted as being is referred to the source of its acceptability: intelligibility as such, the simple and undifferentiated presence to thinking that ultimately excludes unpresence and otherness. Part II interprets selected key texts from different stages in Heidegger's thinking in terms of the unity of Being. It argues that one aspect of Heidegger's sustained and gradually deepening philosophical quest was to think the unity of Being as singularity, as the instantaneous, context-specific, and differential unity of a temporally meaningful situation. In Being and Time (1927) Heidegger articulates the temporal situatedness of the human awareness of meaningful presence. His later work moves on to study the situational correlation between presence and the human awareness. Heidegger's "postmetaphysical" articulation seeks to show how presence becomes meaningful precisely as situated, in an event of differentiation from a multidimensional context of unpresence. In resigning itself to this irreducibly complicated and singular character of meaningful presence, philosophy also faces its own historically situated finitude. This resignation is an essential feature of Heidegger's "other onset" of thinking.

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Game strategies have been developed in past decades and used in the field of economics, engineering, computer science and biology due to their efficiency in solving design optimisation problems. In addition, research on Multi-Objective (MO) and Multidisciplinary Design Optimisation (MDO) has focused on developing robust and efficient optimisation method to produce quality solutions with less computational time. In this paper, a new optimisation method Hybrid Game Strategy for MO problems is introduced and compared to CMA-ES based optimisation approach. Numerical results obtained from both optimisation methods are compared in terms of computational expense and model quality. The benefits of using Game-strategies are demonstrated.

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The crystal structures of (1) L-arginine D-asparate, C6HIsN40~.C4H6NO4 [triclinic, P1, a=5.239(1), b=9.544(1), c=14.064(2)A, a=85"58(1), /3=88.73 (1), ~/=84.35 (1) °, Z=2] and (2) L-arginine D-glutamate trihydrate, C6H15N40~-.CsHsNO4.3H20 [monoclinic, P2~, a=9.968(2), b=4.652(1), c=19.930 (2) A, fl = 101.20 (1) °, Z = 2] have been determined using direct methods. They have been refined to R =0.042 and 0.048 for 2829 and 2035 unique reflections respectively [I>2cr(I)]. The conformations of the two arginine molecules in the aspartate complex are different from those observed so far in the crystal structures of arginine, its salts and complexes. In both complexes, the molecules are organized into double layers stacked along the longest axis. The core of each double layer consists of two parallel sheets made up of main-chain atoms, each involving both types of molecules. The hydrogen bonds within each sheet and those that interconnect the two sheets give rise to EL-, DD- and DE-type head-to-tail sequences. Adjacent double layers in (1) are held together by side-chain-side-chain interactions whereas those in (2) are interconnected through an extensive network of water molecules which interact with sidechain guanidyl and carboxylate groups. The aggregation pattern observed in the two LD complexes is fundamentally different from that found in the corresponding EL complexes.

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This paper proposes a multilevel inverter which produces hexagonal voltage space vector structure in lower modulation region and a 12-sided polygonal space vector structure in the over-modulation region. Normal conventional multilevel inverter produces 6n +/- 1 (n=odd) harmonics in the phase voltage during over-modulation and in the extreme square wave mode operation. However, this inverter produces a 12-sided polygonal space vector location leading to the elimination of 6n 1 (n=odd) harmonics in over-modulation region extending to a final 12-step mode operation. The inverter consists of three conventional cascaded two level inverters with asymmetric dc bus voltages. The switching frequency of individual inverters is kept low throughout the modulation index. In the low speed region, hexagonal space phasor based PWM scheme and in the higher modulation region, 12-sided polygonal voltage space vector structure is used. Experimental results presented in this paper shows that the proposed converter is suitable for high power applications because of low harmonic distortion and low switching losses.

