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1.
This study assesses the comparative sensitivity and possibility of obtaining fast results of various methods of biotesting for several surfactants: Tween 85, sodium dodecyl sulfate (SDS), Fairy dishwashing gel, and Mif washing powder. The following test organisms are used for the study: luminescent bacteria Photobacterium phosphoreum (Beijerinck), preparation of Ecolum luminescent bacteria, unicellular algae Scenedesmus quadricauda (G.M. Smith), infusorian Paramecium caudatum (Ehrenberg), and crustacean Daphnia magna (Straus). It has been revealed that Fairy dishwashing gel possesses the strongest toxicity against the studied test objects. Daphnia and algae are most sensitive to the effects of Fairy and SDS, protozoan and luminescent bacteria are most sensitive to SDS, and Ecolum is most sensitive to Mif washing powder. The tested aquatic organisms and Ecolum are most tolerant to the effect of Tween 85.  相似文献   

2.
A major use of small-sided games (SSGs) in soccer training is the concomitant development of game-specific aerobic fitness. We hypothesize that the SSG formats of 2 vs. 2, 3 vs. 3, and 4 vs. 4 players reveal game-like intensities and therefore are most adequate to increase game-specific aerobic fitness. Heart rate (HR), percentage of maximum heart rate (HRmax), blood lactate concentration (La), and time-motion characteristics of 17 elite male youth soccer players (aged 14.9 ± 0.7 years, V[Combining Dot Above]O2max 61.4 ± 4.5 ml·kg·min, HRmax 199.6 ± 7.3 b·min) were collected by global positioning systems while performing the SSG formats. Repeated-measures analysis of variance and effect sizes were calculated to demonstrate the differences between SSG formats. Highest physiological responses were obtained in 2 vs. 2 (HR: 186 ± 7 b·min, HRmax: 93.3 ± 4.2%, La: 5.5 ± 2.4 mmol·L) followed by 3 vs. 3 (HR: 184 ± 8 b·min, HRmax: 91.5 ± 3.3%, La: 4.3 ± 1.7 mmol·L) and 4 vs. 4 (HR: 179 ± 7 b·min, HRmax 89.7 ± 3.4%, La: 4.4 ± 1.9 mmol·L). Pronounced differences were found for most physiological parameters and for time spent in the speed zones "walking" (<5.3 km·h), "moderate-speed running" (10.3-13.9 km·h), and "maximum sprinting" (≥26.8 km·h). The findings suggest that all the formats reveal game-like intensities and are suitable for aerobic fitness improvements. However, we found pronounced demands on the anaerobic energy supply in 2 vs. 2, whereas 3 vs. 3 and 4 vs. 4 remain predominantly on an aerobic level and differ mainly in the HR response. We suggest using 3 vs. 3 for soccer-specific aerobic fitness training.  相似文献   

3.
A typification of Moscow city habitats is undertaken, based on their consideration as mosaic of patches and using such fundamental parameters as habitat origin (soil type), floristic composition, vegetation structure, and area of the biotopes. Altogether, 11 habitat types are distinguished: lawns, agrocenoses, xerophytic and mesophytic meadows, tall weeds, boulevards, small degenerative parks, small oppressed artificial parks, landscape parks, forest parks, and technocenoses. Such a classification is primarily useful for studying ants. The present paper describes the basic structure of ant assemblages in most types of urban biocenoses. The main pool of Moscow’s ant species ranked by their occurrence is as follows: Lasius niger (87%), Myrmica rugulosa (44%), Myrmica rubra (33%), Formica cunicularia (11%), Myrmica ruginodis (10%), etc. Leaf litter removal with a rake was shown to negatively affect the numbers, biomass, and species diversity of ant communities in urban areas with trees. The most stable two-species ant community revealed in Moscow City, termed an “elementary urban community,” consists of L. niger and M. rugulosa, with the former always outnumbering the latter.  相似文献   

4.
In Costa Rica, the Gulf of Nicoya shrimp fishery originated in 1952 and represented one of the most important economic activities in the region. Nevertheless, overfishery reduced the captured volumes to levels that prevent this commercial activity. I analyzed official fishery statistics between 1991 and 1999. These species involved are: two species of white shrimp, (Litopenaeus occidentalis and L. stylirostris), the "titi" shrimp (Xiphopenaeus riveti), the brown shrimp (Farfantepenaeus californiensis), the "pinki" shrimp (F. brevirostris) and the "fidel" shrimp (Solenocera agassizi). All the species reached the Maximum Sustainable Yield in the decades of 1970 and 1980 and are now found at over-exploitation levels. I recommend that this shrimp trawl fishery be completely closed down.  相似文献   

