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31.
Persons have different value preferences. Neuroimaging studies where value-based decisions in actual conflict situations were investigated suggest an important role of prefrontal and cingulate brain regions. General preferences, however, reflect a superordinate moral concept independent of actual situations as proposed in psychological and socioeconomic research. Here, the specific brain response would be influenced by abstract value systems and moral concepts. The neurobiological mechanisms underlying such responses are largely unknown. Using functional magnetic resonance imaging (fMRI) with a forced-choice paradigm on word pairs representing abstract values, we show that the brain handles such decisions depending on the person's superordinate moral concept. Persons with a predominant collectivistic (altruistic) value system applied a "balancing and weighing" strategy, recruiting brain regions of rostral inferior and intraparietal, and midcingulate and frontal cortex. Conversely, subjects with mainly individualistic (egocentric) value preferences applied a "fight-and-flight" strategy by recruiting the left amygdala. Finally, if subjects experience a value conflict when rejecting an alternative congruent to their own predominant value preference, comparable brain regions are activated as found in actual moral dilemma situations, i.e., midcingulate and dorsolateral prefrontal cortex. Our results demonstrate that superordinate moral concepts influence the strategy and the neural mechanisms in decision processes, independent of actual situations, showing that decisions are based on general neural principles. These findings provide a novel perspective to future sociological and economic research as well as to the analysis of social relations by focusing on abstract value systems as triggers of specific brain responses. 相似文献
32.
Oligopeptides having the general formula N-carbobenzoxy(γ-methyl-L -glutamyl)n-dimethyl-L -glutamate (with n = 1, 3, 5, 7, 11) were prepared, using both solid-phase synthesis and conventional peptide couplings in solution. The appearance of an ordered structure with increasing chain length was studied in organic solvents and at the air–water interface. The results obtained by thin-layer chromatography were interpreted. All the studies have demonstrated a very similar behaviour of this type of oligopeptide in solution and in monolayers. 相似文献
33.
34.
以普通小麦品种‘轮选988’为材料,采用溶液培养法,研究了根施不同浓度甜菜碱(1.0、2.0、3.0、4.0、5.0、10.0、15.0、20.0mmol·L~(-1))对镍(100μmol·L~(-1) NiSO_4)胁迫下小麦根系生长的影响,以及4.0mmol·L~(-1)甜菜碱处理镍胁迫幼苗根系相关抗逆生理生化指标的变化。结果表明:(1)与不施加镍对照相比,镍胁迫下小麦幼苗的根长、株高、鲜重和干重分别显著降低了14.7%、11.7%、15.0%和16.7%。(2)与单独镍胁迫处理相比,小麦幼苗的根长、株高、鲜重和干重均随着根施甜菜碱的浓度逐渐增加且呈先升后降的趋势,并以4.0mmol·L~(-1)外源甜菜碱处理效果较佳。(3)与单独镍胁迫处理相比较,在4.0mmol·L~(-1)外源甜菜碱处理下,小麦幼苗根系超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)和抗坏血酸过氧化物酶(APX)活性分别升高了284.7%、40.3%、82.9%和20.4%,超氧阴离子自由基(O-·2)含量、过氧化氢(H_2O_2)含量和丙二醛(MDA)含量分别显著降低了50.6%、38.4%和40.6%,可溶性糖含量及游离脯氨酸(Pro)含量分别显著降低了19.2%、45.4%,而根系活力大幅上升了358.0%。研究认为,根施适宜浓度外源甜菜碱可显著增强小麦幼苗根系的抗氧化能力,恢复根系活力,从而有效减弱镍胁迫对小麦幼苗生长的伤害。 相似文献
35.
