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1.
New Forests - Adventitious rooting (AR) is an obligatory step for vegetative propagation of commercial woody species. Paper industries have interest in Eucalyptus globulus Labill and its hybrids...  相似文献   
2.
A new cytotoxic thiodepsipeptide, verrucosamide (1), was isolated along with the known, related cyclic peptide thiocoraline, from the extract of a marine-derived actinomycete, a Verrucosispora sp., our strain CNX-026. The new peptide, which is composed of two rare seven-membered 1,4-thiazepane rings, was elucidated by a combination of spectral methods and the absolute configuration was determined by a single X-ray diffraction study. Verrucosamide (1) showed moderate cytotoxicity and selectivity in the NCI 60 cell line bioassay. The most susceptible cell lines were MDA-MB-468 breast carcinoma with an LD50 of 1.26 µM, and COLO 205 colon adenocarcinoma with an LD50 of 1.4 µM. Also isolated along with verrucosamide were three small 3-hydroxy(alkoxy)-quinaldic acid derivatives that appear to be products of the same biosynthetic pathway.  相似文献   
3.
Abstract.— The freshwater mussel Elliptio complanata was provided water containing green algae and cyanobacteria delivered from the Partitioned Aquaculture System (PAS) at eight flow rates to determine algal filtration rates as mg of particulate organic carbon (POC)/kg wet tissue weight per h. The dominant taxon in cyanobacterial waters was Microcystis while the dominant taxa in green algal waters were Scenedesmus and Ankistrodesmus . The cell counts of Scenedesmus and Ankistrodesmus were the only algal taxa that were significantly different between the incoming water and water filtered by mussels. Filtration rates of POC obtained from green algal water were significantly greater than from cyanobacteria-dominated waters at all flow rates. A significant increase in mean filtration rate was observed as flow rates increased. The filtration rate of green algae increased as POC concentration increased, peaking at 28 mg C/L. A maximum filtration rate was not observed with cyanobacterial waters.  相似文献   
4.
Polycythaemia vera was diagnosed in a three-year-old domestic shorthaired cat referred because of seizures and a high packed cell volume (PCV). Laboratory examination revealed severe erythrocytosis (PCV 79 per cent). Diagnosis was reached by excluding causes for relative and secondary absolute polycythaemia. As phlebotomy proved impossible for initial treatment due to hyperviscosity, four leeches were used to suck blood and the PCV was consequently reduced to 64 per cent. A further 24 hours later, when bleeding at the sites of sucking had stopped, the PCV was 56 per cent. Long-term management of the condition was achieved with hydroxyurea (100 mg/cat once daily) and intermittent phlebotomy. Initial treatment using leeches in cases of polycythaemia vera is a simple, non-invasive, well tolerated and effective method where phlebotomy is not possible.  相似文献   
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6.
A mechanistic model called PLASMO was developed earlier to simulate grapevine downy mildew (Plasmopara viticola) and has been applied in several viticultural areas of Italy since 1988 by the collaboration of several research institutions of Firenze. In this study, a new simulation model based on fuzzy logic has been developed for the same structure (biological cycle of P. viticola). This approach allows classical quantitative information to be used together with qualitative information. Vague concepts can also be handled. Agrometeorological data is used, with an hourly time step, starting from budbreak to the end of the growing season. Air temperature, relative humidity, rainfall and leaf wetness are required. The simulated processes are the growth of grapevine leaf area and the main phases of the biological cycle of the pathogen: incubation, sporulation, germination, spore survival and inoculation. The main epidemiological outputs are timing of infection events and disease intensity. The performance of the model is evaluated and the mechanistic and fuzzy logic approaches are compared.  相似文献   
7.
Computed tomographic (CT) venography of the cervical vertebral canal was performed in six, clinically normal, adult mixed-breed dogs from 14 to 23 kg. After dogs were euthanized and saline perfused, a gelatin and iothalamate mixture was injected into the right external jugular vein. Contiguous, 4-mm-thick CT images were obtained with dogs in sternal recumbency. Dogs were kept in the same position as for the CT scan and frozen to approximately -8 degrees C. All post-contrast CT images were analyzed using similar bone window and level settings. Additional multiplanar reformatted dorsal images were obtained in all dogs. The frozen cadavers were sectioned through the cervical region extending from the occiput to T1 at approximately 8-mm intervals. The frozen sections were then compared with the CT images. The CT appearance of the normal cervical vertebral venous system was described and illustrated. Components such as the internal vertebral venous plexus, interarcuate veins, intervertebral veins, and vertebral veins were clearly identified on the CT images.  相似文献   
8.
The isolation and identification of Yersinia enterocolitica from minced meat on CIN agar medium is still one of the major problems in food microbiology because of the low selectivity of cefsulodin–irgasan–novobiocin (CIN) agar. A total of 198 minced meat samples were collected from commercial establishments (butcher shops and supermarkets) in seven German cities in order to investigate the sensitivity and specificity of three identification techniques suitable for the differentiation of Y. enterocolitica within the rich background flora on CIN agar plates. As expected isolation of Y. enterocolitica from minced meat on CIN agar medium after 72 h enrichment in peptone, sorbitol and bile salts (PSB) broth was difficult because all plates were abundantly covered with numerous ‘typical’Yersinia‐like colonies of bull's eye appearance as well as with atypical colonies. Based on the phenotype of the colonies it was possible to detect colonies showing Yersinia‐like growth on CIN agar in 52 samples (26%). For identification of Y. enterocolitica the API 20E system (bioMerieux, Nürtingen, Germany), the Yersinia identification kit (Merlin, Bornheim‐Hersel, Germany) and a 16S rRNA based PCR assay were compared. Only in one sample (0.5%) a Y. enterocolitica strain was detected by all methods. Of the three identification systems tested for routine laboratory diagnostics the API 20E system was found to be the most suitable tool to identify Y. enterocolitica colonies within the rich background flora from minced meat samples on CIN agar plates.  相似文献   
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10.