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Sommaren 1788 drabbades den svenska flottan av en svårartad febersjukdom. Febern, som senare definierats som febris recurrens el. återfallsfeber, hade sitt ursprung i den ryska flottan. Besättningen ombord skeppet Vladislav, krigsbytet från slaget vid Hogland, bar på ett stort antal smittade klädlöss. Efter flottans ankomst till Sveaborg spred sig sjukdomen snabbt bland manskapet, men även bland fästningens garnison. Förhållandena inom militären, både inom lantarmén och framför allt inom flottan, var gynnsamma för epidemiers spridning. De trånga utrymmena, den ensidiga kosten, det undermåliga dricksvattnet, den bristande hygienen: allt gynnade uppkomsten och spridningen av olika epidemier. Manskapets försämrade allmäntillstånd gjorde, att sjukdomarna blev mera förödande än vad de i andra förhållanden skulle ha varit. Bristen på manskap och material under Gustav III:s ryska krig var enormt, bl.a. var bristen på medicinsk personal och -utrustning skriande. Då flottan och armén drabbades av en epidemi av katastrofala dimensioner stod myndigheterna hjälplösa. Epidemin visaqr tydligt hur illa förberett hela kriget var och hur misskött flottans sjukvård var. På Sveaborg var förhållandena fruktansvärda. Halva garnisonen uppges ha avlidit, och det låg travar av lik överallt. Kaserner m.fl. byggnader adapterades till provisoriska lasarett och det rådde brist på allt. De medicinska myndigheterna representerades av den till fästningen skickade andra fältläkaren, som tillsammans med läkarna på fästningen gjorde sitt bästa i enlighet med tidens vårdmetoder. Då den svenska örlogsflottan i november seglat över tilll Karlskrona spred sig epidemin i staden. Sjukdomen grasserade också bland de civila. Då sjukdomens orsak och utbredningssätt var okända, kunde man varken hindra epidemin från att spridas eller genomföra adekvata vårdmetoder. Tvärtom, med de hemförlovade båtsmännen spred sig sjukdomen även till de övriga delarna av riket. Under 1789 var flottan p.g.a. de många sjukdomsfallen närmast operationsoduglig. Under vårvintern och våren 1790 avtog epidemin. Epidemin var ett svårt medicinskt problem. För att utreda situationen i Karlskrona skickade den tillförordnade regeringen, utredningskommissionen och Collegium medicum sina egna representanter till staden. De olika läkarnas sjukdomssyner grundade sig främst på tron om sjukdomars uppkomst genom miasma och förbättrandet av luftkvaliteten sågs som en väsentlig vårdform. I arbetet jämförs de olika myndigheternas och några av de på platsen varande läkarnas syn på sjukdomens art, dess orsaker och ursprung. De flesta härleder sjukdomen till den ryska flottan, och nämner någon form av smitta. Som främsta sjukdomsorsak nämns dock miasma och de rekommenderade vårdformerna representerade den humoralpatologiska synen. Förste amiralitetsläkaren Arvid Faxe representerar dock en annan åsikt, i det att han enbart tror på sjukdomens överföring via smitta. Epidemin var också ett politiskt problem. Epidemin var en lokal angelägenhet ända till dess att flottans operationer hämmades av manskapsbristen, varefter den blev ett ärende på högsta nivå. Kungen ingrep sommaren 1789 genom att grunda en kommision med rätt vidsträckta befogenheter. I Karlskrona verkar de militära myndigheterna och läkarna ha misstrott och skuldsatt varandra för katastrofen, och förhållandet mellan de till staden sända utredarna och militärerna var likaså inflammerat. Genom källorna återspeglas rivalitet, avund och inbördes konkurrens. Personalbristen var svår, och den skyldiga söktes utanför den egna kretsen. Den danskfödde apotekaren med sina påstott otjänliga mediciner blev en ypperlig syndabock. Örlogsflottan beräknas i sjukdomar ha förlorat omkring 10.000 man i döda, huvudsakligen i Karlskrona (civila inberäknade). Armén och Skärgårdsflottan uppges likadeles ha mist omkring 10.000 man, medan antalet i strid stupade armésoldater endast var ca 1500. Sammanlagt antas alltså ca 20.000 människor ha mist livet; både i återfallsfeber, men även i andra, samtidigt grasserande farsoter. I denna siffra är inte de övriga delarna av riket inberäknade. Epidemin i fråga kan alltså på goda grunder anses vara det svenska 1700-talets största medicinska katastrof.