Michelle Janssens Jeroen van Smeden Gert S. Gooris Wim Bras Guiseppe Portale Peter J. Caspers Rob J. Vreeken Thomas Hankemeier Sanja Kezic Ron Wolterbeek Adriana P. Lavrijsen Joke A. Bouwstra 《Journal of lipid research》2012,53(12):2755-2766
A hallmark of atopic eczema (AE) is skin barrier dysfunction. Lipids in the stratum corneum (SC), primarily ceramides, fatty acids, and cholesterol, are crucial for the barrier function, but their role in relation to AE is indistinct. Filaggrin is an epithelial barrier protein with a central role in the pathogenesis of AE. Nevertheless, the precise causes of AE-associated barrier dysfunction are largely unknown. In this study, a comprehensive analysis of ceramide composition and lipid organization in nonlesional SC of AE patients and control subjects was performed by means of mass spectrometry, infrared spectroscopy, and X-ray diffraction. In addition, the skin barrier and clinical state of the disease were examined. The level of ceramides with an extreme short chain length is drastically increased in SC of AE patients, which leads to an aberrant lipid organization and a decreased skin barrier function. Changes in SC lipid properties correlate with disease severity but are independent of filaggrin mutations. We demonstrate for the first time that changes in ceramide chain length and lipid organization are directly correlated with the skin barrier defects in nonlesional skin of AE patients. We envisage that these insights will provide a new therapeutic entry in therapy and prevention of AE. 相似文献
36.
Functional neuroimaging studies of decision-making so far mainly focused on decisions under uncertainty or negotiation with other persons. Dual process theory assumes that, in such situations, decision making relies on either a rapid intuitive, automated or a slower rational processing system. However, it still remains elusive how personality factors or professional requirements might modulate the decision process and the underlying neural mechanisms. Since decision making is a key task of managers, we hypothesized that managers, facing higher pressure for frequent and rapid decisions than non-managers, prefer the heuristic, automated decision strategy in contrast to non-managers. Such different strategies may, in turn, rely on different neural systems. We tested managers and non-managers in a functional magnetic resonance imaging study using a forced-choice paradigm on word-pairs. Managers showed subcortical activation in the head of the caudate nucleus, and reduced hemodynamic response within the cortex. In contrast, non-managers revealed the opposite pattern. With the head of the caudate nucleus being an initiating component for process automation, these results supported the initial hypothesis, hinting at automation during decisions in managers. More generally, the findings reveal how different professional requirements might modulate cognitive decision processing. 相似文献
37.
犬MC1R基因T105A基因座多态性及 与毛色性状相关性的研究The 总被引:4,自引:2,他引:2
为了检测犬MC1R基因T105A基因座的多态性,并分析该多态性与犬毛色表型的相关性,抽取111只外科手术学实验用杂种犬血液并提取DNA,记录毛色表型。采用PCR-RFLP技术,对MC1R基因T105A基因座进行基因多态性分析,并对该基因座DNA进行克隆测序;用二元变量相关分析的统计学方法分析基因座多态性与毛色性状之间的相关性。经PCR-RFLP分析结果表明,T105A基因座序列具有多态性,表现为A、B二个等位基因和AA、AB及BB 3种基因型。A、B等位基因频率分别为72.97%和27.03%,基因杂合度(H)为0.39。基因型AA频率为55.86%,BB为9.91%,AB为34.23%。对T105A多态性片段DNA克隆测序后发现,MC1R基因在编码第105位氨基酸的密码子第一个碱基存在由G到A的单碱基突变,该突变导致第105位氨基酸发生由丙氨酸向苏氨酸的改变。统计分析结果表明MC1R基因T105A基因座的多态性与毛色性状不存在显著的相关性,这可能是由于外科手术学实验用犬是杂种犬,其遗传背景不同所致,尚须在纯种犬群体中进一步研究MC1R基因对毛色的影响。
Abstract: In order to detect the polymorphism of T105A in MC1R gene in dogs and to analyze the relationship between the genetic polymorphisms and phenotypes of dog coat color, the blood samples of 111 cross-breed dogs were taken and their genomic DNAs were extracted. The phenotypes of dog coat color were recorded. The T105A locus of MC1R gene in the canine was detected through the technology of PCR-RFLP. Furthermore, the polymorphic fragments at T105A were sequenced. The relationships between the polymorphism of T105A and coat color trait were analyzed by the statistical methods of bivarate correlation analysis. By the method of PCR-RFLP, the T105A polymorphism was found with two alleles A and B and three genotypes AA, AB and BB. The frequencies of two alleles were 72.97% and 27.03%, respectively. The heterozygosity of T105A locus was 0.39. The frequencies of three genotypes were 55.86%, 34.23% and 9.91%, respectively. According to the results of sequencing, one base change from G to A at the position 105 was found at T105A locus and it altered amino acid at the position 105 from alanine to threonine. According to the statistical analysis, no significant association between the polymorphism of MC1R gene and the coat color was found and the result may be due to the differences of genetic background. Further research on MC1R gene should be done in pure breed dogs. 相似文献
38.
