The first known use of vermillion

Vermillion has been shown to be useful in preserving human bones from 5000 years ago. Remarkably well-preserved human bones have been found in the dolmenic burial La Velilla in Osorno (Palencia, Spain), carefully covered by pulverized cinnabar (vermillion) which ensured their preservation even in non-favorable climatic conditions. We believe the red powder was deliberately deposited for preservative use because no cinnabar mine is to be found within 160 km, because of the large amount (hundreds of kilograms) used, and because its composition, red mercuric sulphide, is similar to that of preparations used in technical embalming. This finding pushes back the data of the use of mercury ore for preservation by four millennia in South America, and by at least one millennium in the Old World. Chemical and thermal analyses of vermillion in La Velilla have demonstrated its great purity and shown that the cinnabar was pulverized and washed (but not heated), producing a bright red-orange tone.     

Fibronectin peptide DRVPHSRNSIT and fibronectin receptor peptide DLYYLMDL arrest gastrulation ofRana pipiens

Gastrulation is characterized by dramatic cell migration which is thought to require the interaction of cell adhesion molecules with extracellular molecules. We have tested two novel peptides, a fibronectin peptide and a fibronectin receptor peptide, for their effects on gastrulation of the leopard frogRana pipiens. The fibronectin peptide DRVPHSRNSIT corresponds to residues 1373–1383 of the cell-binding domain of fibronectin; the receptor peptide DLYYLMDL corresponds to residues 124–131 of 1 subunit of a variety of integrins including 51. Either of these peptides significantly inhibited gastrulation after being microinjected into mid-blastulae. These results indicate that these sequences may correspond to the ligand/receptor interaction sites of fibronectin and its receptor(s).     

基于新型相似日选取和VMD-NGO-BiGRU的短期光伏功率预测

光伏功率预测在现代电力系统调度和运行中起着重要作用.针对光伏发电功率的多变性和复杂性,提出了一种基于新型相似日选取和北方苍鹰算法（Northern Goshawk Optimization, NGO）优化双向门控循环单元（Bidirectional Gated Recurrent Unit, BiGRU）的短期光伏功率预测方法.首先,利用斯皮尔曼相关系数选取主要气象因子,通过变分模态分解（Variational Mode Decomposition, VMD）将原始光伏功率和最大气象因子分解重构为一系列子信号.其次,通过构建新的评价指标筛选出相似日数据集,利用一组BiGRU建立以相似日子信号为网络输入的深度学习模型,并利用NGO对每个BiGRU网络的超参数进行有效优化.最后,对各子信号的预测结果进行综合,得到最终的光伏功率预测值.仿真结果表明,所提混合深度学习方法在预测精度和计算效率方面均优于其他方法.     

Fe3Al合金的高温变形行为

用载荷松弛法对Ｆｅ－２８Ａｌ－２Ｔｉ合金在较高温度下的变形行为进行了研究．测定了Ｆｅ－２８Ａｌ－２Ｔｉ合金在高温变形时的载荷松弛曲线、应力减小因子Ｙ及激活能值,并对试样进行了显微结构观察．结果表明,Ｆｅ－２８Ａｌ－２Ｔｉ合金的高温变形是一个亚晶界吸收位错,而且不断向大角晶界转变的过程．     

Symmetry perception in an insect

Symmetrical visual patterns have a salient status in human perception, as evinced by their prevalent occurrence in art, and also in animal perception, where they may be an indicator of phenotypic and genotypic quality. Symmetry perception has been demonstrated in humans, birds, dolphins and apes. Here we show that bees trained to discriminate bilaterally symmetrical from non-symmetrical patterns learn the task and transfer it appropriately to novel stimuli, thus demonstrating a capacity to detect and generalize symmetry or asymmetry. We conclude that bees, and possibly flower-visiting insects in general, can acquire a generalized preference towards symmetrical or, alternatively, asymmetrical patterns depending on experience, and that symmetry detection is preformed or can be learned as perceptual category by insects, because it can be extracted as an independent visual pattern feature. Bees show a predisposition for learning and generalized symmetry because, if trained to it, they choose it more frequently, come closer to and hover longer in front of the novel symmetrical stimuli than the bees trained for asymmetry do for the novel asymmetrical stimuli. Thus, even organisms with comparatively small nervous systems can generalize about symmetry, and favour symmetrical over asymmetrical patterns.     

Insect motion detectors matched to visual ecology

To detect motion, primates, birds and insects all use local detectors to correlate signals sampled at one location in the image with those sampled after a delay at adjacent locations. These detectors can adapt to high image velocities by shortening the delay. To investigate whether they use long delays for detecting low velocities, we compared motion-sensitive neurons in ten species of fast-flying insects, some of which encounter low velocities while hovering. Neurons of bee-flies and hawkmoths, which hover, are tuned to lower temporal frequencies than those of butterflies and bumblebees, which do not. Tuning to low frequencies indicates longer delays and extends sensitivity to lower velocities. Hoverflies retain fast temporal tuning but use their high spatial acuity for sensing low-velocity motion. Thus an unexpectedly wide range of spatio-temporal tuning matches motion detection to visual ecology.     

