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81.
Two flight parameters (take-off and duration) and respiration level were measured, in two years in summer and early autumn, in dormant Coccinella septempunctata L. (Coleoptera: Coccinellidae) collected while hidden in grass tussocks in hibernation sites (HID) and in beetles collected on plants (PLA). The duration of tethered flight of HID beetles measured in the laboratory in late August and September 1995 (range of geometric means 190–440 s) was slightly longer than the flight of PLA beetles (80–310 s), both being much longer than trivial flight recorded in beetles foraging for prey during the breeding season (35 s). In general, the flight performance had a tendency to increase in September and to decrease in October.The oxygen consumption in HID beetles increased throughout September 1994 from 430 to 780 l g–1 h–1 and throughout October 1995 from 710 to 1060 l g–1 h–1. This increase is ascribed to a concomitant decrease in diapause intensity. A similar increase was observed also in PLA beetles in 1994 and oxygen consumption was always higher than in HID beetles, most probably due to feeding and digestion in PLA beetles.Laboratory feeding of HID beetles on aphids induced maturation of ovaries and increased oxygen uptake (from 680 to 1110 l g–1 h–1). Feeding on honey and pollen left their oxygen uptake unchanged. Effect of feeding on the flight parameters was mostly not significant. In agreement with its less suitable body shape and usually less distant dormancy sites, C. septempunctata was found a less apt flier than long-distance migrating coccinellid species.  相似文献   
82.
Riassunto Il nostro lavoro di molti anni sulle cascade travertinose dei fiumi carstici jugoslavi era diretto verso le esplorazioni delle condizioni di vita su questi specifici biotopi. A causa di questa specificità loro erano potuti popolati solo da determinati specie di piante e di animali, i queli sono adattati su queste condizioni speciali. Esse creano le associazioni, ai queli fa la base la vigorosa vegetazione di muschi e di alghe, e un po'di meno anche di altri piante. Questa vegetazione e accompagnata da numerosi rappresentanti dai diversi gruppi di animali, come queli di Turbellaria, Gastropoda, Oligochaeta, Hirudinea, Amphipoda, Insecta ed a.Dai fattori ecologici erano esplorati le condizioni di vita fisicochimiche e biologiche. In estate la temperatura dell'aqua era sempre oltre la temperatura-limite di deposizione (oltre 14° C), e durante l'inverno generalmente erano le condizioni inconvenienti per i processi di deposizione.Nella parte superficiale delle cascade abiamo constatato due specie di abitazione in relazione della luce. Forte illuminate cascade erano popolate dalle associazioni della luce, ed a causa di meno calcificata vegetazione erano molto più. ricche di animali. Meno illuminate cascade avevano più favorevoli condizioni per il sviluppo della vegetazione travertinosa, la quale era molto calcificata, the cosa non porgeva favorevoli condizioni per il sviluppo del mondo animale.Abiamo constatato the la più favorevole velocità dell'aqua per lo sviluppo dei organismi, i quali popolano i posti delle cascade travertinose, è tra 0,5 e l,5 m/sec., sebbene sui singoli abitazioni la velocita dell'aqua era fra 0,5–3,5 m/sec.A causa di una favorevole alcalità, la quale nelle aque esplorate ammonta tra 2,8 e 5,2, i processi di deposizione sono molto attivi. E costattato un graduale abassamento dell'alcalità in direzione scendente del flume, the cosa si mette in relazione colla perdita del carbonato durante il processo di deposizione.La quantità del ossigeno ammontava da 3,5–9 ccm/l. e perciò generalmente tutte queste aque si possono considerare come poliossitipiche.Per le biocenosi delle cascade travertinose e caratteristica una grande dinamica nel Toro sviluppo. Le più primitive forme delle associazioni sono composte principalmente dai idrofiti. Con un avanzato sviluppo delle formazioni travertinose appariscono nuove stazioni con nuove associazioni. Il climax presenta la vegetazione fanerogama, la quala crew stazioni ombreggiate, dove si sviluppa speciale vegetazione travertinosa dell' ombra. Questi cambiamenti di vegetazione vengono accompagnati da numerose specie di animali dei gruppi Amphipoda, Ephemerida, Trichoptera, Plecoptera, Coleoptera ed a.In fine sono dimostrate le principali caratteristiche di vita in relazione colle condizioni fisico-chimiche e biologiche.