Henriette Selck John Aufderheide Nadine Pounds Charles Staples Norbert Caspers Valery Forbes 《Invertebrate Biology》2006,125(2):106-116
Abstract. The present experiments are part of a larger study designed to investigate the influence of husbandry parameters on the life history of the ramshorn snail, Marisa cornuarietis, in order to identify suitable husbandry conditions for maintaining multi‐generation populations in the laboratory for use in ecotoxicological testing. In this paper we focus on the effects of a combination of food types and feeding frequencies (i.e., the frequency with which the snails were offered food) on juvenile growth and survival at different temperatures. Offspring produced in the laboratory by wild specimens of M. cornuarietis, from Puerto Rico, were used to test the effects of three types of food (lettuce, alginate with fish food, alginate with snail mix) fed at three frequencies (given ad libitum on 4/4, 2/4, or 1/4 d) on juvenile survival and growth. The 4‐d feeding regimens were repeated four times, giving a total of 16 d for the experiments. The experiments were conducted at two temperatures (22° and 25°C) under a 12 h light:12 h dark photoperiod. Juvenile growth rates increased with increasing feeding frequency for all food types. The most rapid growth rates occurred in the high‐frequency lettuce treatments and the slowest growth rates in the low‐frequency lettuce and alginate with snail mix treatments. Juvenile snails grew faster at 25° than at 22°C, and mortality was about twice as high at the lower temperature. Growth rates were used to provide a rough estimate of time to maturity, which was determined to take about twice as long at 22° than at 25°C. The results showed that lettuce is the best food if supplied in abundance, but effects on growth are very dependent on feeding frequency and temperature. We conclude that 25°C is a more appropriate temperature for maintaining populations than 22°C, that lettuce provides a suitable food source, and that food should be supplied continuously for husbandry and toxicity testing of populations of M. cornuarietis. 相似文献
39.