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Lutjanus argentimaculatus is an Indo-Pacific species that inhabits riverine, coastal and offshore reef habitats. An investigation of the reproductive biology of Lutjanus argentimaculatus in northeastern Queensland waters (Australia) was undertaken between 1999 and 2002. Individuals in inshore estuarine and freshwater riverine habitats were mostly immature whereas those captured in offshore reef waters were predominantly mature. Males matured at a smaller size than females, with the length-at-50%-maturity (Lm50) for males estimated to be 470.7 mm fork length (FL) and 531.4 mm FL for females. The spawning season in northeastern Queensland was mostly during the austral spring-summer and peaked in December. The presence of ripe female fish and occurrence of postovulatory follicles in histological sections provided evidence that spawning activity was more pronounced during the full and third quarter moon phases. Lutjanus argentimaculatus were highly fecund with estimates of up to 4 x 106 ova per spawning event. Immature fish concentrated in inshore areas where they were targeted by recreational fishers whereas, in offshore areas, commercial fishers caught predominantly larger, mature fish.

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O-Acetylsalicylamide (Ia), C9H9NO3, M r =179.18, monoclinic, P2Jc, a=8.155(5), b=8.571 (2), c= 13.092 (3)A, fl=99.54 (5) ° , V= 902.4(6)A 3, Z=4, Dm=l.31, Dx=l.319gcm -3, 2(Mo Ka) = 0.71069 A,/~ = 1.08 cm -1, F(000) = 376, T = 295 K, R = 0.076 for 1604 reflections. O-Benzoylsalicylamide (Ib), C14HtlNO 3, M,=241.2, monoclinic, P2t/e, a=9.423(1), b=5.116(1), e= 26.424 (2) A, fl= 103.97 (1)% V= 1236.2 (3)/~3, Z= 4, D~ = 1.28, D x = 1.296 gcm -3, ,;L(Cu Ks) = 1.5418 A, p = 7.71 cm-', F(000) = 504, T= 295 K, R =0.050 for 2115 reflections. The dihedral angles between the amide group and the benzene ring are 39.9 ° (Ia) and 37.9 ° (Ib), whereas between the acyl group and the benzene ring they are 78.1 ° (Ia) and 93.4 ° (Ib). The differences in the packing of the two structures are brought out in terms of the observed hydrogen-bonding patterns. Based on the crystallographic results, an intramolecular mechanism for the migration of the acyl group from the O to the N position is suggested in both compounds.

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One of the pathways for transfer of cadmium (Cd) through the food chain is addition of urban wastewater solids (biosolids) to soil, and many countries have restrictions on biosolid use to minimize crop Cd contamination. The basis of these restrictions often lies in laboratory or glasshouse experimentation of soil-plant transfer of Cd, but these studies are confounded by artefacts from growing crops in controlled laboratory conditions. This study examined soil to plant (wheat grain) transfer of Cd under a wide range of field environments under typical agronomic conditions, and compared the solubility and bioavailability of Cd in biosolids to soluble Cd salts. Solubility of biosolid Cd (measured by examining Cd partitioning between soil and soil solution) was found to be equal to or greater than that of soluble Cd salts, possibly due to competing ions added with the biosolids. Conversely, bioavailability of Cd to wheat and transfer to grain was less than that of soluble Cd salts, possibly due to addition of Zn with the biosolids, causing reduced plant uptake or grain loading, or due to complexation of soluble Cd2+ by dissolved organic matter.