5.
The most representative sample of molecular data, especially 16S and 12S rDNAs, is used to study the phylogeny and evolution of 57 species of three tribes, Rhodniini, Linshcosteini, and Triatomini, of the subfamily Triatominae. For the first time both New World and Old World species are brought together in a single phylogenetic analysis. Maximum-parsimony and distance estimation place both the Asiatic representatives, Linshcosteus and Triatoma rubrofasciata, as sister groups. The Linshcosteus-T. rubrofasciata clade nests firmly within Triatomini, in most analyses branching as a basalmost lineage, thus supporting a monophyletic origin of Triatominae. A paraphyly of "Triatoma" with respect to Linshcosteus, Dipetalogaster, Eratyrus, and Panstrongylus and the paraphyly of "Rhodnius" with respect to Psammolestes is observed in most of the analyses. Reinterpretation of triatomine biogeography points to the origin of Triatominae in northern areas of South America, in Central America, or in the southern region of North America. A few taxonomic changes are proposed: (1) reinclusion of Linshcosteus in Triatomini, (2) inclusion of Psammolestes in Rhodnius, (3) elevation of the "T. flavida complex" to the full genus Nesotriatoma (including N. flavida, N. bruneri, and N. obscura), (4) inclusion of the "T. spinolai complex" in Mepraia (including M. spinolai, M. gajardoi, M. eratyrusiformis, and M. breyeri), and (5) inclusion of "T." dimidiata in Meccus (M. dimidiatus).  相似文献   

6.
The present study reports the analyses of both isoprenoid and aromatic cytokinins in the coconut palm by combined high performance liquid chromatography and group specific enzyme immunoassays (HPLC-ELISA). The results showed that the isoprenoid cytokinins were several fold more abundant than the aromatic cytokinins in each of the plant parts analysed: immature inflorescence, shoot apical meristem (SAM), spear leaf and embryo. Within the isoprenoid cytokinins, the most abundant ones by type were the zeatin- (Z-), the isopentenyladenine- (iP-) and the dihydrozeatin- (DHZ-) type in decreasing order for most plant parts studied, and individually, zeatin riboside (ZR) or zeatin riboside-5-monophosphate (ZR5P) depending on the part. In the case of the iP-type cytokinins, the results showed that its 9-glucoside was the most abundant one in most parts. The isoprenoid cytokinin profiles in coconut showed a predominant pattern of 9-conjugation as a major metabolism route for these cytokinins. Analyses also showed the occurrence of the aromatic cytokinin 6-benzylaminopurine (BAP) and its riboside (BAPR), 9-glucoside (BAP9G), and nucleotide (BAPR5P). Their presence in coconut palm was unequivocally identified after permethylation by gas chromatography-mass spectrometry. They were more concentrated in the embryo and in the immature inflorescence than in the other two parts studied, however their concentration in each part was several times lower than that of isoprenoid cytokinins. All four were detected in each of the parts studied. The most abundant ones were BAPR and BAP9G in immature inflorescence; and BAPR in all of the other parts. When all cytokinins analysed are considered, differences between the plant parts studied were found. The zygotic embryos showed the highest content, double that in immature inflorescence, and five times more that in spear leaf and SAM. These differences are even greater when individual cytokinins are compared.  相似文献   

7.
The lipid and fatty acid compositions of microalgae were investigated in sea-ice and water samples from six different habitats of the Weddell Sea (Antarctica). All sea-ice samples and ice-associated water contained high algal biomass dominated by centric and pennate diatoms. Cells partially filled with oil droplets and resting spores were found. In the cells from the ice platelet layer triacylglycerols formed the largest component of the lipids. The fatty acid composition of sea-ice microalgae was dominated by the 16:1(n-7), 16:0, 18:1(n-9) and 20:5 (n-3) fatty acids. Except 18:1, they are typical for diatom fatty acids. These fatty acids were most abundant in pieces of first year ice with a brown colouration (brown-ice) and in the water column directly below sea-ice (sub-ice water). The small amounts of non-diatom acids, as 22:6 (n-3) and 18:4 (n-3), clearly showed that the sea-ice communities were not purely composed of diatoms. The most striking difference, in comparison to the general fatty acid composition of diatoms, was the high proportion of the 18:1 fatty acid in all samples, which might be caused by detrital material or lipid accumulation within cells and resting spores. In general, no clear adaptation of the fatty acid composition to the Antarctic and sea-ice environment was found. The fatty acid composition of the particulate matter from the water column was totally different from all other samples dominated by the saturated fatty acids 16:0 and 18:0.  相似文献   