BACKGROUND

Sublethal effects of insecticides may negatively affect several biological and behavioral traits of insects. The lethal effects of pirimiphos-methyl and chlorfenapyr have been previously showed on Trogoderma granarium, but little knowledge is available about their sublethal effects at low concentrations on both sexes. Herein, the sublethal effects of pirimiphos-methyl and chlorfenapyr on the mobility of T. granarium males and females were investigated.

RESULTS

Lethal concentration (LC) values of pirimiphos-methyl and chlorfenapyr were lower for T. granarium females than males. LC values on males were LC10 = 0.000788 and 0.00139 mg active ingredient (a.i.) cm−2, LC30 = 0.00350 and 0.00535 mg a.i. cm−2, and LC50 = 0.00986 and 0.0136 mg a.i. cm−2 for pirimiphos-methyl and chlorfenapyr respectively. LC on females were LC10 = 0.000704 and 0.00110 mg a.i. cm−2, LC30 = 0.00323 and 0.00428 mg a.i. cm−2, and LC50 = 0.00925 and 0.0110 mg a.i. cm−2 for pirimiphos-methyl and chlorfenapyr respectively. The walking duration of beetles exposed to LC30 of pirimiphos-methyl was significantly lower than the individuals exposed to LC10 and LC30 of both insecticides and control ones. Pirimiphos-methyl LC30-exposed males remained more time on their back (101.7 s) than females (46.9 s), while the latter stayed immobile longer than males (381.7 s versus 371.9 s). The highest speed was recorded for control beetles (14.17 mm s−1 females vs. 12.44 mm s−1 males), while the lowest speed was observed in pirimiphos-methyl LC30-treated males (8.36 mm s−1) and females (9.66 mm s−1).

CONCLUSIONS

Overall, males and females exposed to low concentrations of pirimiphos-methyl and chlorfenapyr showed reduced motility. This knowledge can be exploited further to unlock behavioral effects of insecticides for effective pest management programs in warehouses. © 2023 Society of Chemical Industry.  相似文献   
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