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Whilst the topic of soil salinity has received a substantive research effort over the years, the accurate measurement and interpretation of salinity tolerance data remain problematic. The tolerance of four perennial grass species (non-halophytes) to sodium chloride (NaCl) dominated salinity was determined in a free-flowing sand culture system. Although the salinity tolerance of non-halophytes is often represented by the threshold salinity model (bent-stick model), none of the species in the current study displayed any observable salinity threshold. Further, the observed yield decrease was not linear as suggested by the model. On re-examination of earlier datasets, we conclude that the threshold salinity model does not adequately describe the physiological processes limiting growth of non-halophytes in saline soils. Therefore, the use of the threshold salinity model is not recommended for non-halophytes, but rather, a model which more accurately reflects the physiological response observed in these saline soils, such as an exponential regression curve.

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C17H2602, M, = 262, triclinic, PI, a = 8.513(2), b = 8.970(2), c = 11.741(3)A, a = 120.51 (5), fl = 93.30(4), y = 68.43(4) ° , V = 708.9,/k 3, Z = 2, D O = 1.213, D e = 1.227 Mg m -a, g(Mo Ka, 2 = 0.7107 ,&) = 0.084 mm -1, F(000) = 288. The structure, solved by direct methods, has been refined to an R value of 5.9% using 1361 intensity measurements. The ring junctions, in sequence from either end of the polycycle, are cis, trans and cis.

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Remote drafting technology now available for sheep allows targeted supplementation of individuals within a grazing flock. This paper reports results of three experiments. Experiment 1 examined the weight change of Merino wethers allowed access to either lupin grain or whole cottonseed 0, 1, 2 or 7 days/week for 6 weeks. Experiment 2 examined the weight change of Merino wethers allowed access to either lupins or a sorghum + cottonseed meal (CSM) supplement 0, 2, 4 or 7 days/week for 8 weeks. Experiment 3 investigated the relationship between five allocations of trough space at the supplement self-feeders (5–50 cm/sheep) and the weight change of Merino wethers allowed access to lupins 1 day/week for 8 weeks. In all experiments, the Merino wethers had free access as a single group to drinking water and low quality hay in a large group pen and were allowed access to supplement once per day on their scheduled days of access. No water was available in the areas containing supplement, but one-way flow gates allowed animals to return to the group pen in their own time. There was a linear response in growth rate to increased frequency of access to lupins in Experiments 1 and 2, with each additional day of access increasing liveweight gain by 26 and 21 g/day, respectively. Similarly, the response to the sorghum + CSM supplement was linear, although significantly lower (P < 0.05), at 12 g/day. Providing access to whole cottonseed resulted in no significant change in growth rate compared with the control animals. In Experiment 3, decreasing trough space from 50 to 5 cm/sheep had no effect on sheep liveweight change. It was concluded that the relationships developed here, for growth response to increased frequency of access to lupins or a sorghum + CSM supplement, could be used to indicate the most appropriate frequency of access to supplement, through a remote drafting unit, to achieve sheep weight change targets. Also, that a trough space of 5 cm/sheep appears adequate in this supplementation system.

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Time-resolved resonance Raman spectroscopy (TR3) has been used to study the effect of solvent polarity on the mechanism and nature of intermediates formed in photoinduced electron-transfer reaction between triplet flouranil ((FL)-F-3) and tetramethylbenzene (TMB). Comparison of the TR3 spectra in polar, nonpolar, and medium polar media suggests that formation of radical anion due to electron-transfer reaction between (FL)-F-3 and TMB is favored in more polar solvents, whereas ketyl radical formation is more favored in less polar media. Compared to ketyl radical, the extent of radical anion formation is negligible in nonpolar solvents. Therefore, it is inferred that in nonpolar media ketyl radical is mainly generated by hydrogen-transfer reaction in the encounter complex between (FL)-F-3 and TMB. In solvents of medium polarity, the ion-pair decay leads to the formation of both ketyl radical and ketyl radical formed from the encounter between triplet state and the donor. Thus, competition between the formation of ketyl radical and ion pair is influenced by the solvent polarity. The nature of the ion pair in different solvent polarity has been investigated from the changes observed in the vibrational frequency of (fluoranil) FL part of the complex.