Scandium clusters in fullerene cages

The production and spectroscopic characterization of fullerene-encapsulated metal-atom clusters is reported. In particular, both solution and solid-state electron paramagnetic resonance (EPR) spectra of Sc(3)C(82) have been obtained. ScC(82) also gives an EPR spectrum, but Sc2Cn species-the most abundant metallofullerenes in the mass spectrum-are EPR-silent even though Sc(2) is EPR-active in a rare-gas matrix at 4.2 K. The results suggest that the three scandium atoms in Sc(3)C(82) form an equilateral triangle-as was previously suggested for Sc(3) molecules isolated in a cryogenic rare-gas matrix. The spectrum of ScC(82) has features similar to those found earlier for LaC(82) and YC(82), suggesting that it can also be described as a +3 metal cation within a -3 fullerene radical anion. An implication of this work is that production of macroscopic quantities of clustercontaining fullerenes may make possible the fabrication of exotic new structures with regular arrays of metal-atom clusters isolated in fullerene molecules, resulting in a new type of host/guest nanostructured material.     

Infrared spectroscopic evidence for protonated water clusters forming nanoscale cages

Size-dependent development of the hydrogen bond network structure in large sized clusters of protonated water, H+(H2O)n (n = 4 to 27), was probed by infrared spectroscopy of OH stretches. Spectral changes with cluster size demonstrate that the chain structures at small sizes (n less, similar 10) develop into two-dimensional net structures (approximately 10 < n < 21), and then into nanometer-scaled cages (n >/= 21).     

Flyblock test preparation for cows against bloodsucking insects

On the surface of cows’ bodies were detected horseflies Chrysops caecutiens, Chr. pictus, Tabanus bovinus, T. sudeticus; blood-sucking flies Hydrotaea irritans, Haematobia spp., Haematobosca stimulans, Stomoxys calcitrans; and flies with licking mouthparts—Musca autumnalis, Morrelia spp., Fannia canicularis, Musca domestica, Muscina stabulans. The amount of flies on animals in July and August varied: maximum in the first and second decade of July (average of 27–56), quite large amount in late July and early August (14–39), and minimum from mid-August until the first decade of September (3–8). The studies were conducted on 1167 cows and showed high efficacy of Flyblock against zoofilnymi flies, horseflies, and midges. A consecutive period of protective action was established: after 12–14 days, the protective effect coefficient was 97%; after 17–20 days, it was 86%; after 23–27 days, it was 78%; and after 30 days, it was 75%.     

鳞翅目昆虫人工饲养技术研究进展

鳞翅目昆虫的研究越来越受到人们关注,而人工饲养是昆虫研究的基础,尤其是昆虫人工饲料配方的研发.文章以现有相关文献为依据,从人工饲养技术研究、人工饲料配方的研制方法、饲养环境和饲养操作优化等方面总结鳞翅目昆虫人工饲养技术研究进展,发现鳞翅目昆虫人工饲养技术及饲料配方已取得较大进展,但现行研究主要以提高饲养昆虫的存活率为目的,而忽略昆虫的生理性状.因此,建议在优化人工饲养技术的同时,需连续和定期评估人工饲养的种群与野生种群的性能差异,为科学研究提供大量高质量的实验虫源.     

A novel target for antidiuretic hormone in insects

Diuresis in insects is controlled by two antagonistic hormone groups: diuretic hormones, which promote water loss, and antidiuretic hormones, which inhibit it. All known antidiuretic factors act solely to promote fluid reabsorption by the hindgut and do not affect secretion by the Malpighian tubules. In the house cricket, Acheta domesticus, an antidiuretic hormone was found that inhibits fluid secretion by the Malpighian tubules but has no effect on the hindgut. Correlations were found between the density of neurosecretory granules and the presence of antidiuretic hormone in the corpora cardiaca, suggesting that the hormone is released from specific axons. Its release is triggered by dehydration; the hormone is detectable in the hemolymph of water-deprived crickets. These results imply that an unusual mechanism regulates water balance in these insects.     

烤烟塑料托盘假植育苗的研究

为了提高烟苗的素质,在聚乙烯塑料托盘上,用猪粪渣、可沙、大田本土作为不同基础材料配方进行烤烟假植育苗的研究。结果表明,以50%猪粪渣加50%河沙处理的烟苗素质最佳,其次是50%猪粪渣加505大田本土的处理,这两种处理的烟苗素质均优于稻草圈假植苗,达到了壮苗标准。托盘假植苗的适栽苗龄为15～20d,移栽大田后,此稻草圈假植苗株有效叶数增加0.8片,产量增加5.0%,产值提高5.1%,育苗成本降低60%,纯收入增加8.2%。     

昆虫图像几何形状特征的提取技术研究

为进行昆虫图象的识别和分类，对昆虫图象几何形状特征的提取及测量进行了研究。提取了区域面积、边界周长、孔洞数、偏心率、形状参数、圆形性、似圆度、球状性和叶状性9个直观易测的特征。采用判别分析方法对这些特征进行筛选得到6个具有判别意义的特征，分别为区域面积、偏心率、形状参数、周长、似圆度、叶状性；剔除了与似圆度具有相关性的圆形性和球状性等特征。利用这6个特征对3种昆虫进行了识别，准确率均达到100％，表明本研究所提取的6个昆虫图象特征用于昆虫图象识别是有效的。     

我国食用昆虫研究、开发现状与发展前景

介绍了中国食用昆虫的历史及食虫习俗、食用昆虫种质资源,分析了食用昆虫产品开发的现状及影响其开发的因素,指出了开发食用昆虫资源的应对措施及食用昆虫在中国的发展前景。     