Summary For a number of years, our work on travertine cascades of Yugoslav Karstic rivers has been directed towards the study of living conditions in these specific biotypes. Owing to their specificity, they could have been inhabited only by certain plant and animal species which have been adapted to these specific conditions. Their communities have been created on a rich moss and seaweed vegetation basis and, to a somewhat smaller extent, also on that of other plants. This vegetation is accompanied by numerous representatives of various animal groups such as: turbellaria, gastropods, oligochaeta, hirudinoids, amphipods, insects et al.As far as ecologic factors are concerned, physical, chemical and biological living conditions have been studied. In summer, water temperature is always above the deposition boundary (above 14°C), while in winter, conditions are generally unfavourable for deposition processes.In connection with light, two habitats were observed on the surface parts of the cascades. The strongly lighted cascades were inhabited by light communities which were considerably richer in animal population, owing to poorly calcified vegetation. As to the development of travertine vegetation, poorly lighted cascades which had been amply calcified, were in a much more favourable position and thus provided unfavourable conditions for the development of animal life.The water speed most favourable for the development of organisms inhabiting travertine cascades has been found to lie between 0.5 and 1.5 meters per second, although in individual habitats water speed amounted to between 0.5 and 3.5 meters per second.Owing to favourable alkalinity, amounting, in the waters investigated, to between 2.8 and 5.2, depositing processes have been very intense. The gradual lowering of alkalinity in the downstream course of rivers, which is brought into connection with the losing of carbonates during the deposition process, has also been established.As the quantity of oxygen amounted to between 3.5–9 ccm/l, these waters can be considered to be polyoxitypical.The biocenosis on travertine cascades are characterized by their very dynamic development. The most primitive forms of communities are mainly composed of hydrophytes. The further development of travertine forms brings about new habitats with new communities. The climax is represented by phanerogamic vegetation, creating rocky habitats where special travertine shade vegetation develops. These changes in vegetation have been accompanied by numerous animal species of the afore-mentioned groups.Finaly, the main characteristics of life in terms of physical, chemical and biological conditions have been presented.

Zusammenfassung Die mehrjärige Arbeit der Autoren auf den Kalktuffbildenden Wasserfällen der jugoslawischen Karstgewässer war den Erforschungen der Lebensbedingungen auf diesen spezifischen Biotopen gewidmet. Wegen ihrer Eigentümlichkeit konnten die Kalktuffwasserfälle nur von bestimmten Pflanzen- und Tierarten besiedelt werden, die an these besonderen Bedingungen angepasst sind. Sie bilden Gemeinschaften auf eine üppige Moos- und Algenvegetation und etwas weniger auch auf anderen Pflanzen. Diese Vegetation wird von zahlreichen Vertretern verschiedener Tiergruppen begleitet, wie Turbellaria, Gastropoda, Oligochaeta, Hirudinea, Amphipoda, Insecta u.a.Von ökologischen Faktoren wurden die physikalisch-chemischen und biologischen Bedingungen untersucht. Im Sommer war die Wassertemperatuur immer über der Grenztemperatur der Ablagerung (über 14°C), während die Ablagerungsbedingungen im Winter im allgemeinen ungünstig waren.In den oberflächenlichen Teilen der Wässer\:falle wurden, im Verhältnis zu dem Licht, zwei Arten von Standorten festgestellt. Die stark belichteten Wasserfälle sind von Lichtgerneinschaften besiedelt, die wegen der weniger kalzifizierten Vegetation viel mehr Tiere enthalten. Weniger belichtete Wasserfälle zeigen günstigere Bedingungen für eine Entwicklung der Kalktuffvegetation. Diese Vegetation wird sehr kalzifiziert und ist für der Entwicklung der Tierwelt ungünstig.Es wurde festgestellt, dass die günstige Wassergeschwindigkeit für die Entwicklung von Organismen, die die Standorte der Kalktuffwasserfälle besiedeln, zwischen 0,5 and 1,5 m-Sek ist, wiewohl die Wassergeschwindigkeit an einzelnen Standorten zwischen 0,5 and 3,5 m-Sek betrug.Wegen der günstigen Alkalität (2,8–5,2) sind die Ablagerungsvorgänge sehr aktiv. Flussabwärts wurde ein allmählicher Fall der Alkalitätwerte festgestellt, was auf den Verlust des Karbonates während der Ablagerungsvorgänge zurückgeführt wird.Die Sauerstoffmenge beträgt zwischen 3,5–9 ccm/l; im allgemeinen können wir deshalb all these Gewässer als polyoxytypisch betrachten.Für die Gemeinschaften der Kalktuffwasserfälle ist eine grosse Dynamik in ihrer Entwicklung charakteristisch. Die primitivsten Formen der Lebensgemeinschaften sind hauptsächlich aus Hydrophyten zusammengesetzt. Mit der weiteren Entwicklung der Kalktufformen erscheinen neue Standorte mit neuen Gemeinschaften. Das Klimax stellt die Vegetation der höheren Pflanzen tar, die Schattenstandorte macht, wo sich eine besondere Schattenkalktuf-vegetation entwickelt. Diese Vegetationsänderungen werden von zahlreichen Tierarten der genanten Gruppen begleitet.Zum Schluss wird die Hauptcharakteristik des Lebens in Bezug auf die physikalisch-chemischen und biologischen Bedingungen dargestellt.