Hubert Caspers 《Helgoland Marine Research》1968,17(1-4):422-434
Zusammenfassung 1. Der Zustrom von organischem Restmaterial aus den Flüssen in das Meer stellt eine Art von Verschmutzung dar mit der Folge einer Erhöhung des Trophiespiegels. Der Umfang der Verdünnung im Vorfluter und allgemein die geographischen und hydrographischen Situationen bestimmen das aus dem Angebot an Nährstoffen resultierende marine Equilibrium.2. Im Elbe-Aestuar haben wir alle Übergänge zwischen mixo-oligohalinen und -polyhalinen Zonen, deren Lage in den Jahreszeiten und zum Teil kurzfristig stark verschoben werden kann. Dadurch ergeben sich für das Benthos extrem astatische Verhältnisse.3. Durch den Tidewechsel wird das Plankton in den einzelnen Halinitätsbereichen länger zurückgehalten als in einem einseitig abfließenden Strom. Entsprechend dieser verlängerten Verweilzeit können sich typische Plankton-Biocoenosen in regionaler Sukzession ausbilden. Das Phytoplankton mit seiner schnellen Reproduktionsrate ist hierbei besonders begünstigt.4. Aus hydrographischen Gründen entsteht im oligo- bis mesohalinen Bereich eine Trübungszone, deren Material vornehmlich aus den Resten der limnischen Produktion (und Tonmineralien) besteht. Durch die natürlichen Gegebenheiten ist ein Aestuar-System sozusagen auf eine gesteigerte Dekompositionsleistung eingestellt, so daß eine anthropogene Zugabe von organischem Restmaterial ohne stärkere Beeinträchtigung des biocoenotischen Systems möglich ist.5. Im Vormündungsgebiet der Elbe bewirkt der Einstrom großer Mengen gelöster Nährstoffe aus dem Aestuar eine Erhöhung des trophischen Niveaus und eine Sekundärverschmutzung, deren Auffangzonen die tieferen Meeresflächen und die Wattenbereiche darstellen. Die Watten sind biocoenotisch auf die Aufnahme großer Mengen an Detritusmaterial eingestellt; es wird die Frage diskutiert, wieweit in solche Bereiche auch eine zusätzliche Einleitung von organischem Abwasser ohne wesentliche Beeinträchtigung des biologischen Equilibriums möglich ist.
Mit Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献
Influence of the elbe on the pollution of the north sea
The inflow of organic rest material from rivers into the sea represents a kind of pollution resulting in an increased trophic level. Dilution in the river as well as the general geographic and hydrographic situations determine the marine equilibrium resulting from the supply of nutrients. In the Elbe estuary exist all kinds of transitions between mixo-oligohaline and mixo-polyhaline zones; the location of which may shift over decades or, in part, over short periods of time. As a consequence, the benthos is exposed to extreme variations. Due to the alternation of tides, the plankton remains longer within the individual salinity zones than would be the case in a one directional flow system. Hence typical planktonic biocoenoses can develop in regional successions. In this regard the phytoplankton with its fast reproduction rates is especially favoured. Due to hydrographical reasons a turbidity zone is formed in the oligoto merohaline areas containing primarily remains of the limnic production. An estuary system is, by its nature, adjusted to accept increased decomposition loads; addition of organic anthropogenic remains is, therefore, tolerable without significant biocoenotic consequences. The inflow of dissolved nutrients from the Elbe results in an increase of the trophic niveau and a secondary pollution in the outer regions of the estuary. Mud flats and deeper sea areas are capable of accepting large amounts of detritus. The question, to what extent these areas may be capable of tolerating additional organic waste products without negative biological consequences, is discussed.
Mit Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献
40.
Data for the historical years 1970 and 1995 and the FAO-Agriculture Towards 2030 projection are used to calculate N inputs (N fertilizer, animal manure, biological N fixation and atmospheric deposition) and the N export from the field in harvested crops and grass and grass consumption by grazing animals. In most industrialized countries we see a gradual increase of the overall N recovery of the intensive agricultural production systems over the whole 1970-2030 period. In contrast, low N input systems in many developing countries sustained low crop yields for many years but at the cost of soil fertility by depleting soil nutrient pools. In most developing countries the N recovery will increase in the coming decades by increasing efficiencies of N use in both crop and livestock production systems. The surface balance surplus of N is lost from the agricultural system via different pathways, including NH3 volatilization, denitrification, N2O and NO emissions, and nitrate leaching from the root zone. Global NH3-N emissions from fertilizer and animal manure application and stored manure increased from 18 to 34 Tg·yr-1 between 1970 and 1995, and will further increase to 44 Tg·yr-1 in 2030. Similar developments are seen for N2O-N (2.0 Tg·yr-1 in 1970, 2.7 Tg·yr-1 in 1995 and 3.5 Tg·yr-1 in 2030) and NO-N emissions (1.1 Tg·yr-1 in 1970, 1.5Tg·yr-1 in 1995 and 2.0 Tg·yr-1 in 2030). 相似文献