Thermoregulation in endothermic insects

On the basis of body weight, most flying insects have higher rates of metabolism, and hence heat production, than other animals. However, rapid rates of cooling because of small body size in most cases precludes appreciable endothermy. The body temperature of small flies in flight is probably close to ambient temperature, and that of flying butterflies and locusts is 5 degrees to 10 degrees C above ambient temperature. Many moths and bumblebees are insulated with scales and hair, and their metabolism during flight can cause the temperature of the flight muscles to increase 20 degrees to 30 degrees C above ambient temperature. Curiously, those insects which (because of size, insulation) retain the most heat in the thorax during flight, also require the highest muscle temperature in order to maintain sufficient power output to continue flight. The minimum muscle temperature for flight varies widely between different species, while the maximum temperature varies over the relatively narrow range of 40 degrees to 45 degrees C. As a consequence, those insects that necessarily generate high muscle temperatures during flight must maintain their thoracic temperature within a relatively narrow range during flight. Active heat loss from the thorax to the abdomen prevents overheating of the flight motor and allows some large moths to be active over a wide range of ambient temperatures. Bumblebees similarly transfer heat from the flight musculature into the abdomen while incubating their brood by abdominal contact. Many of the larger insects would remain grounded if they did not actively increase the temperature of their flight muscles prior to flight. Male tettigoniid grasshoppers elevate their thoracic temperature prior to singing. In addition, some of the social Hymenoptera activate the "flight" muscles specifically to produce heat not only prior to flight but also during nest temperature regulation. During this "shivering" the "flight" muscles are often activated in patterns different from those during flight. The muscles contract primarily against each other rather than on the wings. However, the rate of heat production during shivering and flight is primarily a function of the action potential frequency rather than of the patterns of activation. Thermoregulation is a key factor in the energetics of foraging of some of the flower-visiting insects. The higher their muscle temperature the more flowers they can visit per unit time. When food supplies are ample, bees may invest relatively large amounts of energy for thermoregulation. While shivering to maintain high body temperatures during the short intervals they are perched on flowers (as well as while in the nest), bumblebees often expend energy at rates similar to the rates of energy expenditure in flight. Unlike vertebrates, which usually regulate their body temperature at specific set points, the body temperature of insects is labile. It often appears to be maintained near the lower temperature at which the muscles are able to perform the function at hand. The insects' thermal adaptations may not differ as much from those of vertebrates as previously supposed when size, anatomy, and energy requirements are taken into account.     

Migration strategies of insects

Physiological and ecological results from a variety of species are consistent with what seem to be valid general statements concerning insect migration. These are as follows: (i)During migration locomotory functions are enhanced and vegetative functions such as feeding and reproduction are suppressed. (ii) Migration usually occurs prereproductively in the life of the adult insect (the oogenesis-flight syndrome). (iii)Since migrant individuals are usually prereproductive, their reproductive values, and hence colonizing abilities, are at or near maximum. (iv) Migrants usually reside in temporary habitats. (v)Migrants have a high potential for population increase, r, which is also advantageous for colonizers. (vi)Both the physiological and ecological parameters of migration are modifiable by environmental factors (that is, phenotypically modifiable)to suit the prevailing conditions. Taken together, these criteria establish a comprehensive theory and adumbrate the basic strategy for migrant insects. This basic strategy is modified to suit the ecological requirements of individual species. Comparative studies of these modifications are of considerable theoretical and practical interest, the more so since most economically important insects are migrants. No satisfactory general statements can as yet be made with respect to the genotype and migration. Certainly we expect colonizing populiations to possess genotypes favoring a high r, but genotypic variation in r depends on the heritabilities of life table statistics, and such measurements are yet to be made (10, 53). The fact that flight duration can be increased by appropriate selection in Oncopeltus fasciatus, and the demonstration of additive genetic variance for this trait in Lygaeus kalmii, suggest that heritability studies of migratory behavior would also be worth pursuing. Most interesting of course, will be possible genetic correlations between migration and life history parameters. Also, migration often transports genotypes across long distances with considerable mixing of populations. An understanding of its operation therefore carries with it implications for population genetics, zoogeography, and evolutionary theory. Finally, at least parts of the above general theory would seem to be applicable to forms other than insects. Bird and insect migrations, for example, are in many respects ecologically and physiologically similar. Birds, like insects, emphasize locomotory. as opposed to vegetative functions during long-distance flight; the well-known Zugenruhe or migratory restlessness is a case in point. Further, many birds migrateat nigt at a time when they would ordinarily roost(vegetative activity). Because their life spans exceed single seasons, bird migrants are not prereproductive in the same sense that insect migrants are, and hence reproductive values do not have the same meaning(but note that some insects are also interreproductive migrants). The situaion is complicated further by the fact that in many birds adult survivorship is virtually independent of age so that colonizing ability tends to be also (10, 54). Nevertheless, birds arrive on their nesting grounds in reproductive condition with the result that migration is a colonizing episode. It is also phenotypically modifiable by environmental factors, some of which, for example, photoperiod, influence insects as well (55). The similarities between birds and insects thus seem sufficient to indicate, at least provisionally, that the theory developed for insects applies also to birds with appropriate modifications for longer life span and more complex social behavior; comparisons between insects and fish (56) lead to the same conclusion. In birds especially, and also in other forms, various functions accessory to migration such as reproductive endocrinology, energy budgets, and orientation mechanisms have been studied extensively (55, 56). But there is need in vertebrates for more data andtheoy on the ecology and physiology of migratory behavior per se in order tobetter understand its evolution and its role in ecosystem function (5, 57). Migration in any animal cannot be understood until viewed in its entirety as a physiological, behavioral, and ecological syndrome.