Botaniki institut Univerziteta Zagreb

Bioloki institut Univerziteta Zagreb  相似文献   
83.
Cell-based delivery of therapeutic viruses has potential advantages over systemic viral administration, including attenuated neutralization and improved viral targeting. One of the exciting new areas of investigation is the potential ability of endothelial-lineage cells to deliver genes to the areas of neovascularization. In the present study, we compared two types of endothelial-lineage cells [outgrowth endothelial cells (OECs) and culture-modified mononuclear cells (CMMCs), also known as "endothelial progenitor cells"] for their ability to be infected with adenovirus and to home to the areas of neovascularization. Both cell types were isolated from peripheral blood of healthy human donors and expanded in culture. We demonstrate that OECs are more infectable and home better to tumors expressing VEGF on systemic administration. Furthermore, we used an adenoviral/retroviral chimeric system to convert OECs to retrovirus-producing cells. When injected systemically into tumor-bearing mice, OECs retain their ability to produce retrovirus and infect surrounding tumor cells. Our data demonstrate that OECs could be efficient carriers for viral delivery to areas of tumor neovascularization.  相似文献   
84.
Early weaning is a technique used to increase swine health status, and may cause consequences in reproductive performance of sows. An experiment was performed to evaluate these effects in a herd of sows, with weaning at 9 or 10 days post-farrowing, located in west of Minas Gerais, Brazil. Large-White sows (n=102), with three or four previous parturitions were randomly allocated to three treatment groups: T1: artificial insemination (AI) at first post-weaning estrus of the sows; T2: AI at second post-weaning estrus, T3: AI at first estrus, after an administration of a daily individual dose of 20 mg of altrenogest from 5 to 8 days post-weaning. The duration of the first post-weaning estrus did not differ among treatment groups; however, the second estrus of the T2 group was of shorter duration relative to the other treatment groups (P< or =0.035). Ovulation occurred earlier at the second estrus of the T2 group, compared with the T1 and T3 groups (P< or =0.027), being similar to that at the first estrus of T2 group (P=0.177). The relationship of the timing between ovulation and estrus was similar among treatment groups (P> or =0.221). There was no difference in farrowing rate among treatment groups (P> or =0.313). The T2 group produced a mean of 2.5 more piglets per litter (P=0.002). In conclusion, the use of altrenogest did not increase the reproductive performance of early-weaned sows.  相似文献   
85.
Alignment of RNA base pairing probability matrices   总被引:6,自引:0,他引:6  
MOTIVATION: Many classes of functional RNA molecules are characterized by highly conserved secondary structures but little detectable sequence similarity. Reliable multiple alignments can therefore be constructed only when the shared structural features are taken into account. Since multiple alignments are used as input for many subsequent methods of data analysis, structure-based alignments are an indispensable necessity in RNA bioinformatics. RESULTS: We present here a method to compute pairwise and progressive multiple alignments from the direct comparison of base pairing probability matrices. Instead of attempting to solve the folding and the alignment problem simultaneously as in the classical Sankoff's algorithm, we use McCaskill's approach to compute base pairing probability matrices which effectively incorporate the information on the energetics of each sequences. A novel, simplified variant of Sankoff's algorithms can then be employed to extract the maximum-weight common secondary structure and an associated alignment. AVAILABILITY: The programs pmcomp and pmmulti described in this contribution are implemented in Perl and can be downloaded together with the example datasets from http://www.tbi.univie.ac.at/RNA/PMcomp/. A web server is available at http://rna.tbi.univie.ac.at/cgi-bin/pmcgi.pl  相似文献   
86.
Casein, a protein found in milk of several species, is divided into different chains from 19 to 25 kDa. Casein is also considered as a source of amino acids and generating peptides with biological activities such as opiate, immunostimulating, antibacterial, peptidase inhibitors, among others. In this work, Sephadex G-10 chromatography followed by high-performance liquid chromatography isolation purified NZCase TT, an industrial culture media for tetanus toxin production. In the first step, four pools were isolated and tested in different assays: isolated smooth muscle assay (guinea pig ileum, rat uterus), phagocytosis in vitro of opsonized sheep red blood cells, and hydrogen peroxide (H2O2) release from mouse peritoneal macrophages. Pool III was the main active pool being able to potentiate bradykinin action in guinea pig ileum, stimulating phagocitic activity by resident macrophages and increasing H2O2 release from macrophages previously activated with bacille Calmette Guérin. Using mass spectra the primary structure of the main peptide from pool III was obtained--INKKI, which corresponds to beta-casein fragment 26-30. The immunostimulating action is probably related to a direct action in macrophage cells.  相似文献   
87.