8.
Sequence-dependent bending of DNA and phasing of nucleosomes   总被引:5,自引:0,他引:5  
Conformational analysis has revealed anisotropic flexibility of the B-DNA double helix: it bends most easily into the grooves, being the most rigid when bent in a perpendicular direction. This result implies that DNA in a nucleosome is curved by means of relatively sharp bends ("mini-kinks") which are directed into the major and minor grooves alternatively and separated by 5-6 base pairs. The "mini-kink" model proved to be in keeping with the x-ray structure of the B-DNA dodecamer resolved later, which exhibits two "annealed kinks", also directed into the grooves. The anisotropy of B DNA is sequence-dependent: the pyrimidine-purine dimers (YR) favor bending into the minor groove, and the purine-pyrimidine dinucleotides (RY), into the minor one. The RR and YY dimers appear to be the most rigid dinucleotides. Thus, a DNA fragment consisting of the interchanging oligopurine and oligopyrimidine blocks 5-6 base pairs long should manifest a spectacular curvature in solution. Similarly, a nucleotide sequence containing the RY and YR dimers separated by a half-pitch of the double helix is the most suitable for wrapping around the nucleosomal core. Analysis of the numerous examples demonstrating the specific alignment of nucleosomes on DNA confirms this concept. So, the sequence-dependent "mechanical" properties of the double helix influence the spatial arrangement of DNA in chromatin.  相似文献   

9.
中国古本草书艾蒿类植物的初步考订   总被引:5,自引:1,他引:4  
林有润 《植物研究》1991,11(1):1-24
本文对中国古本草书记载的艾蒿类植物,如白蒿、艾、白艾、艾蒿、野艾蒿、苹、籟蒿、水蒿、萎蒿、柳叶蒿、(艹闾)蒿、艾叶、家艾、蕲艾、牛尾蒿、草蒿、青蒿、黄花蒿、香蒿、臭蒿、狃蒿、邪蒿、茵陈蒿)蓬高、野同蒿、紫香蒿、牡蒿、齐头蒿、水辣菜、奄闾子、庵(艹闾)、刘寄奴及金寄奴等作了初步考订,同时对一些名为"艾"或"蒿"但非菊科蒿属植物亦作一初步的考订。  相似文献   

10.
We present a molecular phylogeny of bullfinches (Pyrrhula Brisson, 1760) based on 2357bp DNA sequence information of mitochondrial genes (cyt-b, 16S rRNA) and nuclear introns (fib-7, GAPDH-11). The genus is clearly a monophyletic group. Within the limits of Pyrrhula, molecular methods support the subdivision of three main groups: (1) "Southeast-Asian bullfinches" (P. nipalensis and P. leucogenis), (2) "Himalayan bullfinches" (P. aurantiaca, P. erythaca, P. erythrocephala), and (3) "Eurasian bullfinches" (P. pyrrhula s.l.). Within the last group there are four different subgroups: (3a) P. (p.) murina, (3b) P. (p.) cineracea, (3c) P. (p.) griseiventris, and (3d) P. pyrrhula s.str. The centre of origin of the genus Pyrrhula was most probably Southeast Asia. Incomplete lineage sorting of both mitochondrial and nuclear genes is observed among two apparently good species (P. erythaca and P. erythrocephala) indicating a very recent speciation event within the Himalayan Mountain chain. According to our estimates, the Pyrrhula ancestors split from the Pinicola ancestors before the Pleistocene. Apart from the subsequent Pre-Pleistocene splits of the three ancestral main groups, most of the diversification of today's representatives probably took place during the past 600,000 years, possibly in interaction with Pleistocene refugia and successive colonization movements after the last glaciation. Thus our work confirms the traditional delimitation of the bullfinches towards the other members of the finch family Fringillidae and corroborates most of the classic intra-generic subdivisions.  相似文献   