Molecular evidence for increased hematopoietic proliferation in the spleen of the b/b laboratory rat

The splenomegaly and the appearance of a significant number of CFU-E (erythroid colony-forming units) and BFU-E¹ (erythroid burst-forming units) in the Belgrade laboratory rat (b/b) spleen prompted us to analyse further the molecular evidence for increased hematopoietic proliferation in the b/b spleen. Messenger RNAs (mRNAs) specific for globins, proteins for iron transport and deposition and the band 3 protein were used in rat erythropoietic tissues as markers for proliferation and erythroid differentiation. In the b/b spleen, all mRNAs analysed display an erythroid-specific pattern of expression. This analysis also revealed an enhanced level of mRNA for ferritin in the +/b spleen, whereas erythrocyte-specific mRNA production was normal.     

Antiviral activities of anthraquinones,bianthrones and hypericin derivatives from lichens

The antiviral activities of some naturally occurring anthraquinones bianthrones, and hypericin derivatives were compared by the end-point CPE (viral cytopathic effects) method and plaque assays. Under optimal conditions of exposure to light, hypericin, 7,7-dichlorohypericin and 5,7-dichloroemodin exhibited strong inhibitory activity against HSV-1 (herpes simplex virus type 1) in both assays. Partial inactivation of the virus was shown by emodin, 7-chloroemodin and 7-chloro-1-O-methylemodin; the bianthrones and other anthraquinones were found to be inactive. Antiviral activity appeared to be, positively correlated with increasing substitution of chlorine in the anthraquinone structure. In the absence of light, only hypericin and 7,7-dichlorohypericin displayed detectable activity.     

Dissection of the pheromone-modulated flight of moths using single-pulse response as a template

The upwind flight of male moths to conspecific females is mediated by the chemical and structural characteristics of a pheromone plume. We describe the reaction of maleCadra cautella, the almond moth, to the interception of single pulses of sex pheromone, the smallest structural units of odour plumes. Following loss of a pheromone plume, males cast, that is fly a crosswind course without progressing upwind. The response of casting males to interception of a pulse of 0.25 s duration was, after a delay of 0.21±0.07 s, to turn and briefly fly straighter upwind, resulting in average net upwind displacements of 18 cm in a 50 cm s^–1 wind. Upwind progress in the single-pulse response was the result of steering more upwind and an increase in airspeed, although average ground speed remained unchanged. During the last third of the surge, males turned crosswind, returning to casting flight. These behavioural reactions to pheromone contact and loss support the phasic-tonic model of odour-modulated flight, in which an underlying tonic counterturning rhythm, expressed upon pheromone loss, is briefly overridden by phasic upwind surges, expressed upon interception of the pheromone filament. The surge portion of the cast-surge-cast response was diminished and more crosswind if individual pulses were shorter (0.02 s), probably due to sub-optimal contact with pheromone. The cast-surge-cast response to interception of a single 0.25 s pulse was used as a template to interpret the form of flight tracks in plumes of known structure. The template matched portions of flight tracks of males flying in plumes of low pheromone pulse frequency, thus reflecting the male's pattern of pulse encounter. In plumes ensuring a high frequency of pulse interception, only the upwind surge portion of the template was expressed, resulting in nearly straight upwind flight tracks. Similar nearly straight upwind flight tracks occurred in flights along plumes of low pulse frequency with large volume. Thus flight tracks of maleC. cautella to point sources of pheromone depend on both the frequency and the size of filaments encountered.     

2-Carboxyethylgermanium sesquioxide,a synthetic organogermanium compound,as an inducer of contrasuppressor T cells

2-Carboxyethylgermanium sesquioxide (Ge-132), a synthesized organogermanium compound with immunomodulaing activities, was shown to be an inducer of anti-suppressor T cells in normal mice. The suppressor cell activity of T6S cells, a clone of burn-induced CD8⁺ IL-4-producing suppressor T cells, was clearly inhibited when a mixed lymphocyte-tumor cell reaction of the clone was conducted with splenic mononuclear cells from mice treated orally with a 100 mg/kg dose of Ge-132. The activity of anti-suppressor cells was demonstrated in spleens of mice 2 days after treatment with Ge-132 and reached its peak on day 3. The anti-suppressor cells induced by the compound were of a contrasuppressor T cell-linage, because they were characterized as CD4⁺ CD28⁺ TCR/⁺ Vicia villosa lectin-adherent T cells. These cells produced IFN- but did not produce IL-2, IL-4, IL-6 or IL-10 in their culture fluids. CD4⁺ anti-suppressor T cells induced by Ge-132 may be different from other subsets of CD4⁺ T cells because Th1 and Th2 cells generated in our laboratory did not adhere toVicia villosa lectin-coated petri dishes, and each produced specific cytokines. Th1 cells produced IFN- and IL-2 while Th2 cells produce IL-4 and IL-10 in vitro. These results suggest that Ge-132 may be useful as an inducer of contrasuppressor T cells in immunocompromised individuals bearing suppressor T cells. To eliminate suppressor T cells from immunocompromised hosts may result in improved resistance from various opportunistic infections.