Vienna RNA secondary structure server   总被引:1,自引:0,他引:1       下载免费PDF全文
The Vienna RNA secondary structure server provides a web interface to the most frequently used functions of the Vienna RNA software package for the analysis of RNA secondary structures. It currently offers prediction of secondary structure from a single sequence, prediction of the consensus secondary structure for a set of aligned sequences and the design of sequences that will fold into a predefined structure. All three services can be accessed via the Vienna RNA web server at http://rna.tbi.univie.ac.at/.  相似文献   
88.
The aim of this investigation was to determine the levels of heavy metals and metalloids in freshwater fish from the Zagreb area. A total of 216 freshwater fish samples from 5 sites were examined: Sava river upstream from Zagreb, Sava river at Zagreb, Sava river downstream from Zagreb, Jarun Lake, and 5 "ecologic" fishponds from the Zagreb surroundings. The metals lead, cadmium, mercury and the metalloid arsenic were determined by the method of atomic absorption spectrometry. The mean pooled levels of lead, cadmium and arsenic in all fish samples were 112.3 +/- 95 micrograms/kg, 8.5 +/- 11 micrograms/kg and 23.5 +/- 36 micrograms/kg, and did not exceed the allowed levels of 1,000 mg/kg, 100 micrograms/kg and 200 micrograms/kg, respectively. In 4 fish samples, the levels of mercury exceeded the allowed limit of 500 micrograms/kg (509, 596, 605 and 788 micrograms/kg), however, the pooled mean level of mercury was 127.8 +/- 90 micrograms/kg. There was no major difference in the levels of heavy metals between the two fish families observed, although the levels of lead, cadmium and mercury were higher in the family Ictaluridae (144 vs. 107 micrograms/kg, 10.4 vs. 8.2 micrograms/kg, and 153 vs. 124 micrograms/kg, respectively), whereas the level of arsenic was higher in the family Cyprinidae (23.8 vs. 21.8 micrograms/kg). Although the Sava river at Zagreb is the main recipient of sewage and wastewater in the Republic of Croatia, the levels of heavy metals were within the allowed limits in all groups of freshwater fish samples, with the exception of 4 samples that contained moderately elevated levels of mercury. Study results suggest that only mercury could be considered a good indicator of environmental pollution, because higher levels of mercury were measured in the fish from the Sava river than in the fish from the Jarun Lake and fishponds from the Zagreb surroundings, considering both pooleded and fish family specified data.  相似文献   
89.
Repetitive doses of the growth factor Fms-like tyrosine kinase receptor-3 ligand (Flt3L) have resulted in increased numbers of dendritic cells (DC) in various organs, and the effect on protective or tolerogeneic responses in the gut wall has been documented in the literature. In this study, for the first time, Flt3L was locally applied in the trachea of rats using a single dose only. A dose-dependent increase not only of DC, but also of T lymphocytes (CD4(+) and CD8(+)), was seen with a maximum on day 3. The effects on the cells in the lung interstitium and the bronchoalveolar space showed some differences. The use of tetanus toxoid as a model Ag applied intratracheally after the local Flt3L stimulation resulted in increased levels of specific IgA and IgG in the lung. Thus, this novel approach of locally stimulating APCs by topical application of a DC growth factor before applying the Ag offers a new vaccination strategy.  相似文献   
90.
Schistosomes and soil-transmitted helminths currently infect a third of the world's human population. An important feature of these parasitic infections is their focal distribution, which has significant implications for control. Only a few studies have been carried out at the microepidemiological scale, comparing infection levels among individuals or households within a single village. In this study, data are presented from a cross-sectional survey, examining all children attending a primary school in rural C?te d'Ivoire over several consecutive days for Schistosoma mansoni, soil-transmitted helminths, and intestinal protozoa. All houses in the main village were mapped, and school children were linked to these households for small-area spatial analyses. Comparison between the 260 school children who live within the main village and the 89 children who reside in nearby settlements revealed significant differences in the overall prevalence and intensity of infections with S. mansoni and hookworm, confirming the focal nature of these 2 parasites. On the other hand, S. mansoni and hookworm infections exhibited random spatial patterns within the main village. The validity of these results is discussed in the context of this epidemiological setting, drawing attention to the issue of scale. Our findings have direct implications for intervention because they call for a uniform, community-wide approach to control schistosomiasis and soil-transmitted helminthiasis. Implementation can be relatively straightforward, and the proposed control approach might be cost-effective and prove sustainable.  相似文献   
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