11.
The Southern Espinha?o Range consists of large areas covered by quartzitic or metaliferous tropical altitudinal fields. The Espinha?o Range ecosystems are endangered by anthropic high impacts, particularly due to mining and urbanization. We conducted a one-year inventory of the bee flora and fauna at the quartzitic Ouro Branco Mountains and a two-year survey of the metaliferous Ouro Preto fields. The samples were collected twice a month, from 8:00 am to 5:00 pm. The bees (677) belonged to 91 species, five families. The family Apidae was the richest and most abundant, followed by the Halictidae and Megachilidae. The bees visited 46 flowering plant species; the most visited plants were the Asteraceae (n = 220), the Malpighiaceae (n = 95), the Melastomataceae (n = 94), the Fabaceae (n = 78), and the Solanaceae (n = 63). Diversity was higher in Ouro Branco (H = 1.47) than in Ouro Preto (H = 1.17). The low richness and abundance of bees in our research site when compared to other Brazilian "Cerrado" areas can be due to the high altitude, low temperature, and low availability of flowers we found. "Canga" and rupestrian areas house fauna and flora species that are rare and threatened by extinction. The southern Espinha?o areas can, therefore, be given the status of permanent biodiversity preservation area.  相似文献   

12.
The "thermostable" B. thuringiensis exotoxin is active on cell cultures of Mammals "in vitro", except on the KB strain from a human tumor. The primary cultures are the most sensitive: first, with monkey kidney cells, the growth is inhibited by 0.1 mg of toxin per ml; next, the young rabbit kidney cells react to 0.25 mg of toxin per ml. The established lines of cells come last: human diploid cells (Lyon 4) and heteroploid cells (BHK21C13), with the same active dose of 1 mg of toxin per ml. No protection is obtained by adding ATP to monkey kidney cells at the same time as the exotoxin.  相似文献   

13.
Introduction: The human respiratory system is highly prone to diseases and complications. Many lung diseases, including lung cancer (LC), tuberculosis (TB), and chronic obstructive pulmonary disease (COPD) have been among the most common causes of death worldwide. Cystic fibrosis (CF), the most common genetic disease in Caucasians, has adverse impacts on the lungs. Bronchial proteomics plays a significant role in understanding the underlying mechanisms and pathogenicity of lung diseases and provides insights for biomarker and therapeutic target discoveries.

Areas covered: We overview the recent achievements and discoveries in human bronchial proteomics by outlining how some of the different proteomic techniques/strategies are developed and applied in LC, TB, COPD, and CF. Also, the future roles of bronchial proteomics in predictive proteomics and precision medicine are discussed.

Expert commentary: Much progress has been made in bronchial proteomics. Owing to the advances in proteomics, we now have better ability to isolate proteins from desired cellular compartments, greater protein separation methods, more powerful protein detection technologies, and more sophisticated bioinformatic techniques. These all contributed to our further understanding of lung diseases and for biomarker and therapeutic target discoveries.  相似文献   


14.
Fishes are constantly exposed to various sources of noise in their underwater acoustic environment. Many of these sounds are from anthropogenic sources, especially engines of boats. Noise generated from a small boat with a 55 horsepower outboard motor was played back to fathead minnows, Pimephales promelas, for 2 h at 142 dB (re: 1 Pa), and auditory thresholds were measured using the auditory brainstem response (ABR) technique. The results demonstrate that boat engine noise significantly elevate a fish's auditory threshold at 1 kHz (7.8 dB), 1.5 kHz (13.5 dB), and 2.0 kHz (10.5 dB), the most sensitive hearing range of this species. Such a short duration of noise exposure leads to significant changes in hearing capability, and implies that man-made noise generated from boat engines can have far reaching environmental impacts on fishes.  相似文献   

15.
Congenital disorders of glycosylation (CDGs) are disorders of abnormal protein glycosylation that affect multiple organ systems. Because most CDGs have been described in only a few individuals, our understanding of the associated phenotypes and the mechanisms of individual survival are limited. In the process of studying two siblings, aged 6 and 11 years, with MOGS-CDG and biallelic MOGS (mannosyl-oligosaccharide glucosidase) mutations (GenBank: NM_006302.2; c.[65C>A; 329G>A] p.[Ala22Glu; Arg110His]; c.[370C>T] p.[Gln124]), we noted that their survival was much longer than the previous report of MOGS-CDG, in a child who died at 74 days of age. Upon mutation analysis, we detected multiple MOGS genotypes including wild-type alleles in their cultured fibroblast and peripheral blood DNA. Further analysis of DNA from cultured fibroblasts of six individuals with compound heterozygous mutations of PMM2 (PMM2-CDG), MPI (MPI-CDG), ALG3 (ALG3-CDG), ALG12 (ALG12-CDG), DPAGT1 (DPAGT1-CDG), and ALG1 (ALG1-CDG) also identified multiple genotypes including wild-type alleles for each. Droplet digital PCR showed a ratio of nearly 1:1 wild-type to mutant alleles for most, but not all, mutations. This suggests that mitotic recombination contributes to the survival and the variable expressivity of individuals with compound heterozygous CDGs. This also provides an explanation for prior observations of a reduced frequency of homozygous mutations and might contribute to increased levels of residual enzyme activity in cultured fibroblasts of individuals with MPI- and PMM2-CDGs.  相似文献   

16.
The number and prevalence of coral diseases/syndromes are increasing worldwide. Dark Spot Syndrome (DSS) afflicts numerous coral species and is widespread throughout the Caribbean, yet there are no known causal agents. In this study we aimed to characterise the microbial communities (bacteria and fungi) associated with DSS lesions affecting the coral Stephanocoenia intersepta using nonculture molecular techniques. Bacterial diversity of healthy tissues (H), those in advance of the lesion interface (apparently healthy AH), and three sizes of disease lesions (small, medium, and large) varied significantly (ANOSIM R  = 0.052 p<0.001), apart from the medium and large lesions, which were similar in their community profile. Four bacteria fitted into the pattern expected from potential pathogens; namely absent from H, increasing in abundance within AH, and dominant in the lesions themselves. These included ribotypes related to Corynebacterium (KC190237), Acinetobacter (KC190251), Parvularculaceae (KC19027), and Oscillatoria (KC190271). Furthermore, two Vibrio species, a genus including many proposed coral pathogens, dominated the disease lesion and were absent from H and AH tissues, making them candidates as potential pathogens for DSS. In contrast, other members of bacteria from the same genus, such as V. harveyii were present throughout all sample types, supporting previous studies where potential coral pathogens exist in healthy tissues. Fungal diversity varied significantly as well, however the main difference between diseased and healthy tissues was the dominance of one ribotype, closely related to the plant pathogen, Rhytisma acerinum, a known causal agent of tar spot on tree leaves. As the corals’ symbiotic algae have been shown to turn to a darker pigmented state in DSS (giving rise to the syndromes name), the two most likely pathogens are R. acerinum and the bacterium Oscillatoria, which has been identified as the causal agent of the colouration in Black Band Disease, another widespread coral disease.  相似文献   

17.
Three new species of leaf beetles are described: Oreomela dudkorum sp. n. (Terektinskii Ridge, Central Altai Mountains), O. tuvensis sp. n. (mountains of southeastern Republic of Tuva), and O. romantsovi sp. n. (Western Sayan Mountains). The representatives of this genus, and especially of the nominotypical subgenus, were found in Russia and in the territories mentioned for the first time. Thus, the distribution boundary of this genus is shifted 3–4° northwards. The representatives of Oreomela have most probably migrated from Tien Shan to the mountains of southern Siberia via the Mongolian Altai Mountains.  相似文献   

18.
The degree of genetic determination of 25 quantitative dermatoglyphic characteristics has been studied on family: twin material: 45 pairs of MZ and 75 single-sex DZ twins; and 53 single-sex "parent-child" pairs. Approximating formulae were used to estimate main components of phenotypic variance due to additive interaction of genetic factors, to non-linear effects (intralocus dominance) and to the effect of total-familiar and random environmental factors. All the finger dermatoglyphic characteristics studied had a high degree of genetic determination (G greater than 0,80), and for most of them the contribution into the large variance of intralocus dominance effects was comparable with that of additive gene interaction, included in the determination of these characters. There are some palm dermatoglyphic characteristics ("ad" distance "cd" comb counting, "bad", "adt" and "cda" angles), which degree of genetic determination is low (G less than 0,35). At least ten quantitative finger and palm dermatogliphic characteristics with a high degree of genetic determination can be used for special studies in frames of multidimentional genetical analysis, including determination of twin zygosity type. Earlier described "indices" (using twin data) of relative role of genetic and environment factors in the determination of populational variability of quantitative characters are considered. None of them is shown to be a reliable estimate of the coefficient of genetic character determination. The use of these indices in practical studies can result in wrong conclusions on the degree and the character of genetic determination of quantitative characters.  相似文献   

19.
20.
A total of 290 species and varieties of Bacillariophyta including 32 that were new for the flora of Karelia and 18 that were new for the flora of Russia, have been recorded in phytoplankton in nine rivers of the White Sea basin. The genera Aulacoseira, Pinnularia, Eunotia, and Navicula s. l. are the richest in taxonomy. The maximum species diversity was recorded in the Suma (73), Kolezhma (91), and Chirko-Kem (146) rivers. The following species are the most widespread in the rivers that were under study here: A. ambigua, A. subarctica, A. subborealis, {tiA. tenella}, Asterionella formosa, and Tabellaria flocculosa.  相似文献   

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